相关申请的交叉引用CROSS-REFERENCE TO RELATED APPLICATIONS
本申请要求享有于2023年12月27日提交的名称为“电化学装置、电池包以及用电设备”的中国专利申请202311828023.7的优先权，该申请的全部内容通过引用并入本文中。This application claims priority to Chinese patent application 202311828023.7, filed on December 27, 2023, entitled “Electrochemical device, battery pack, and electrical equipment,” the entire contents of which are incorporated herein by reference.
本申请涉及电池技术领域，并且更具体地，涉及一种电化学装置、电池包以及用电设备。The present application relates to the field of battery technology, and more specifically, to an electrochemical device, a battery pack, and an electrical device.
随着电化学装置(例如，锂离子电池)在各类电子产品中的广泛应用，用户对于电化学装置的性能也提出了越来越高的要求。如何提高电化学装置的放电性能，一直是业内的研究方向。With the widespread application of electrochemical devices (such as lithium-ion batteries) in various electronic products, users have put forward higher and higher requirements on the performance of electrochemical devices. How to improve the discharge performance of electrochemical devices has always been a research direction in the industry.
本申请提供了一种电化学装置、电池包以及用电设备，其能提高放电性能。The present application provides an electrochemical device, a battery pack and an electrical equipment, which can improve discharge performance.
第一方面，本申请实施例提供了一种电化学装置，其包括壳体和容纳于壳体内的电极组件。电极组件包括第一极片、第二极片以及隔膜，第一极片、隔膜以及第二极片层叠并沿卷绕方向卷绕，第一极片和第二极片中的一者为正极极片，另一者为负极极片。第一极片包括第一集流体和设置于第一集流体上的第一活性物质，第一集流体包括第一主体区和第一空箔区，第一活性物质设于第一主体区，第一主体区和第一空箔区的布置方向垂直于卷绕方向。第一空箔区包括第一揉平区，第一揉平区远离第一主体区。In a first aspect, an embodiment of the present application provides an electrochemical device, which includes a housing and an electrode assembly contained in the housing. The electrode assembly includes a first pole piece, a second pole piece, and a diaphragm, the first pole piece, the diaphragm, and the second pole piece are stacked and wound along a winding direction, one of the first pole piece and the second pole piece is a positive pole piece, and the other is a negative pole piece. The first pole piece includes a first current collector and a first active material disposed on the first current collector, the first current collector includes a first main body area and a first empty foil area, the first active material is disposed in the first main body area, and the arrangement direction of the first main body area and the first empty foil area is perpendicular to the winding direction. The first empty foil area includes a first flattened area, and the first flattened area is away from the first main body area.
电化学装置被配置为：The electrochemical device is configured as follows:
响应于100％ SOC的电化学装置在第一环境温度下，以第一放电倍率执行放电操作，持续放电操作至电化学装置的SOC为0％，电化学装置的放电容量与电化学装置的额定容量之比大于或等于90％；In response to the electrochemical device having a 100% SOC, performing a discharge operation at a first discharge rate at a first ambient temperature, continuing the discharge operation until the SOC of the electrochemical device is 0%, and a ratio of the discharge capacity of the electrochemical device to the rated capacity of the electrochemical device is greater than or equal to 90%;
其中，第一环境温度为22℃-28℃，第一放电倍率在15C-20C的范围内。The first ambient temperature is 22°C-28°C, and the first discharge rate is in the range of 15C-20C.
电化学装置通过设置第一揉平区，可以增大过流能力，电化学装置电阻较小，在以15C-20C的高倍率进行放电时，电化学装置温升较低，有利于降低能量损耗，从而使电化学装置能够具有较高的放电容量，为用电设备提供更多的电能，改善电化学装置的放电性能。By setting the first flattening zone, the electrochemical device can increase the current capacity, the electrochemical device has a small resistance, and when discharged at a high rate of 15C-20C, the temperature rise of the electrochemical device is low, which is beneficial to reducing energy loss, so that the electrochemical device can have a higher discharge capacity, provide more electrical energy for electrical equipment, and improve the discharge performance of the electrochemical device.
在以上一个或多个可选的实施方式中，电化学装置的放电容量与电化学装置的额定容量之比大于或等于95％。电化学装置能够在以15C-20C的高倍率进行放电时，具有更高的放电容量，为用电设备提供更多的电能。In one or more optional embodiments above, the ratio of the discharge capacity of the electrochemical device to the rated capacity of the electrochemical device is greater than or equal to 95%. The electrochemical device can have a higher discharge capacity when discharged at a high rate of 15C-20C, providing more electrical energy for electrical equipment.
在以上一个或多个可选的实施方式中，电化学装置的放电容量与电化学装置的额定容量之比大于或等于98％。电化学装置能够在以15C-20C的高倍率进行放电时，具有更高的放电容量，为用电设备提供更多的电能。In one or more optional embodiments above, the ratio of the discharge capacity of the electrochemical device to the rated capacity of the electrochemical device is greater than or equal to 98%. The electrochemical device can have a higher discharge capacity when discharged at a high rate of 15C-20C, providing more electrical energy for electrical equipment.
在以上一个或多个可选的实施方式中，第一放电倍率在17.5C-20C的范围内。在以17.5C-20C的高倍率进行放电时，电化学装置的放电容量与电化学装置的额定容量之比大于或等于99％，可以为用电设备提供更多的电能。In one or more optional embodiments above, the first discharge rate is in the range of 17.5C-20C. When discharging at a high rate of 17.5C-20C, the ratio of the discharge capacity of the electrochemical device to the rated capacity of the electrochemical device is greater than or equal to 99%, which can provide more electrical energy for electrical equipment.
在以上一个或多个可选的实施方式中，第一环境温度为25℃。In one or more of the above optional embodiments, the first ambient temperature is 25°C.
在以上一个或多个可选的实施方式中，沿第一极片展开后的宽度方向，第一空箔区的尺寸为W1，第一集流体的总尺寸为W2，W1和W2满足：0.05≤W1/W2≤0.1。In one or more optional embodiments above, along the width direction of the unfolded first pole piece, the size of the first empty foil area is W1, the total size of the first current collector is W2, and W1 and W2 satisfy: 0.05≤W1/W2≤0.1.
将W1/W2限定为大于或等于0.05，可以使第一空箔区具有较大的宽度，便于实现第一空箔区与其它导电结构的连接，并在揉平时减小第一活性物质的受力，降低第一活性物质变形、掉粉的风险。将W1/W2限定为小于或等于0.1，可以为第一活性物质预留更多的空间，减少能量密度的损失。By limiting W1/W2 to be greater than or equal to 0.05, the first empty foil area can have a larger width, which is convenient for connecting the first empty foil area with other conductive structures, and reduces the force on the first active material during flattening, thereby reducing the risk of deformation and powder loss of the first active material. By limiting W1/W2 to be less than or equal to 0.1, more space can be reserved for the first active material, reducing the loss of energy density.
在以上一个或多个可选的实施方式中，沿第一极片展开后的宽度方向，第一揉平区的尺寸为W4，0.6≤W4/W1≤0.95。In one or more optional embodiments above, along the width direction of the unfolded first pole piece, the size of the first flattened area is W4, and 0.6≤W4/W1≤0.95.
将W4/W1限定为大于或等于0.6，可以增大第一空箔区在揉平过程中的受压区域，减小电极组件的轴向尺寸，提高空间利用率并使第一揉平区更为致密。将W4/W1限定为小于或等于0.95，可以在揉平过程中，减小传导至第一活性物质的力，降低第一活性物质脱落的风险。By limiting W4/W1 to be greater than or equal to 0.6, the pressure area of the first empty foil area during the flattening process can be increased, the axial size of the electrode assembly can be reduced, the space utilization rate can be improved, and the first flattened area can be made denser. By limiting W4/W1 to be less than or equal to 0.95, the force transmitted to the first active material can be reduced during the flattening process, reducing the risk of the first active material falling off.
在以上一个或多个可选的实施方式中，第一空箔区沿卷绕方向的外端的角部设有第一切口；沿第一极片展开后的长度方向，第一切口的尺寸为La。La和W1满足：0.2≤La/W1≤4。In one or more optional embodiments above, a first cutout is provided at the corner of the outer end of the first empty foil area along the winding direction; along the length direction of the first pole piece after unfolding, the size of the first cutout is La. La and W1 satisfy: 0.2≤La/W1≤4.
将La/W1限定为大于或等于0.2，可以在揉平过程中减少空箔材料的堆积，降低包覆第一空箔区的绝缘件被刺破的风险，提高安全性。将La/W1限定为小于或等于4，可以降低第一切口对第一空箔区的过流能力的影响。Limiting La/W1 to be greater than or equal to 0.2 can reduce the accumulation of empty foil material during the flattening process, reduce the risk of puncturing the insulating member covering the first empty foil area, and improve safety. Limiting La/W1 to be less than or equal to 4 can reduce the impact of the first incision on the current carrying capacity of the first empty foil area.
在以上一个或多个可选的实施方式中，沿第一极片展开后的宽度方向，第一切口的尺寸为W3；W3和W1满足：0.2≤W3/W1≤1。In one or more optional embodiments above, along the width direction of the unfolded first pole piece, the size of the first incision is W3; W3 and W1 satisfy: 0.2≤W3/W1≤1.
将W3/W1限定为大于或等于0.2，可以在揉平过程中减少空箔材料的堆积，降低包覆第一空箔区的绝缘件被刺破的风险，提高安全性。将W3/W1限定为小于或等于1，可以降低第一切口开设到第一主体区的风险，减少第一活性物质的损失。By limiting W3/W1 to be greater than or equal to 0.2, the accumulation of the empty foil material can be reduced during the flattening process, the risk of the insulating member covering the first empty foil area being punctured can be reduced, and safety can be improved. By limiting W3/W1 to be less than or equal to 1, the risk of the first incision being opened into the first main body area can be reduced, and the loss of the first active material can be reduced.
在以上一个或多个可选的实施方式中，沿第一极片展开后的长度方向，第一空箔区的尺寸为L1，第一主体区的尺寸为L2，L1和L2满足：0.8≤L1/L2≤1。In one or more optional embodiments above, along the length direction of the unfolded first pole piece, the size of the first empty foil area is L1, the size of the first main body area is L2, and L1 and L2 satisfy: 0.8≤L1/L2≤1.
第一空箔区具有较大的过流面积，在电化学装置以高倍率放电时，第一空箔区可以通过较大的电流，从而减小第一空箔区的产热、降低第一空箔区熔断的风险。The first empty foil area has a larger flow area. When the electrochemical device is discharged at a high rate, a larger current can pass through the first empty foil area, thereby reducing the heat generated by the first empty foil area and reducing the risk of the first empty foil area fusing.
在以上一个或多个可选的实施方式中，电化学装置还包括绝缘件，绝缘件环绕在第一揉平区的外侧，绝缘件的环绕接口处设有重叠区域，重叠区域避开第一揉平区沿卷绕方向的外端。In one or more optional embodiments above, the electrochemical device further comprises an insulating member, which surrounds the outer side of the first flattened zone, and an overlapping area is provided at the surrounding interface of the insulating member, and the overlapping area avoids the outer end of the first flattened zone along the winding direction.
绝缘片可以将第一揉平区与壳体隔开，以降低短路风险。绝缘片还可以从外周收拢第一揉平区，降低第一揉平区散开的风险。第一揉平区沿卷绕方向的外端不与重叠区域交叠，缓解重叠后的厚度增加导致径向上的尺寸的增大而降低能量密度的问题。The insulating sheet can separate the first flattened area from the shell to reduce the risk of short circuit. The insulating sheet can also gather the first flattened area from the periphery to reduce the risk of the first flattened area spreading out. The outer end of the first flattened area along the winding direction does not overlap with the overlapping area, alleviating the problem of increased thickness after overlap leading to increased radial dimensions and reduced energy density.
在以上一个或多个可选的实施方式中，电化学装置还包括设置于壳体的第一电极端子以及连接第一揉平区和第一电极端子的集流盘，集流盘设有通孔。In one or more optional embodiments above, the electrochemical device further comprises a first electrode terminal disposed on the housing and a current collecting plate connecting the first flattened area and the first electrode terminal, wherein the current collecting plate is provided with a through hole.
第一揉平区具有致密的端面，将第一揉平区与集流盘连接，可以提高连接强度。在注液工序中，电解液可以穿过通孔并浸润电极组件，改善浸润性。在电化学装置因过热、过充电、短路或其它原因而失效时，电极组件会释放气体；通过开设通孔，可以为气体提供通道，从而快速将气体排出到电化学装置的外部，降低爆炸风险。The first flattened area has a dense end surface, and connecting the first flattened area to the collector plate can improve the connection strength. During the injection process, the electrolyte can pass through the through hole and infiltrate the electrode assembly to improve wettability. When the electrochemical device fails due to overheating, overcharging, short circuit or other reasons, the electrode assembly will release gas; by opening the through hole, a channel can be provided for the gas, so that the gas can be quickly discharged to the outside of the electrochemical device, reducing the risk of explosion.
在以上一个或多个可选的实施方式中，正极极片包括正极集流体和正极活性物质，正极活性物质设于正极集流体上，正极活性物质包括Li1+aNix1Coy1Mnz1O2或Li1+aNix2Coy2Alz2O2中的至少一种。x1和x2均大于或等于0.8，y1和y2均大于0，z2和z3均大于0，x1+y1+z1＝1，x2+y2+z2＝1，-0.05≤a≤0.2。In one or more optional embodiments above, the positive electrode plate includes a positive electrode current collector and a positive electrode active material, the positive electrode active material is disposed on the positive electrode current collector, and the positive electrode active material includes at least one of Li1+a Nix1 Coy1 Mnz1 O2 or Li1+a Nix2 Coy2 Alz2 O2. x1 and x2 are both greater than or equal to 0.8, y1 and y2 are both greater than 0, z2 and z3 are both greater than 0, x1+y1+z1=1, x2+y2+z2=1, and -0.05≤a≤0.2.
在以上一个或多个可选的实施方式中，x1和x2均大于或等于0.9。In one or more of the above optional embodiments, x1 and x2 are both greater than or equal to 0.9.
在以上一个或多个可选的实施方式中，负极极片包括负极集流体和负极活性物质，负极活性物质包括人造石墨和/或天然石墨。In one or more optional embodiments above, the negative electrode plate includes a negative electrode current collector and a negative electrode active material, and the negative electrode active material includes artificial graphite and/or natural graphite.
在以上一个或多个可选的实施方式中，电化学装置还包括容纳于壳体内的电解液。电解液包括六氟磷酸锂和氟代碳酸乙烯酯，基于电解液的质量，六氟磷酸锂的质量百分含量为12％-16％，氟代碳酸乙烯酯的质量百分含量为0.8％-1.5％。氟代碳酸乙烯酯作为电解液添加剂，有利于提升SEI膜的性能，形成紧密结构层但又不增加阻抗，能阻止电解液进一步分解，提高电化学装置的放电性能。In one or more optional embodiments above, the electrochemical device further comprises an electrolyte contained in the housing. The electrolyte comprises lithium hexafluorophosphate and fluoroethylene carbonate, and based on the mass of the electrolyte, the mass percentage of lithium hexafluorophosphate is 12%-16%, and the mass percentage of fluoroethylene carbonate is 0.8%-1.5%. Fluoroethylene carbonate, as an electrolyte additive, is conducive to improving the performance of the SEI film, forming a compact structure layer without increasing impedance, preventing the electrolyte from further decomposing, and improving the discharge performance of the electrochemical device.
在以上一个或多个可选的实施方式中，电化学装置包括圆柱电芯。圆柱电芯生产工艺成熟、产品良率较高、散热性能好。In one or more of the above optional embodiments, the electrochemical device includes a cylindrical battery cell. The cylindrical battery cell has a mature production process, a high product yield, and good heat dissipation performance.
在以上一个或多个可选的实施方式中，圆柱电芯的直径为17mm-22mm，圆柱电芯的高度为64mm-72mm。In one or more of the above optional embodiments, the diameter of the cylindrical battery cell is 17 mm-22 mm, and the height of the cylindrical battery cell is 64 mm-72 mm.
在以上一个或多个可选的实施方式中，圆柱电芯为18650型电芯或21700型电芯。In one or more of the above optional embodiments, the cylindrical battery cell is a 18650 battery cell or a 21700 battery cell.
在以上一个或多个可选的实施方式中，电化学装置的额定容量为2500毫安时-4500毫安时。In one or more of the above optional embodiments, the rated capacity of the electrochemical device is 2500 mAh-4500 mAh.
在以上一个或多个可选的实施方式中，在第一环境温度下，电化学装置的直流电阻小于或等于10毫欧。电化学装置具有较小的直流电阻，电化学装置在以高倍率放电过程中温升较低，有利于降低能量损耗，提升电化学装置的放电容量，改善电化学装置的放电性能。In one or more optional embodiments above, at the first ambient temperature, the DC resistance of the electrochemical device is less than or equal to 10 milliohms. The electrochemical device has a smaller DC resistance, and the electrochemical device has a lower temperature rise during high-rate discharge, which is beneficial to reducing energy loss, increasing the discharge capacity of the electrochemical device, and improving the discharge performance of the electrochemical device.
第二方面，本申请实施例还提供了一种电池包，其包括根据第一方面任一实施方式提供的电化学装置。In a second aspect, an embodiment of the present application further provides a battery pack, which includes an electrochemical device provided according to any embodiment of the first aspect.
在以上一个或多个可选的实施方式中，电池包包括一个电池模组或并联设置的多个电池模组，一个电池模组包括串联设置的多个电化学装置。In one or more of the above optional embodiments, the battery pack includes a battery module or a plurality of battery modules arranged in parallel, and a battery module includes a plurality of electrochemical devices arranged in series.
第三方面，本申请实施例还提供了一种用电设备，其包括根据第二方面任一实施方式提供的电池包。In a third aspect, an embodiment of the present application further provides an electrical device, comprising a battery pack provided according to any implementation of the second aspect.
为了更清楚地说明本申请实施例的技术方案，下面将对本申请实施例中所需要使用的附图作简单地介绍。In order to more clearly illustrate the technical solution of the embodiments of the present application, the drawings required for use in the embodiments of the present application are briefly introduced below.
图1为本申请一些实施例提供的电化学装置的结构示意图；FIG1 is a schematic diagram of the structure of an electrochemical device provided in some embodiments of the present application;
图2为图1所示的电化学装置的爆炸示意图；FIG2 is an exploded schematic diagram of the electrochemical device shown in FIG1 ;
图3为本申请一些实施例提供的电化学装置的电极组件的正视示意图；FIG3 is a front view schematic diagram of an electrode assembly of an electrochemical device provided in some embodiments of the present application;
图4为图3所示的电极组件的俯视示意图；FIG4 is a schematic top view of the electrode assembly shown in FIG3 ;
图5为图3沿A-A方向作出的剖视示意图；Fig. 5 is a schematic cross-sectional view taken along the A-A direction of Fig. 3;
图6为本申请一些实施例提供的电化学装置的第一极片在展开状态下的示意图；FIG6 is a schematic diagram of a first electrode sheet of an electrochemical device in an unfolded state provided by some embodiments of the present application;
图7为图6沿B-B方向作出的剖视示意图；Fig. 7 is a schematic cross-sectional view taken along the B-B direction of Fig. 6;
图8为本申请一些实施例提供的电芯的第一揉平区、集流盘以及绝缘件的局部剖视示意图；FIG8 is a partial cross-sectional schematic diagram of a first flattened area, a current collecting plate, and an insulating member of a battery cell provided in some embodiments of the present application;
图9为本申请一些实施例提供的电芯的第一揉平区和绝缘件的局部剖视示意图；FIG9 is a partial cross-sectional schematic diagram of a first flattened area and an insulating member of a battery cell provided in some embodiments of the present application;
图10为本申请另一些实施例提供的电化学装置的第一极片在展开状态下的示意图；FIG10 is a schematic diagram of a first electrode sheet of an electrochemical device in an unfolded state provided by other embodiments of the present application;
图11为图10在圆框处的放大示意图；FIG11 is an enlarged schematic diagram of FIG10 at the circle frame;
图12为本申请又一些实施例提供的电化学装置的第一极片在展开状态下的示意图；FIG12 is a schematic diagram of a first electrode sheet of an electrochemical device in an unfolded state provided by some other embodiments of the present application;
图13为本申请再一些实施例提供的电化学装置的第一极片在展开状态下的示意图；FIG13 is a schematic diagram of a first electrode sheet of an electrochemical device in an unfolded state provided in some other embodiments of the present application;
图14为本申请另一些实施例提供的电化学装置的第一极片在展开状态下的示意图；FIG14 is a schematic diagram of a first electrode sheet of an electrochemical device in an unfolded state provided by other embodiments of the present application;
图15为本申请再一些实施例提供的电化学装置的第一极片在展开状态下的示意图；FIG15 is a schematic diagram of a first electrode sheet of an electrochemical device in an unfolded state provided in some other embodiments of the present application;
图16为本申请又一些实施例提供的电化学装置的第一极片在展开状态下的示意图；FIG16 is a schematic diagram of a first electrode sheet of an electrochemical device in an unfolded state provided by some other embodiments of the present application;
图17为本申请另一些实施例提供的电化学装置的第一极片在展开状态下的示意图；FIG17 is a schematic diagram of a first electrode sheet of an electrochemical device in an unfolded state provided by other embodiments of the present application;
图18为本申请又一些实施例提供的电化学装置的第一极片在展开状态下的示意图；FIG18 is a schematic diagram of a first electrode sheet of an electrochemical device in an unfolded state provided by some other embodiments of the present application;
图19为本申请另一些实施例提供的电化学装置的第一极片在展开状态下的示意图；FIG19 is a schematic diagram of a first electrode sheet of an electrochemical device in an unfolded state provided by other embodiments of the present application;
图20为本申请一些实施例提供的电化学装置的第二极片在展开状态下的示意图；FIG20 is a schematic diagram of a second electrode sheet of an electrochemical device provided by some embodiments of the present application in an unfolded state;
图21为图20沿C-C方向作出的剖视示意图；Fig. 21 is a schematic cross-sectional view taken along the C-C direction of Fig. 20;
图22为本申请一些实施例提供的电池包的示意图；FIG22 is a schematic diagram of a battery pack provided in some embodiments of the present application;
图23为本申请一些实施例提供的用电设备的示意图；FIG23 is a schematic diagram of an electrical device provided in some embodiments of the present application;
图24为本申请一些实施例提供的电化学装置以不同倍率放电的放电性能示意图；FIG24 is a schematic diagram of discharge performance of an electrochemical device provided by some embodiments of the present application at different discharge rates;
图25为图24的局部示意图。FIG. 25 is a partial schematic diagram of FIG. 24 .
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为使本申请实施例的目的、技术方案和优点更加清楚，下面将结合本申请实施例中的附图，对本申请实施例中的技术方案进行清楚地描述，显然，所描述的实施例是本申请一部分实施例，而不是全部的实施例。In order to make the purpose, technical solutions and advantages of the embodiments of the present application clearer, the technical solutions in the embodiments of the present application will be clearly described below in conjunction with the drawings in the embodiments of the present application. Obviously, the described embodiments are only part of the embodiments of the present application, not all of the embodiments.
在本申请的描述中，需要说明的是，除非另有明确的规定和限定，术语“安装”、“连接”等应做广义理解，例如，可以是固定连接，也可以是可拆卸连接，或一体地连接；可以是直接相连，也可以通过中间媒介间接相连，可以是两个元件内部的连通。对于本领域的普通技术人员而言，可以根据具体情况理解上述术语在本申请中的具体含义。In the description of this application, it should be noted that, unless otherwise clearly specified and limited, the terms "installation", "connection", etc. should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a direct connection, or an indirect connection through an intermediate medium, or it can be the internal communication of two components. For ordinary technicians in this field, the specific meanings of the above terms in this application can be understood according to specific circumstances.
在本申请的实施例中，“平行”不仅包括绝对平行的情况，也包括了工程上常规认知的大致平行的情况；同时，“垂直”也不仅包括绝对垂直的情况，还包括工程上常规认知的大致垂直的情况。示例性地，两个方向的夹角为85°-90°，可认为两个方向垂直；两个方向的夹角为0°-5°，可认为两个方向平行。In the embodiments of the present application, "parallel" includes not only the absolutely parallel situation, but also the roughly parallel situation conventionally recognized in engineering; at the same time, "perpendicular" also includes not only the absolutely perpendicular situation, but also the roughly perpendicular situation conventionally recognized in engineering. For example, if the angle between two directions is 85°-90°, the two directions can be considered perpendicular; if the angle between two directions is 0°-5°, the two directions can be considered parallel.
参照图1至图9，本申请实施例提供了一种电化学装置1000。电化学装置1000可以为二次电芯，二次电芯是指在电芯放电后可通过充电的方式使活性材料激活而继续使用的电芯。1 to 9 , an embodiment of the present application provides an electrochemical device 1000. The electrochemical device 1000 may be a secondary battery cell, which refers to a battery cell that can be continuously used by activating active materials by charging after the battery cell is discharged.
在一些实施例中，电化学装置1000可以为圆柱形电芯、棱柱电芯或其它形状的电芯，棱柱电芯包括方壳电芯、刀片形电芯、多棱柱电芯，多棱柱电芯例如为六棱柱电芯等。In some embodiments, the electrochemical device 1000 may be a cylindrical battery cell, a prismatic battery cell, or a battery cell of other shapes. The prismatic battery cell includes a square shell battery cell, a blade-shaped battery cell, a polygonal battery cell, and the polygonal battery cell is, for example, a hexagonal battery cell.
在一些实施例中，电化学装置1000包括壳体2和容纳于壳体2内的电极组件1。In some embodiments, the electrochemical device 1000 includes a housing 2 and an electrode assembly 1 accommodated in the housing 2 .
电极组件1包括极性相反的第一极片11和第二极片12。第一极片11和第二极片12中的一者为正极极片，另一者为负极极片。The electrode assembly 1 comprises a first pole piece 11 and a second pole piece 12 with opposite polarities. One of the first pole piece 11 and the second pole piece 12 is a positive pole piece, and the other is a negative pole piece.
在电化学装置1000充放电过程中，活性离子(例如锂离子)在正极极片和负极极片之间往返嵌入和脱出。During the charge and discharge process of the electrochemical device 1000 , active ions (eg, lithium ions) are inserted and removed back and forth between the positive electrode sheet and the negative electrode sheet.
可选地，电极组件1还包括设置在第一极片11和第二极片12之间的隔膜13，隔膜13将第一极片11和第二极片12绝缘。隔膜13可以降低正负极片短路的风险，同时可以使活性离子通过。Optionally, the electrode assembly 1 further includes a diaphragm 13 disposed between the first electrode sheet 11 and the second electrode sheet 12, and the diaphragm 13 insulates the first electrode sheet 11 from the second electrode sheet 12. The diaphragm 13 can reduce the risk of short circuit between the positive and negative electrode sheets, while allowing active ions to pass through.
壳体2内可以容纳一个或多个电极组件1。One or more electrode assemblies 1 may be accommodated in the housing 2 .
在一些实施例中，电极组件1可以为卷绕结构、叠片结构或其它结构。In some embodiments, the electrode assembly 1 may be a winding structure, a stacked structure, or other structures.
在一些实施例中，电极组件1的形状可以为圆柱状，扁平状或多棱柱状等。In some embodiments, the shape of the electrode assembly 1 can be cylindrical, flat, or polygonal.
在一些实施例中，壳体2用于封装电极组件1及电解液等部件。壳体2可以为钢壳、铝壳、塑料壳(如聚丙烯)或复合金属壳(如铜铝复合壳体2)等。In some embodiments, the housing 2 is used to encapsulate the electrode assembly 1 and components such as electrolyte. The housing 2 can be a steel housing, an aluminum housing, a plastic housing (such as polypropylene), or a composite metal housing (such as a copper-aluminum composite housing 2).
在一些实施例中，电化学装置1000还包括盖板5，壳体2具有开口，盖板5用于盖合开口。壳体2与盖板5配合以形成电化学装置1000的内部空腔，形成的内部空腔可以用于容纳电极组件1、电解液以及其他部件。In some embodiments, the electrochemical device 1000 further includes a cover plate 5, the housing 2 has an opening, and the cover plate 5 is used to cover the opening. The housing 2 and the cover plate 5 cooperate to form an internal cavity of the electrochemical device 1000, and the formed internal cavity can be used to accommodate the electrode assembly 1, the electrolyte and other components.
壳体2可以是多种形状和多种尺寸的，例如长方体形或圆柱体形。壳体2的材质可以是多种，比如，壳体2的材质包括但不限于铜、铁、铝、不锈钢、铝合金等。The shell 2 can be in various shapes and sizes, such as a rectangular parallelepiped or a cylindrical shape. The shell 2 can be made of various materials, for example, the material of the shell 2 includes but is not limited to copper, iron, aluminum, stainless steel, aluminum alloy, etc.
盖板5可通过焊接、粘接、卡接或其它方式连接于壳体2。The cover plate 5 can be connected to the housing 2 by welding, bonding, clamping or other methods.
在一些实施例中，壳体2可为一侧开口的结构，盖板5设置为一个并盖合于壳体2。在另一些实施例中，盖板5设置为两个，两个盖板5分别盖合于壳体2的两个开口。In some embodiments, the housing 2 may be a structure with one side open, and the cover plate 5 is provided as one and covers the housing 2. In other embodiments, two cover plates 5 are provided, and the two cover plates 5 cover the two openings of the housing 2 respectively.
在一些实施例中，电化学装置1000还包括电极端子3，电极端子3设置于盖板5。In some embodiments, the electrochemical device 1000 further includes an electrode terminal 3 , which is disposed on the cover plate 5 .
在一些示例中，电化学装置1000包括一个电极端子3，电极端子3和壳体2中的一者电连接于第一极片11，另一者电连接于第二极片12。电极端子3和壳体2中的一者作为电化学装置1000的正极，另一者作为电化学装置1000的负极。In some examples, the electrochemical device 1000 includes an electrode terminal 3, one of the electrode terminal 3 and the housing 2 is electrically connected to the first electrode sheet 11, and the other is electrically connected to the second electrode sheet 12. One of the electrode terminal 3 and the housing 2 serves as the positive electrode of the electrochemical device 1000, and the other serves as the negative electrode of the electrochemical device 1000.
在另一些示例中，电化学装置1000包括两个电极端子3，两个电极端子3分别电连接于第一极片11和第二极片12。两个电极端子3分别为电化学装置1000的正极和负极。In some other examples, the electrochemical device 1000 includes two electrode terminals 3, which are electrically connected to the first electrode sheet 11 and the second electrode sheet 12. The two electrode terminals 3 are the positive electrode and the negative electrode of the electrochemical device 1000, respectively.
在一些实施例中，电化学装置1000还包括集流盘4，集流盘4连接电极端子3和电极组件1。示例性地，集流盘4连接电极端子3和第一极片11。In some embodiments, the electrochemical device 1000 further includes a current collecting plate 4, which connects the electrode terminal 3 and the electrode assembly 1. Exemplarily, the current collecting plate 4 connects the electrode terminal 3 and the first electrode sheet 11.
在一些实施例中，第一极片11、隔膜13以及第二极片12层叠并沿卷绕方向V卷绕。卷绕方向V可为第二极片12、隔膜13以及第一极片11从内向外卷绕的方向。示例性地，如图5所示，卷绕方向V为顺时针方向。In some embodiments, the first pole piece 11, the diaphragm 13 and the second pole piece 12 are stacked and wound along a winding direction V. The winding direction V may be a direction in which the second pole piece 12, the diaphragm 13 and the first pole piece 11 are wound from inside to outside. For example, as shown in FIG5 , the winding direction V is clockwise.
在一些实施例中，第一极片11包括第一集流体111和设置于第一集流体111上的第一活性物质112。In some embodiments, the first electrode sheet 11 includes a first current collector 111 and a first active material 112 disposed on the first current collector 111 .
示例性地，第一集流体111可具有在其自身厚度方向相对的两个表面，第一活性物质112可设置在第一集流体111相对的两个表面的任意一者或两者上。For example, the first current collector 111 may have two surfaces opposite to each other in its thickness direction, and the first active material 112 may be disposed on any one or both of the two opposite surfaces of the first current collector 111 .
在一些实施例中，第一集流体111可采用金属箔片，例如不锈钢箔、铜箔、铝箔、镍箔等。In some embodiments, the first current collector 111 may be made of metal foil, such as stainless steel foil, copper foil, aluminum foil, nickel foil, etc.
在一些实施例中，第一集流体111包括第一主体区111a和第一空箔区111b，第一活性物质112设于第一主体区111a，第一主体区111a和第一空箔区111b的布置方向垂直于卷绕方向V。In some embodiments, the first current collector 111 includes a first main body region 111a and a first empty foil region 111b, the first active material 112 is disposed in the first main body region 111a, and the arrangement direction of the first main body region 111a and the first empty foil region 111b is perpendicular to the winding direction V.
示例性地，第一主体区111a和第一空箔区111b的布置方向平行于电极组件1的卷绕轴向P。Exemplarily, the arrangement direction of the first main body region 111 a and the first empty foil region 111 b is parallel to the winding axial direction P of the electrode assembly 1 .
第一主体区111a的至少一个表面涂覆有第一活性物质112。第一空箔区111b的两个表面均未涂覆第一活性物质112。At least one surface of the first main body region 111a is coated with the first active material 112. Both surfaces of the first empty foil region 111b are not coated with the first active material 112.
第一空箔区111b的部分区域可以设有其它不包括活性材料的涂层，比如绝缘涂层。当然，第一空箔区111b的至少部分区域的两个表面均是裸露地、未被其它涂层覆盖的。第一空箔区111b的裸露区域可以作为电极组件1的第一极耳10a，第一极耳10a可以将电极组件1的电流导出。Part of the first empty foil area 111b may be provided with other coatings that do not include active materials, such as insulating coatings. Of course, both surfaces of at least part of the first empty foil area 111b are exposed and not covered by other coatings. The exposed area of the first empty foil area 111b can serve as the first pole tab 10a of the electrode assembly 1, and the first pole tab 10a can lead out the current of the electrode assembly 1.
示例性地，将第一极片11展开后，第一主体区111a和第一空箔区111b的布置方向平行于第一极片的宽度方向Y。Exemplarily, after the first pole piece 11 is unfolded, the arrangement direction of the first main body region 111 a and the first empty foil region 111 b is parallel to the width direction Y of the first pole piece.
在一些实施例中，第一空箔区111b包括第一揉平区111c，第一揉平区111c远离第一主体区111a。示例性地，如图6所示，第一空箔区111b的位于虚线上侧的部分用于形成第一揉平区111c。In some embodiments, the first empty foil region 111b includes a first crumpled region 111c, which is away from the first main region 111a. Exemplarily, as shown in Fig. 6, the portion of the first empty foil region 111b located above the dotted line is used to form the first crumpled region 111c.
在电极组件1卷绕完成后，第一空箔区111b卷绕并大体形成柱状结构，外部工装可沿着柱状结构的周向对第一空箔区111b施加外力，使第一空箔区111b发生弯折变形，从而使第一空箔区111b沿径向相邻的两层更紧凑，并形成第一揉平区111c。After the electrode assembly 1 is wound, the first empty foil area 111b is wound and roughly forms a columnar structure. The external tooling can apply external force to the first empty foil area 111b along the circumference of the columnar structure to bend and deform the first empty foil area 111b, thereby making the two radially adjacent layers of the first empty foil area 111b more compact and forming a first flattened area 111c.
第一揉平区111c形成致密的端面，从而便于与其它导电结构连接，比如，与集流盘4焊接。The first flattened area 111 c forms a dense end surface, so as to facilitate connection with other conductive structures, such as welding with the collecting plate 4 .
在一些实施例中，电化学装置1000被配置为：响应于100％ SOC的电化学装置1000在第一环境温度下，以第一放电倍率执行放电操作，持续放电操作至电化学装置1000的SOC为0％，电化学装置1000的放电容量与电化学装置1000的额定容量之比大于或等于80％。第一环境温度为22-28℃，第一放电倍率在15C-20C的范围内。In some embodiments, the electrochemical device 1000 is configured to: in response to the electrochemical device 1000 having a 100% SOC, perform a discharge operation at a first discharge rate at a first ambient temperature, continue the discharge operation until the SOC of the electrochemical device 1000 is 0%, and the ratio of the discharge capacity of the electrochemical device 1000 to the rated capacity of the electrochemical device 1000 is greater than or equal to 80%. The first ambient temperature is 22-28°C, and the first discharge rate is in the range of 15C-20C.
在本申请实施例中，SOC(State of charge)是指电化学装置的荷电状态。In the embodiments of the present application, SOC (State of charge) refers to the state of charge of an electrochemical device.
在本申请实施例中，电化学装置1000的充放电操作在允许的充放电循环次数内进行。允许的充放电循环次数在从制造商或销售商在这些产品的标签、包装、用户手册、说明书、广告、营销或其他支持文件上获得,以便用户使用。In the embodiment of the present application, the charge and discharge operation of the electrochemical device 1000 is performed within the allowed number of charge and discharge cycles. The allowed number of charge and discharge cycles is obtained from the manufacturer or seller on the label, packaging, user manual, instruction manual, advertisement, marketing or other supporting documents of these products for user use.
示例性地，电化学装置处于100％的SOC可是指：在25℃下，电化学装置以0.5C恒流放电至该电化学装置的放电截止电压，然后以0.5C恒流充电至该电化学装置的充电截止电压，然后以充电截止电压恒压充电至0.05C，此时该电化学装置处于100％的SOC。Exemplarily, an electrochemical device being at 100% SOC may mean that at 25°C, the electrochemical device is discharged at a constant current of 0.5C to a discharge cut-off voltage of the electrochemical device, then charged at a constant current of 0.5C to a charge cut-off voltage of the electrochemical device, and then charged at a constant voltage of 0.05C at a charge cut-off voltage, at which time the electrochemical device is at 100% SOC.
示例性地，电化学装置的充放电过程可以通过电池测试仪(Neware CT-4016-5V-100A)测试。Exemplarily, the charge and discharge process of the electrochemical device can be tested by a battery tester (Neware CT-4016-5V-100A).
示例性地，电化学装置的放电截止电压和充电截止电压可以从制造商或销售商在这些产品的标签、包装、用户手册、说明书、广告、营销或其他支持文件上获得,以便用户使用。广告电压可包括数字电压值，或其他词、短语、字母数字字符组合、图标或向用户指示该电化学装置如何工作的标志。Exemplarily, the discharge cut-off voltage and charge cut-off voltage of the electrochemical device can be obtained from the manufacturer or seller on the label, packaging, user manual, instruction manual, advertisement, marketing or other supporting documents of these products for user use. The advertising voltage may include a digital voltage value, or other words, phrases, alphanumeric character combinations, icons or signs that indicate to the user how the electrochemical device works.
示例性地，电化学装置可为18650电芯或21700电芯。18650电芯的放电截止电压可为2.5V，充电截止电压可为4.2V。21700电芯的放电截止电压可为2.5V，充电截止电压可为4.2V。Exemplarily, the electrochemical device may be a 18650 battery cell or a 21700 battery cell. The discharge cut-off voltage of the 18650 battery cell may be 2.5 V, and the charge cut-off voltage may be 4.2 V. The discharge cut-off voltage of the 21700 battery cell may be 2.5 V, and the charge cut-off voltage may be 4.2 V.
示例性地，对于循环初期的电化学装置，在其载荷达到电化学装置的额定容量时，也可以认为该电化学装置处于100％的SOC。For example, for an electrochemical device at an early stage of a cycle, when its load reaches the rated capacity of the electrochemical device, the electrochemical device can also be considered to be at a SOC of 100%.
示例性地，电化学装置的额定容量可以认为：处于100％的SOC的电化学装置，在25℃下以0.2C的倍率恒流放电至0％的SOC，放出的容量即为额定容量。Exemplarily, the rated capacity of an electrochemical device can be considered as follows: when an electrochemical device at 100% SOC is discharged at a constant current rate of 0.2C at 25°C to 0% SOC, the discharged capacity is the rated capacity.
示例性地，电化学装置处于0％的SOC是指：电化学装置以一定倍率恒流放电至该电化学装置的放电截止电压，此时该电化学装置处于0％的SOC。Exemplarily, the electrochemical device being at a SOC of 0% means that the electrochemical device is discharged at a constant current rate to a discharge cut-off voltage of the electrochemical device, at which time the electrochemical device is at a SOC of 0%.
示例性地，电化学装置的额定容量可以从制造商或销售商在这些产品的标签、包装、用户手册、说明书、广告、营销或其他支持文件上获得,以便用户使用。额定容量可包括数字，或其他词、短语、字母数字字符组合、图标或向用户指示该电化学装置如何工作的标志。Exemplarily, the rated capacity of the electrochemical device can be obtained from the manufacturer or seller on the label, packaging, user manual, instruction manual, advertisement, marketing or other supporting documents of these products for user use. The rated capacity may include a number, or other words, phrases, alphanumeric character combinations, icons or symbols that indicate to the user how the electrochemical device works.
示例性地，18650电芯的额定容量可为2500毫安时(mAh)、2600毫安时(mAh)、2700毫安时(mAh)、2800毫安时(mAh)、2900毫安时(mAh)、3000毫安时(mAh)、3100毫安时(mAh)、3200毫安时(mAh)、3300毫安时(mAh)、3400毫安时(mAh)、3500毫安时(mAh)。示例性地，21700电芯的额定容量可为3500毫安时(mAh)、3600毫安时(mAh)、3700毫安时(mAh)、3800毫安时(mAh)、3900毫安时(mAh)、4000毫安时(mAh)、4100毫安时(mAh)、4200毫安时(mAh)、4300毫安时(mAh)、4400毫安时(mAh)、4500毫安时(mAh)。Exemplarily, the rated capacity of the 18650 battery cell can be 2500 mAh, 2600 mAh, 2700 mAh, 2800 mAh, 2900 mAh, 3000 mAh, 3100 mAh, 3200 mAh, 3300 mAh, 3400 mAh, and 3500 mAh. Exemplarily, the rated capacity of the 21700 battery cell can be 3500 mAh, 3600 mAh, 3700 mAh, 3800 mAh, 3900 mAh, 4000 mAh, 4100 mAh, 4200 mAh, 4300 mAh, 4400 mAh, and 4500 mAh.
示例性地，放电倍率＝电流/额定容量。示例性地，放电倍率在其总存储容量方面以Ah或mAh表示的电化学装置或电池包的放电速率。示例性地，1C的倍率表示在1小时利用所有的存储能量；0.5C的倍率表示在2小时利用所有的存储能量；10C的倍率表示在0.1小时利用所有的存储能量。Exemplarily, discharge rate = current / rated capacity. Exemplarily, the discharge rate is the rate of discharge of an electrochemical device or battery pack in terms of its total storage capacity expressed in Ah or mAh. Exemplarily, a rate of 1C means that all the stored energy is utilized in 1 hour; a rate of 0.5C means that all the stored energy is utilized in 2 hours; and a rate of 10C means that all the stored energy is utilized in 0.1 hours.
例如，放电倍率为xC，电化学装置从100％的SOC放电至0％的SOC的时间为t，t等于1/x小时。For example, if the discharge rate is xC, the time for the electrochemical device to discharge from 100% SOC to 0% SOC is t, where t is equal to 1/x hours.
示例性地，充电倍率＝电流/额定容量。示例性地，电化学装置的额定容量为4000毫安时，以0.5C充电倍率执行充电操作的过程中，充电电流为4000×0.5毫安。Exemplarily, charging rate=current/rated capacity. Exemplarily, when the rated capacity of the electrochemical device is 4000 mAh, during the charging operation at a 0.5C charging rate, the charging current is 4000×0.5 mAh.
电化学装置1000的放电容量可通过电池测试仪(Neware CT-4016-5V-100A)测得。例如，以第一放电倍率执行放电操作，持续放电操作至电化学装置1000的SOC为0％，放电操作的持续的时长为t，与第一放电倍率对应的电流为i，放电容量可为t×i。The discharge capacity of the electrochemical device 1000 can be measured by a battery tester (Neware CT-4016-5V-100A). For example, a discharge operation is performed at a first discharge rate, and the discharge operation is continued until the SOC of the electrochemical device 1000 is 0%. The duration of the discharge operation is t, and the current corresponding to the first discharge rate is i. The discharge capacity can be t×i.
作为示例，第一环境温度为恒温。例如，电化学装置1000可在恒温箱(科明EH-1000)中执行操作。As an example, the first environment temperature is a constant temperature. For example, the electrochemical device 1000 may be operated in a constant temperature box (Comin EH-1000).
作为示例，第一环境温度可为22℃、23℃、24℃、25℃、26℃、27℃或28℃。As an example, the first ambient temperature may be 22°C, 23°C, 24°C, 25°C, 26°C, 27°C or 28°C.
作为示例，第一放电倍率可为15C、16C、17C、17.5C、18C、19C或20C。As an example, the first discharge rate may be 15C, 16C, 17C, 17.5C, 18C, 19C, or 20C.
本申请实施例通过设置第一揉平区，可以增大过流能力，电化学装置电阻较小，在以15C-20C的高倍率进行放电时，电化学装置温升较低，有利于降低能量损耗，从而使电化学装置能够具有较高的放电容量，为用电设备提供更多的电能，改善电化学装置的放电性能。The embodiment of the present application can increase the current capacity by setting the first flattening zone. The resistance of the electrochemical device is small. When discharging at a high rate of 15C-20C, the temperature rise of the electrochemical device is low, which is beneficial to reducing energy loss. Therefore, the electrochemical device can have a higher discharge capacity, provide more electrical energy for electrical equipment, and improve the discharge performance of the electrochemical device.
在一些实施例中，电化学装置1000的放电容量与电化学装置1000的额定容量之比大于或等于90％。电化学装置1000能够在以15C-20C的高倍率进行放电时，具有更高的放电容量，为用电设备提供更多的电能。In some embodiments, the ratio of the discharge capacity of the electrochemical device 1000 to the rated capacity of the electrochemical device 1000 is greater than or equal to 90%. The electrochemical device 1000 can have a higher discharge capacity when discharged at a high rate of 15C-20C, providing more electrical energy for electrical equipment.
在一些实施例中，电化学装置1000的放电容量与电化学装置1000的额定容量之比大于或等于95％。电化学装置1000能够在以15C-20C的高倍率进行放电时，具有更高的放电容量，为用电设备提供更多的电能。In some embodiments, the ratio of the discharge capacity of the electrochemical device 1000 to the rated capacity of the electrochemical device 1000 is greater than or equal to 95%. The electrochemical device 1000 can have a higher discharge capacity when discharged at a high rate of 15C-20C, providing more electrical energy for electrical equipment.
在一些实施例中，电化学装置1000的放电容量与电化学装置1000的额定容量之比大于或等于98％。电化学装置1000能够在以15C-20C的高倍率进行放电时，具有更高的放电容量，为用电设备提供更多的电能。In some embodiments, the ratio of the discharge capacity of the electrochemical device 1000 to the rated capacity of the electrochemical device 1000 is greater than or equal to 98%. The electrochemical device 1000 can have a higher discharge capacity when discharged at a high rate of 15C-20C, providing more electrical energy for electrical equipment.
在一些实施例中，第一放电倍率在17.5C-20C的范围内。在以17.5C-20C的高倍率进行放电时，电化学装置1000的放电容量与电化学装置1000的额定容量之比大于或等于99％，可以为用电设备提供更多的电能。In some embodiments, the first discharge rate is in the range of 17.5C-20C. When discharged at a high rate of 17.5C-20C, the ratio of the discharge capacity of the electrochemical device 1000 to the rated capacity of the electrochemical device 1000 is greater than or equal to 99%, which can provide more electrical energy for electrical equipment.
在一些实施例中，第一环境温度为25℃。In some embodiments, the first ambient temperature is 25°C.
在一些实施例中，正极极片包括正极集流体和正极活性物质，正极活性物质设于正极集流体上，正极活性物质包括Li1+aNix1Coy1Mnz1O2或Li1+aNix2Coy2Alz2O2中的至少一种。其中，x1和x2均大于或等于0.8，y1和y2均大于0，z2和z3均大于0，x1+y1+z1＝1，x2+y2+z2＝1，-0.05≤a≤0.2。In some embodiments, the positive electrode plate includes a positive electrode current collector and a positive electrode active material, the positive electrode active material is disposed on the positive electrode current collector, and the positive electrode active material includes at least one of Li1+a Nix1 Coy1 Mnz1 O2 or Li1+a Nix2 Coy2 Alz2 O2. Wherein, x1 and x2 are both greater than or equal to 0.8, y1 and y2 are both greater than 0, z2 and z3 are both greater than 0, x1+y1+z1=1, x2+y2+z2=1, and -0.05≤a≤0.2.
在一些实施例中，x1和x2均大于或等于0.9。In some embodiments, x1 and x2 are both greater than or equal to 0.9.
在一些实施例中，正极活性物质包括LiNi0.8Co0.1Mn0.1O2、LiNi0.91Co0.04Mn0.05O2、LiNi0.92Co0.03Mn0.05O2、LiNi0.93Co0.02Mn0.05O2、LiNi0.94Co0.01Mn0.05O2、LiNi0.95Co0.01Mn0.04O2、LiNi0.8Co0.1Al0.1O2、LiNi0.91Co0.04Al0.05O2、LiNi0.92Co0.03Al0.05O2、LiNi0.93Co0.02Al0.05O2、LiNi0.94Co0.01Al0.05O2、LiNi0.95Co0.01Al0.04O2中的至少一种。In some embodiments, the positive electrode active material includes LiNi0.8 Co0.1 Mn0.1 O2 , LiNi0.91 Co0.04 Mn0.05 O2 , LiNi0.92 Co0.03 Mn0.05 O2 , LiNi0.93 Co0.02 Mn0.05 O2 , LiNi0.94 Co0.01 Mn0.05 O2 , LiNi0.95 Co0.01 Mn0.04 O2 , LiNi0.8 Co0.1 Al0.1 O2 , LiNi0.91 Co0.04 Al0.05 O2 , LiNi0.92 Co0.03 Al0.05 O2 , LiNi0.93 Co0.02 Al0.05 O2 , at least one of LiNi0.94 Co0.01 Al0.05 O2 , and LiNi0.95 Co0.01 Al0.04 O2 .
在一些实施例中，正极活性物质包括正极活性材料、粘接剂和导电剂，正极活性材料包括Li1+aNix1Coy1Mnz1O2或Li1+aNix2Coy2Alz2O2中的至少一种。In some embodiments, the positive electrode active material includes a positiveelectrode active material,a binder and a conductive agent, and the positiveelectrode active material includes at leastoneof Li1+aNix1Coy1Mnz1O2 or Li1+aNix2Coy2Alz2O2.
在一些实施例中，粘接剂包括聚丙烯酸(PAA)、聚丙烯腈(PAN)、聚偏二氟乙烯(PVDF)、聚四氟乙烯(PTFE)或聚酰胺(PA)中的至少一种。In some embodiments, the binder includes at least one of polyacrylic acid (PAA), polyacrylonitrile (PAN), polyvinylidene fluoride (PVDF), polytetrafluoroethylene (PTFE), or polyamide (PA).
在一些实施例中，导电剂包括乙炔黑、导电炭黑、碳纳米管、碳纤维、鳞片石墨、科琴黑或石墨烯中的至少一种。In some embodiments, the conductive agent includes at least one of acetylene black, conductive carbon black, carbon nanotubes, carbon fibers, flake graphite, Ketjen black, or graphene.
在一些实施例中，在正极活性物质中，正极活性材料的质量百分含量为90％-98％，粘接剂的质量百分含量为1.25％-5％，导电剂的质量百分含量为0.75％-5％。In some embodiments, in the positive electrode active material, the mass percentage of the positive electrode active material is 90%-98%, the mass percentage of the binder is 1.25%-5%, and the mass percentage of the conductive agent is 0.75%-5%.
在一些实施例中，负极极片包括负极集流体和负极活性物质，负极活性物质设于负极集流体上，负极活性物质包括人造石墨和/或天然石墨。In some embodiments, the negative electrode plate includes a negative electrode current collector and a negative electrode active material, the negative electrode active material is disposed on the negative electrode current collector, and the negative electrode active material includes artificial graphite and/or natural graphite.
在一些实施例中，负极活性物质中也包括粘接剂和导电剂。In some embodiments, the negative electrode active material also includes a binder and a conductive agent.
在一些实施例中，第一极片11为正极极片，第一集流体111为正极集流体，第一活性物质112为正极活性物质。在另一些实施例中，第一极片11为负极极片，第一集流体111为负极集流体，第一活性物质112为负极活性物质。In some embodiments, the first electrode sheet 11 is a positive electrode sheet, the first current collector 111 is a positive electrode current collector, and the first active material 112 is a positive electrode active material. In other embodiments, the first electrode sheet 11 is a negative electrode sheet, the first current collector 111 is a negative electrode current collector, and the first active material 112 is a negative electrode active material.
在一些实施例中，电化学装置1000还包括容纳于壳体2内的电解液。电解液包括六氟磷酸锂(LiPF6)和氟代碳酸乙烯酯(FEC)，基于电解液的质量，六氟磷酸锂的质量百分含量为12％-16％，氟代碳酸乙烯酯的质量百分含量为0.8％-1.5％。In some embodiments, the electrochemical device 1000 further includes an electrolyte contained in the housing 2. The electrolyte includes lithium hexafluorophosphate (LiPF6 ) and fluoroethylene carbonate (FEC), and based on the mass of the electrolyte, the mass percentage of lithium hexafluorophosphate is 12%-16%, and the mass percentage of fluoroethylene carbonate is 0.8%-1.5%.
电解液还包括溶剂。示例性地，电解液的溶剂选用碳酸乙烯酯(EC)和碳酸甲乙酯(EMC)的混合溶剂(EC：EMC质量比＝70：30)。溶质选用六氟磷酸锂(LiPF6)，添加剂选用氟代碳酸乙烯酯(FEC)。可选地，基于电解液的质量，LiPF6的质量百分含量为15％，FEC的质量百分含量为1％。The electrolyte also includes a solvent. Exemplarily, the solvent of the electrolyte is a mixed solvent of ethylene carbonate (EC) and ethyl methyl carbonate (EMC) (EC:EMC mass ratio = 70:30). The solute is lithium hexafluorophosphate (LiPF6 ), and the additive is fluoroethylene carbonate (FEC). Optionally, based on the mass of the electrolyte, the mass percentage of LiPF6 is 15%, and the mass percentage of FEC is 1%.
FEC作为电解液添加剂，有利于提升SEI膜的性能，形成紧密结构层但又不增加阻抗，能阻止电解液进一步分解，提高电化学装置的放电性能。As an electrolyte additive, FEC is beneficial to improving the performance of the SEI film, forming a tight structure layer without increasing impedance, preventing further decomposition of the electrolyte, and improving the discharge performance of the electrochemical device.
在一些实施例中，电化学装置1000为圆柱电芯。圆柱电芯生产工艺成熟、产品良率较高、散热性能好。In some embodiments, the electrochemical device 1000 is a cylindrical battery cell, which has a mature production process, a high product yield, and good heat dissipation performance.
在一些实施例中，圆柱电芯的直径为17mm-22mm。可选地，圆柱电芯的直径为17mm、18mm、19mm、20mm、21mm或22mm。In some embodiments, the diameter of the cylindrical battery cell is 17 mm to 22 mm. Optionally, the diameter of the cylindrical battery cell is 17 mm, 18 mm, 19 mm, 20 mm, 21 mm or 22 mm.
在一些实施例中，圆柱电芯的高度为64mm-72mm。可选地，圆柱电芯的高度为64mm、65mm、66mm、67mm、68mm、69mm、70mm、71mm或72mm。In some embodiments, the height of the cylindrical battery cell is 64 mm-72 mm. Optionally, the height of the cylindrical battery cell is 64 mm, 65 mm, 66 mm, 67 mm, 68 mm, 69 mm, 70 mm, 71 mm or 72 mm.
在一些实施例中，电化学装置1000为18650型电芯或21700型电芯。In some embodiments, the electrochemical device 1000 is a 18650 type battery cell or a 21700 type battery cell.
在一些实施例中，电化学装置1000的额定容量为2500毫安时(mAh)-4500毫安时(mAh)。可选地，电化学装置的额定容量为2500毫安时(mAh)、2600毫安时(mAh)、2700毫安时(mAh)、2800毫安时(mAh)、2900毫安时(mAh)、3000毫安时(mAh)、3100毫安时(mAh)、3200毫安时(mAh)、3300毫安时(mAh)、3400毫安时(mAh)、3500毫安时(mAh)、3600毫安时(mAh)、3700毫安时(mAh)、3800毫安时(mAh)、3900毫安时(mAh)、4000毫安时(mAh)、4100毫安时(mAh)、4200毫安时(mAh)、4300毫安时(mAh)、4400毫安时(mAh)或4500毫安时(mAh)。In some embodiments, the rated capacity of the electrochemical device 1000 is 2500 mAh to 4500 mAh. Optionally, the rated capacity of the electrochemical device is 2500 mAh, 2600 mAh, 2700 mAh, 2800 mAh, 2900 mAh, 3000 mAh, 3100 mAh, 3200 mAh, 3300 mAh, 3400 mAh, 3500 mAh, 3600 mAh, 3700 mAh, 3800 mAh, 3900 mAh, 4000 mAh, 4100 mAh, 4200 mAh, 4300 mAh, 4400 mAh or 4500 mAh.
在一些实施例中，在第一环境温度下，电化学装置1000的直流电阻小于或等于10毫欧。In some embodiments, at the first ambient temperature, the DC resistance of the electrochemical device 1000 is less than or equal to 10 milliohms.
示例性地，电化学装置1000的直流电阻的测试方式如下：Exemplarily, the DC resistance of the electrochemical device 1000 is tested as follows:
在25℃下，电化学装置以0.5C恒流放电至该电化学装置的放电截止电压，然后以0.5C恒流充电至该电化学装置的充电截止电压，然后以充电截止电压恒压充电至0.05C，此时该电化学装置处于100％的SOC；At 25° C., the electrochemical device is discharged at a constant current of 0.5 C to a discharge cut-off voltage of the electrochemical device, then charged at a constant current of 0.5 C to a charge cut-off voltage of the electrochemical device, and then charged at a constant voltage of the charge cut-off voltage to 0.05 C, at which time the electrochemical device is at 100% SOC;
在第一环境温度下静置2小时；Standing at the first ambient temperature for 2 hours;
在第一环境温度下，以与0.1C倍率对应的电流i1放电10s，测得电压V1；然后以与1C倍率对应的电流i2放电1s，并测得电压V2；At the first ambient temperature, the battery is discharged for 10 seconds at a current i1 corresponding to a 0.1C rate, and a voltage V1 is measured; then, the battery is discharged for 1 second at a current i2 corresponding to a 1C rate, and a voltage V2 is measured;
电化学装置的直流电阻为(V1-V2)/(i2-i1)。The DC resistance of the electrochemical device is (V1-V2)/(i2-i1).
本申请的电化学装置1000具有较小的直流电阻，电化学装置1000在以高倍率放电过程中温升较低，有利于降低能量损耗，提升电化学装置的放电容量，改善电化学装置的放电性能。The electrochemical device 1000 of the present application has a relatively small DC resistance, and the temperature rise of the electrochemical device 1000 is relatively low during high-rate discharge, which is beneficial to reducing energy loss, increasing the discharge capacity of the electrochemical device, and improving the discharge performance of the electrochemical device.
在一些实施例中，沿第一极片11展开后的宽度方向Y，第一空箔区111b的尺寸为W1，第一集流体111的总尺寸为W2，W1和W2满足：0.05≤W1/W2≤0.1。In some embodiments, along the width direction Y after the first electrode sheet 11 is unfolded, the size of the first empty foil area 111b is W1, the total size of the first current collector 111 is W2, and W1 and W2 satisfy: 0.05≤W1/W2≤0.1.
将W1/W2限定为大于或等于0.05，可以使第一空箔区111b具有较大的宽度，便于实现第一空箔区111b与其它导电结构的连接。将W1/W2限定为小于或等于0.1，可以为第一活性物质112预留更多的空间，减少能量密度的损失。By limiting W1/W2 to be greater than or equal to 0.05, the first empty foil area 111b can have a larger width, which facilitates the connection between the first empty foil area 111b and other conductive structures. By limiting W1/W2 to be less than or equal to 0.1, more space can be reserved for the first active material 112, reducing the loss of energy density.
另外，在对第一空箔区111b进行揉平处理时，第一空箔区111b会弯折变形；本申请实施例使W1/W2大于或等于0.05，以在揉平时减小第一活性物质112的受力，降低第一活性物质112变形、掉粉的风险。In addition, when the first empty foil area 111b is flattened, the first empty foil area 111b will bend and deform. In the embodiment of the present application, W1/W2 is greater than or equal to 0.05 to reduce the force on the first active material 112 during flattening, thereby reducing the risk of deformation and powder loss of the first active material 112.
可选地，W1/W2可为0.05、0.06、0.07、0.08、0.09或0.1。Alternatively, W1/W2 may be 0.05, 0.06, 0.07, 0.08, 0.09 or 0.1.
在一些实施例中，沿第一极片11展开后的宽度方向Y，第一揉平区111c的尺寸为W4，0.6≤W4/W1≤0.95。In some embodiments, along the width direction Y of the unfolded first pole piece 11 , the size of the first flattened area 111 c is W4, and 0.6≤W4/W1≤0.95.
将W4/W1限定为大于或等于0.6，可以增大第一空箔区111b在揉平过程中的受压区域，减小电极组件1的轴向尺寸，提高空间利用率并使第一揉平区111c更为致密。将W4/W1限定为小于或等于0.95，可以在揉平过程中，减小传导至第一活性物质112的力，降低第一活性物质112脱落的风险。By limiting W4/W1 to be greater than or equal to 0.6, the pressure area of the first empty foil area 111b during the flattening process can be increased, the axial size of the electrode assembly 1 can be reduced, the space utilization rate can be improved, and the first flattened area 111c can be made denser. By limiting W4/W1 to be less than or equal to 0.95, the force transmitted to the first active material 112 can be reduced during the flattening process, reducing the risk of the first active material 112 falling off.
可选地，W4/W1为0.6、0.7、0.8、0.9或0.95。Optionally, W4/W1 is 0.6, 0.7, 0.8, 0.9 or 0.95.
在一些实施例中，沿第一极片11展开后的长度方向X，第一空箔区111b的尺寸为L1，第一主体区111a的尺寸为L2。L1和L2满足：0.8≤L1/L2≤1。In some embodiments, along the length direction X after the first electrode sheet 11 is unfolded, the size of the first empty foil area 111b is L1, and the size of the first main area 111a is L2. L1 and L2 satisfy: 0.8≤L1/L2≤1.
沿第一极片11展开后的长度方向X，L1为第一空箔区111b展开后的最大尺寸。Along the length direction X of the first pole piece 11 after it is unfolded, L1 is the maximum size of the first empty foil area 111b after it is unfolded.
示例性地，第一极片11展开可以是将第一极片11展开成平整的片状结构，对应地，第一揉平区111c也展平。Exemplarily, unfolding the first pole piece 11 may be unfolding the first pole piece 11 into a flat sheet structure, and correspondingly, the first flattened area 111 c is also flattened.
第一空箔区111b具有较大的过流面积，在电化学装置1000以高倍率放电时，第一空箔区111b可以通过较大的电流，从而减小第一空箔区111b的产热、降低第一空箔区111b熔断的风险。The first empty foil region 111b has a larger flow area. When the electrochemical device 1000 is discharged at a high rate, a larger current can pass through the first empty foil region 111b, thereby reducing heat generation of the first empty foil region 111b and reducing the risk of the first empty foil region 111b fusing.
可选地，L1/L2可为0.8、0.85、0.9、0.95或1。Optionally, L1/L2 may be 0.8, 0.85, 0.9, 0.95 or 1.
在一些实施例中，0.9≤L1/L2≤0.95，可进一步提高第一空箔区111b的过流能力，并在第一空箔区111b满足过流能力的前提下，减小第一空箔区111b的尺寸，减小第一空箔区111b占用的空间和重量，提高能量密度，并有利于电解液的浸润。In some embodiments, 0.9≤L1/L2≤0.95, which can further improve the flow capacity of the first empty foil area 111b, and on the premise that the first empty foil area 111b meets the flow capacity, reduce the size of the first empty foil area 111b, reduce the space and weight occupied by the first empty foil area 111b, improve the energy density, and facilitate the infiltration of the electrolyte.
在一些实施例中，第一空箔区111b沿卷绕方向V连续设置并卷绕为多圈。第一空箔区111b连续卷绕，可增大第一空箔区111b的整体强度；第一空箔区111b整体连续，电流可以在第一空箔区111b的不同区域传输，并提高第一极片11的电流一致性。In some embodiments, the first empty foil area 111b is continuously arranged and wound into multiple turns along the winding direction V. The first empty foil area 111b is continuously wound, which can increase the overall strength of the first empty foil area 111b; the first empty foil area 111b is continuous as a whole, and the current can be transmitted in different areas of the first empty foil area 111b, thereby improving the current consistency of the first pole piece 11.
在一些实施例中，电化学装置1000还包括集流盘4，集流盘4连接电极端子3和电极组件1。示例性地，集流盘4连接电极端子3和第一极片11。In some embodiments, the electrochemical device 1000 further includes a current collecting plate 4, which connects the electrode terminal 3 and the electrode assembly 1. Exemplarily, the current collecting plate 4 connects the electrode terminal 3 and the first electrode sheet 11.
在一些实施例中，电化学装置1000还包括设置于壳体2的电极端子3以及连接第一揉平区111c和电极端子3的集流盘4。In some embodiments, the electrochemical device 1000 further includes an electrode terminal 3 disposed on the housing 2 and a current collecting plate 4 connecting the first flattened area 111 c and the electrode terminal 3 .
第一揉平区111c具有致密的端面，将第一揉平区111c与集流盘4连接，可以提高连接强度。The first flattened area 111 c has a dense end surface, and the first flattened area 111 c is connected to the current collecting plate 4 to improve the connection strength.
在一些实施例中，集流盘4焊接于第一揉平区111c。本申请实施例可以降低虚焊风险，提高焊接强度，并降低因漏激光而烧伤隔膜13的风险，提高安全性。In some embodiments, the current collecting plate 4 is welded to the first flattened area 111c. The embodiments of the present application can reduce the risk of cold welding, improve welding strength, and reduce the risk of burning the diaphragm 13 due to laser leakage, thereby improving safety.
在一些实施例中，集流盘4设有通孔41。在注液工序中，电解液可以穿过通孔41并浸润电极组件1，改善浸润性。在电化学装置1000因过热、过充电、短路或其它原因而失效时，电极组件1会释放气体；通过开设通孔41，可以为气体提供通道，从而快速将气体排出到电化学装置的外部，降低爆炸风险。In some embodiments, the collector plate 4 is provided with a through hole 41. During the injection process, the electrolyte can pass through the through hole 41 and infiltrate the electrode assembly 1 to improve wettability. When the electrochemical device 1000 fails due to overheating, overcharging, short circuit or other reasons, the electrode assembly 1 will release gas; by providing the through hole 41, a channel can be provided for the gas, so that the gas can be quickly discharged to the outside of the electrochemical device, reducing the risk of explosion.
在一些实施例中，电化学装置1000还包括绝缘件6，绝缘件6环绕在第一揉平区111c的外侧。In some embodiments, the electrochemical device 1000 further includes an insulating member 6 , which surrounds the outer side of the first flattened region 111 c .
绝缘片6可以将第一揉平区111c与壳体2隔开，以降低短路风险。绝缘片6还可以从外周收拢第一揉平区111c，降低第一揉平区111c散开的风险。The insulating sheet 6 can separate the first flattened area 111c from the housing 2 to reduce the risk of short circuit. The insulating sheet 6 can also gather the first flattened area 111c from the periphery to reduce the risk of the first flattened area 111c spreading out.
在一些实施例中，绝缘件6至少环绕在第一揉平区111c一周。In some embodiments, the insulating member 6 surrounds the first flattened area 111 c for at least one circle.
在一些实施例中，绝缘件6的环绕接口处设有重叠区域61。绝缘件61可以在重叠区域61连接，以降低绝缘件6从第一揉平区111c上脱落的风险。In some embodiments, an overlapping area 61 is provided at the surrounding interface of the insulating member 6. The insulating member 61 can be connected at the overlapping area 61 to reduce the risk of the insulating member 6 falling off from the first flattened area 111c.
在一些实施例中，绝缘件6在重叠区域61粘接。In some embodiments, the insulating element 6 is bonded in the overlapping area 61 .
在一些实施例中，绝缘件6包括胶带。In some embodiments, the insulating member 6 comprises adhesive tape.
在一些实施例中，重叠区域61避开第一揉平区111c沿卷绕方向V的外端。示例性地，在第一揉平区111c的径向上，第一揉平区111c沿卷绕方向的外端不与重叠区域61交叠，缓解重叠后的厚度增加导致径向上的尺寸的增大而降低能量密度的问题。In some embodiments, the overlapping region 61 avoids the outer end of the first flattened region 111c along the winding direction V. Exemplarily, in the radial direction of the first flattened region 111c, the outer end of the first flattened region 111c along the winding direction does not overlap with the overlapping region 61, alleviating the problem of increased radial dimensions and reduced energy density caused by increased thickness after overlap.
在连接绝缘件6时，需要从外侧挤压重叠区域61。将重叠区域61避开第一揉平区111c的外端，有利于减小电化学装置膨胀时，第一揉平区111c的外端受到挤压导致析锂等问题。When connecting the insulating member 6, the overlapping area 61 needs to be squeezed from the outside. The overlapping area 61 is kept away from the outer end of the first flattened area 111c, which is beneficial to reduce the problem of lithium deposition caused by the outer end of the first flattened area 111c being squeezed when the electrochemical device expands.
参照图10和图11，在一些实施例中，第一空箔区111b沿卷绕方向V的外端的角部设有第一切口G1。10 and 11 , in some embodiments, a first cutout G1 is provided at a corner of an outer end of the first empty foil region 111 b along the winding direction V.
示例性地，第一切口G1位于第一空箔区111b沿第一极片11展开后的长度方向X的一端。Exemplarily, the first cutout G1 is located at one end of the first empty foil area 111 b along the length direction X after the first pole piece 11 is unfolded.
在第一空箔区111b通过揉平形成第一揉平区111c后，可以在第一揉平区111c外周贴附绝缘件6；通过设置第一切口G1，可降低第一空箔区111b的外端的尖角过大导致刺破绝缘件6的风险，有利于减少绝缘件6的使用量，提高能量密度。After the first empty foil area 111b is flattened to form the first flattened area 111c, the insulating member 6 can be attached to the periphery of the first flattened area 111c; by setting the first incision G1, the risk of the outer end of the first empty foil area 111b being too sharp and puncturing the insulating member 6 can be reduced, which is beneficial to reducing the use of the insulating member 6 and improving the energy density.
在一些实施例中，第一空箔区111b沿卷绕方向V的内端的角部处设有第二切口G2。In some embodiments, a second cutout G2 is provided at a corner of the inner end of the first empty foil region 111 b along the winding direction V.
示例性地，第一切口G1和第二切口G2分别位于第一空箔区111b沿第一极片11展开后的长度方向X的两端。Exemplarily, the first cutout G1 and the second cutout G2 are respectively located at two ends of the first empty foil area 111 b along the length direction X after the first pole piece 11 is unfolded.
在一些实施例中，沿第一极片11展开后的长度方向X，第一切口G1的尺寸为La；La和W1满足：0.2≤La/W1≤4。In some embodiments, along the length direction X after the first pole piece 11 is unfolded, the size of the first cutout G1 is La; La and W1 satisfy: 0.2≤La/W1≤4.
将La/W1限定为大于或等于0.2，可以在揉平过程中减少空箔材料的堆积，降低包覆第一空箔区111b的绝缘件被刺破的风险，提高安全性。将La/W1限定为小于或等于4，可以降低第一切口G1对第一空箔区111b的过流能力的影响。By limiting La/W1 to be greater than or equal to 0.2, the accumulation of the empty foil material can be reduced during the flattening process, the risk of the insulating member covering the first empty foil area 111b being punctured can be reduced, and safety can be improved. By limiting La/W1 to be less than or equal to 4, the influence of the first cutout G1 on the current carrying capacity of the first empty foil area 111b can be reduced.
可选地，La/W1为0.2、0.3、0.5、0.8、1.0、1.5、1.8、2、2.5、3、3.5或4。Optionally, La/W1 is 0.2, 0.3, 0.5, 0.8, 1.0, 1.5, 1.8, 2, 2.5, 3, 3.5 or 4.
在一些实施例中，0.5≤La/W1≤2。In some embodiments, 0.5≤La/W1≤2.
在一些实施例中，沿第一极片11展开后的宽度方向Y，第一切口G1的尺寸为W3；W3和W1满足：0.2≤W3/W1≤1。In some embodiments, along the width direction Y of the unfolded first pole piece 11 , the size of the first cutout G1 is W3 ; W3 and W1 satisfy: 0.2≤W3/W1≤1.
将W3/W1限定为大于或等于0.2，可以在揉平过程中减少空箔材料的堆积，降低包覆第一空箔区111b的绝缘件被刺破的风险，提高安全性。将W3/W1限定为小于或等于1，可以降低第一切口G1开设到第一主体区111a的风险，减少第一活性物质112的损失。By limiting W3/W1 to be greater than or equal to 0.2, the accumulation of the empty foil material can be reduced during the flattening process, the risk of the insulating member covering the first empty foil area 111b being punctured can be reduced, and safety can be improved. By limiting W3/W1 to be less than or equal to 1, the risk of the first incision G1 being opened to the first main body area 111a can be reduced, and the loss of the first active material 112 can be reduced.
可选地，W3/W1为0.2、0.3、0.4、0.5、0.6、0.7、0.8、0.9或1。Optionally, W3/W1 is 0.2, 0.3, 0.4, 0.5, 0.6, 0.7, 0.8, 0.9 or 1.
在一些实施例中，第一切口G1和第二切口G2形状尺寸均相同。In some embodiments, the first incision G1 and the second incision G2 have the same shape and size.
在一些实施例中，可通过在第一空箔区111b的角部开设倒角，以形成第一切口G1。In some embodiments, the first cutout G1 may be formed by chamfering a corner of the first empty foil area 111 b .
在一些实施例中，第一切口G1可为三角切口。示例性地，可通过在第一空箔区111b倒斜角，以形成三角切口。In some embodiments, the first cutout G1 may be a triangular cutout. For example, the triangular cutout may be formed by chamfering the first empty foil area 111 b.
参照图12，在一些实施例中，第一切口G1可为弧形切口。示例性地，可通过在第一空箔区111b倒圆角，以形成弧形切口。12 , in some embodiments, the first cutout G1 may be an arc-shaped cutout. For example, the arc-shaped cutout may be formed by rounding the first empty foil area 111 b.
参照图13，在一些实施例中，第一切口G1可为矩形切口。13 , in some embodiments, the first cutout G1 may be a rectangular cutout.
在一些实施例中，参照图14，第一空箔区111b包括多个第一子极耳1111，沿第一极片11展开后的长度方向X，多个第一子极耳1111分离设置。In some embodiments, referring to FIG. 14 , the first empty foil region 111 b includes a plurality of first sub-electrode tabs 1111 , and the plurality of first sub-electrode tabs 1111 are separately disposed along the length direction X after the first pole piece 11 is unfolded.
多个第一子极耳1111分离设置，在揉平过程中，各第一子极耳1111更容易弯折变形，减小揉平过程中的应力。The plurality of first sub-electrode tabs 1111 are separately arranged, and during the flattening process, each first sub-electrode tab 1111 is more easily bent and deformed, thereby reducing the stress during the flattening process.
多个第一子极耳1111沿卷绕方向V不连续，相邻的第一子极耳1111在卷绕方向V上可以接触，也可以不接触。The plurality of first sub-electrode tabs 1111 are discontinuous along the winding direction V. Adjacent first sub-electrode tabs 1111 may or may not be in contact with each other in the winding direction V.
在一些实施例中，沿第一极片11展开后的长度方向X，相邻的第一子极耳1111之间的最小间距D为0mm-66mm。In some embodiments, along the length direction X after the first pole piece 11 is unfolded, the minimum distance D between adjacent first sub-pole ears 1111 is 0 mm-66 mm.
可选地，D可为0mm、1mm、5mm、8mm、10mm、20mm、30mm、40mm、50mm、60mm或66mm。Alternatively, D may be 0 mm, 1 mm, 5 mm, 8 mm, 10 mm, 20 mm, 30 mm, 40 mm, 50 mm, 60 mm, or 66 mm.
本申请实施例将D限定为0mm-66mm，可在分离相邻的第一子极耳1111的情况下，利于电解液的浸润，且减小第一空箔区111b的过流面积的损失。In the embodiment of the present application, D is limited to 0 mm-66 mm, which can facilitate the infiltration of the electrolyte and reduce the loss of the flow area of the first empty foil area 111 b when separating the adjacent first sub-electrode ears 1111.
在一些实施例中，沿第一极片11展开后的长度方向X，多个第一子极耳1111的尺寸之和为L3，第一主体区111a的尺寸为L2，L3和L2满足：0.8≤L3/L2≤1。In some embodiments, along the length direction X after the first pole piece 11 is unfolded, the sum of the sizes of the plurality of first sub-pole ears 1111 is L3, the size of the first main region 111a is L2, and L3 and L2 satisfy: 0.8≤L3/L2≤1.
在一些实施例中，沿第一极片11展开后的长度方向X，L3为多个第一子极耳1111的最小尺寸之和。In some embodiments, along the length direction X after the first pole piece 11 is unfolded, L3 is the sum of the minimum dimensions of the plurality of first sub-pole tabs 1111 .
示例性地，n个第一子极耳1111沿第一极片展开后的长度方向X的最小尺寸分别为K1、K2、……、Kn，n为大于1的正整数，L3＝K1+K2+……+Kn。例如，如图14所示，第一子极耳1111为四个，L3＝K1+K2+K3+K4。Exemplarily, the minimum dimensions of the n first sub-electrode tabs 1111 along the length direction X after the first pole piece is unfolded are K1, K2, ..., Kn, respectively, n is a positive integer greater than 1, and L3 = K1 + K2 + ... + Kn. For example, as shown in FIG. 14 , there are four first sub-electrode tabs 1111, and L3 = K1 + K2 + K3 + K4.
多个第一子极耳1111具有较大的过流面积，在电化学装置1000以高倍率放电时，可以减少第一子极耳1111的产热、降低第一子极耳1111熔断的风险。The plurality of first sub-electrode tabs 1111 have a large flow area, which can reduce the heat generated by the first sub-electrode tabs 1111 and the risk of the first sub-electrode tabs 1111 fusing when the electrochemical device 1000 is discharged at a high rate.
可选地，L3/L2可为0.8、0.85、0.9、0.95或1。Optionally, L3/L2 may be 0.8, 0.85, 0.9, 0.95 or 1.
在一些实施例中，0.9≤L3/L2≤0.95。In some embodiments, 0.9≤L3/L2≤0.95.
本申请实施例可增大第一子极耳1111的过流能力，并在相邻的第一子极耳1111之间预留更多的间隙，降低第一子极耳1111在揉平过程中的阻力，且利于电解液的浸润。The embodiment of the present application can increase the current carrying capacity of the first sub-electrode lug 1111 and reserve more gaps between adjacent first sub-electrode lugs 1111, thereby reducing the resistance of the first sub-electrode lug 1111 during the flattening process and facilitating the infiltration of the electrolyte.
在一些实施例中，第一子极耳1111的数量大于或等于4。示例性地，第一子极耳1111的数量为4、5、6、8、10、12、15、18或20。In some embodiments, the number of the first sub-electrode tabs 1111 is greater than or equal to 4. Exemplarily, the number of the first sub-electrode tabs 1111 is 4, 5, 6, 8, 10, 12, 15, 18 or 20.
在多个第一子极耳1111之和L3一定的前提下，通过增加第一子极耳1111的数量，降低单个第一子极耳1111揉平的阻力。Under the premise that the sum L3 of the plurality of first sub-electrode tabs 1111 is constant, the resistance to flattening a single first sub-electrode tab 1111 is reduced by increasing the number of the first sub-electrode tabs 1111 .
在一些实施例中，沿第一极片11展开后的长度方向X，多个第一子极耳1111以等间隔的方式设置。In some embodiments, along the length direction X after the first pole piece 11 is unfolded, the plurality of first sub-pole tabs 1111 are arranged at equal intervals.
在一些实施例中，沿第一极片11展开后的长度方向X，多个第一子极耳1111的尺寸相同。In some embodiments, along the length direction X after the first pole piece 11 is unfolded, the sizes of the plurality of first sub-pole tabs 1111 are the same.
在一些实施例中，第一空箔区111b还包括过渡部(未示出)，过渡部沿卷绕方向V连续设置，并连接第一主体区111a和多个第一子极耳1111。In some embodiments, the first empty foil region 111 b further includes a transition portion (not shown), which is continuously disposed along the winding direction V and connects the first main body region 111 a and the plurality of first sub-electrode tabs 1111 .
在一些实施例中，沿第一极片11展开后的长度方向X，过渡部的尺寸等于第一主体区111a的尺寸。In some embodiments, along the length direction X after the first pole piece 11 is unfolded, the size of the transition portion is equal to the size of the first main body region 111 a .
参照图16，在一些实施例中，沿第一极片11展开后的长度方向X，第一空箔区111b的内端E1和第一主体区111a的内端E3间隔第一距离D1，第一主体区111a的尺寸为L2。0＜D1/L2＜0.2。16 , in some embodiments, along the length direction X after the first pole piece 11 is unfolded, the inner end E1 of the first empty foil area 111b and the inner end E3 of the first main area 111a are separated by a first distance D1, and the size of the first main area 111a is L2. 0＜D1/L2＜0.2.
电极组件1卷绕成型后，中部形成中心孔10c。在注液时，中心孔10c可以作为注液通道。本申请实施例将D1/L2设置为大于0，可以增大第一空箔区111b与中心孔10c的距离，降低第一空箔区111b在揉平过程中遮挡中心孔10c的风险。After the electrode assembly 1 is wound, a central hole 10c is formed in the middle. When injecting liquid, the central hole 10c can be used as an injection channel. In the embodiment of the present application, D1/L2 is set to be greater than 0, which can increase the distance between the first empty foil area 111b and the central hole 10c and reduce the risk of the first empty foil area 111b blocking the central hole 10c during the flattening process.
本申请实施例将D1/L2设置为小于0.2，可以减少第一空箔区111b的过流能力的损失，使电化学装置1000能够以大倍率进行放电。In the embodiment of the present application, D1 / L2 is set to be less than 0.2, which can reduce the loss of the current capacity of the first empty foil area 111 b and enable the electrochemical device 1000 to discharge at a large rate.
在一些实施例中，D1/L2可为0.05、0.1、0.15或0.18。In some embodiments, D1/L2 may be 0.05, 0.1, 0.15, or 0.18.
在一些实施例中，0.05≤D1/L2≤0.1，可以降低对第一空箔区111b进行揉平的阻力，提高电解液的浸润性，并减少第一空箔区111b的过流能力的损失，使电化学装置1000能够以大倍率进行放电。In some embodiments, 0.05≤D1/L2≤0.1, which can reduce the resistance to flattening the first empty foil area 111b, improve the wettability of the electrolyte, and reduce the loss of the current capacity of the first empty foil area 111b, so that the electrochemical device 1000 can be discharged at a large rate.
参照图16，在一些实施例中，沿第一极片11展开后的长度方向X，第一空箔区111b的外端E2和第一主体区111a的外端E4间隔第二距离D2，第一主体区111a的尺寸为L2，0＜D2/L2＜0.2。16 , in some embodiments, along the length direction X after the first pole piece 11 is unfolded, the outer end E2 of the first empty foil area 111b and the outer end E4 of the first main area 111a are spaced apart by a second distance D2, and the size of the first main area 111a is L2, 0＜D2/L2＜0.2.
本申请实施例将D2/L2设置为大于0，可以减小第一空箔区111b卷绕形成的柱状结构的外径，便于外部工装从外部对第一空箔区111b进行揉平。本申请实施例将D2/L2设置为小于0.2，可以减少第一空箔区111b的过流能力的损失，使电化学装置1000能够以大倍率进行放电。In the embodiment of the present application, D2/L2 is set to be greater than 0, which can reduce the outer diameter of the columnar structure formed by the winding of the first empty foil area 111b, making it easier for external tooling to flatten the first empty foil area 111b from the outside. In the embodiment of the present application, D2/L2 is set to be less than 0.2, which can reduce the loss of the current capacity of the first empty foil area 111b, so that the electrochemical device 1000 can be discharged at a large rate.
在一些实施例中，D2/L2可为0.05、0.1、0.15或0.18。In some embodiments, D2/L2 may be 0.05, 0.1, 0.15, or 0.18.
在一些实施例中，0.05≤D2/L2≤0.1，可以降低对第一空箔区111b进行揉平的阻力，提高电解液的浸润性，并减少第一空箔区111b的过流能力的损失，使电化学装置1000能够以大倍率进行放电。In some embodiments, 0.05≤D2/L2≤0.1, which can reduce the resistance to flattening the first empty foil area 111b, improve the wettability of the electrolyte, and reduce the loss of the current capacity of the first empty foil area 111b, so that the electrochemical device 1000 can be discharged at a large rate.
在一些实施例中，参照图17，沿第一极片11展开后的长度方向X，第一空箔区111b的内端E1和第一主体区111a的内端E3间隔第一距离D1，第一空箔区111b的外端E2和第一主体区111a的外端E4间隔第二距离D2。0＜(D1+D2)/L2＜0.2，D1＞0，D2＞0。In some embodiments, referring to Figure 17, along the length direction X after the first pole piece 11 is unfolded, the inner end E1 of the first empty foil area 111b and the inner end E3 of the first main area 111a are separated by a first distance D1, and the outer end E2 of the first empty foil area 111b and the outer end E4 of the first main area 111a are separated by a second distance D2. 0＜(D1+D2)/L2＜0.2, D1＞0, D2＞0.
可选地，0.05≤(D1+D2)/L2≤0.1。Optionally, 0.05≤(D1+D2)/L2≤0.1.
参照图2和图18，在一些实施例中，第一空箔区111b包括沿第一极片11展开后的长度方向X布置的第一极耳区Z1、第二极耳区Z2和第三极耳区Z3，第一极耳区Z1、第二极耳区Z2和第三极耳区Z3中的每一者均包括至少两个第一子极耳1111。2 and 18 , in some embodiments, the first empty foil area 111b includes a first pole lug area Z1, a second pole lug area Z2 and a third pole lug area Z3 arranged along the length direction X after the first pole piece 11 is unfolded, and each of the first pole lug area Z1, the second pole lug area Z2 and the third pole lug area Z3 includes at least two first sub-pole lugs 1111.
示例性地，第一极耳区Z1靠近第一主体区111a的内端E3，第三极耳区Z3靠近第一主体区111a的外端E4。Exemplarily, the first tab region Z1 is close to the inner end E3 of the first main body region 111 a , and the third tab region Z3 is close to the outer end E4 of the first main body region 111 a .
在一些实施例中，沿第一极片11展开后的长度方向X，第一极耳区Z1的相邻的第一子极耳1111之间的最小间距为d1，第二极耳区Z2的相邻的第一子极耳1111之间的最小间距为d2，第三极耳区Z3的相邻的第一子极耳1111之间的最小间距为d3，d1、d2和d3满足：d2＜d1，d2＜d3。电化学装置1000还包括容纳于壳体2内的集流盘4，集流盘4焊接于第二极耳区Z2。In some embodiments, along the length direction X after the first pole piece 11 is unfolded, the minimum spacing between adjacent first sub-pole tabs 1111 in the first pole tab region Z1 is d1, the minimum spacing between adjacent first sub-pole tabs 1111 in the second pole tab region Z2 is d2, and the minimum spacing between adjacent first sub-pole tabs 1111 in the third pole tab region Z3 is d3, and d1, d2 and d3 satisfy: d2＜d1, d2＜d3. The electrochemical device 1000 also includes a current collecting plate 4 accommodated in the housing 2, and the current collecting plate 4 is welded to the second pole tab region Z2.
示例性地，沿第一极片11展开后的长度方向X，第一极耳区Z1的第一子极耳1111与第二极耳区Z2的第一子极耳1111之间的最小间距可以根据需要灵活设置，例如，可以为d1。Exemplarily, along the length direction X after the first pole piece 11 is unfolded, the minimum distance between the first sub-pole lug 1111 in the first pole lug region Z1 and the first sub-pole lug 1111 in the second pole lug region Z2 can be flexibly set as needed, for example, can be d1.
示例性地，沿第一极片11展开后的长度方向X，第三极耳区Z3的第一子极耳1111与第二极耳区Z2的第一子极耳1111之间的最小间距可以根据需要灵活设置，例如，可以为d3。Exemplarily, along the length direction X after the first pole piece 11 is unfolded, the minimum distance between the first sub-pole lug 1111 in the third pole lug zone Z3 and the first sub-pole lug 1111 in the second pole lug zone Z2 can be flexibly set as needed, for example, can be d3.
第二极耳区Z2的相邻的第一子极耳1111之间的间距较小，在将第一空箔区111b揉平后，第二极耳区Z2更为致密，第二极耳区Z2与集流盘4的焊接强度更高，出现虚焊的风险更低。第一极耳区Z1和第三极耳区Z3无需与集流盘4焊接，第一极耳区Z1的第一子极耳1111之间可具有较大的间隙、第三极耳区Z3的第一子极耳1111之间可具有较大的间隙，这样可以便于电解液浸润电极组件1。The spacing between adjacent first sub-electrode tabs 1111 of the second pole tab region Z2 is small. After the first empty foil region 111b is flattened, the second pole tab region Z2 is more compact, and the welding strength between the second pole tab region Z2 and the current collector 4 is higher, and the risk of a cold weld is lower. The first pole tab region Z1 and the third pole tab region Z3 do not need to be welded to the current collector 4. There can be a larger gap between the first sub-electrode tabs 1111 of the first pole tab region Z1 and a larger gap between the first sub-electrode tabs 1111 of the third pole tab region Z3, which can facilitate the electrolyte to infiltrate the electrode assembly 1.
在一些实施例中，d1≤d3。第三极耳区Z3更靠近外圈，外圈的第一空箔区111b具有更大的周长，第三极耳区Z3的第一子极耳1111之间可具有更大的间隙。In some embodiments, d1≤d3. The third tab zone Z3 is closer to the outer ring, the first empty foil zone 111b of the outer ring has a larger circumference, and the first sub-tabs 1111 of the third tab zone Z3 may have a larger gap between them.
在一些实施例中，d2为0mm-20mm。可选地，d2为0mm、3mm、5mm、10mm、15mm或20mm。In some embodiments, d2 is 0 mm-20 mm. Optionally, d2 is 0 mm, 3 mm, 5 mm, 10 mm, 15 mm or 20 mm.
在一些实施例中，沿第一极片11展开后的长度方向X，第二极耳区Z2的尺寸为0.6m-1.1m，即第二极耳区Z2的多个第一子极耳1111的尺寸之和为0.6m-1.1m。In some embodiments, along the length direction X after the first pole piece 11 is unfolded, the size of the second pole lug region Z2 is 0.6m-1.1m, that is, the sum of the sizes of the plurality of first sub-pole lugs 1111 of the second pole lug region Z2 is 0.6m-1.1m.
本申请实施例可增大第二极耳区Z2与集流盘4的过流面积和连接强度。The embodiment of the present application can increase the flow area and connection strength between the second pole lug area Z2 and the current collecting plate 4.
在一些实施例中，参照图19，第一空箔区111b包括沿第一极片11展开后的长度方向X布置的第一极耳区Z1、第二极耳区Z2和第三极耳区Z3，第一极耳区Z1和第三极耳区Z3中的每一者均包括至少两个第一子极耳1111，第二极耳区Z2包括一个第一子极耳1111。沿第一极片11展开后的长度方向X，第二极耳区Z2的第一子极耳1111的尺寸大于第一极耳区Z1的第一子极耳1111的尺寸，第二极耳区Z2的第一子极耳1111的尺寸大于第三极耳区Z3的第一子极耳1111的尺寸。电化学装置1000还包括容纳于壳体2内的集流盘4，集流盘4焊接于第二极耳区Z2。In some embodiments, referring to FIG. 19 , the first empty foil area 111b includes a first pole lug area Z1, a second pole lug area Z2, and a third pole lug area Z3 arranged along the length direction X after the first pole piece 11 is unfolded, each of the first pole lug area Z1 and the third pole lug area Z3 includes at least two first sub-pole lugs 1111, and the second pole lug area Z2 includes one first sub-pole lug 1111. Along the length direction X after the first pole piece 11 is unfolded, the size of the first sub-pole lug 1111 of the second pole lug area Z2 is larger than the size of the first sub-pole lug 1111 of the first pole lug area Z1, and the size of the first sub-pole lug 1111 of the second pole lug area Z2 is larger than the size of the first sub-pole lug 1111 of the third pole lug area Z3. The electrochemical device 1000 also includes a current collecting plate 4 accommodated in the housing 2, and the current collecting plate 4 is welded to the second pole lug area Z2.
第二极耳区Z2的第一子极耳1111连续设置且具有较大的尺寸，在将第一空箔区111b揉平后，第二极耳区Z2更为致密，第二极耳区Z2与集流盘4的焊接强度更高，出现虚焊的风险更低。第一极耳区Z1和第三极耳区Z3无需与集流盘4焊接，第一极耳区Z1的第一子极耳1111之间可具有较大的间隙、第三极耳区Z3的第一子极耳1111之间可具有较大的间隙，这样可以便于电解液浸润电极组件。The first sub-electrode tabs 1111 of the second pole tab area Z2 are continuously arranged and have a larger size. After the first empty foil area 111b is flattened, the second pole tab area Z2 is more compact, and the welding strength between the second pole tab area Z2 and the current collecting plate 4 is higher, and the risk of a cold weld is lower. The first pole tab area Z1 and the third pole tab area Z3 do not need to be welded to the current collecting plate 4. There can be a larger gap between the first sub-electrode tabs 1111 of the first pole tab area Z1 and the first sub-electrode tabs 1111 of the third pole tab area Z3, which can facilitate the electrolyte to infiltrate the electrode assembly.
在一些实施例中，沿第一极片11展开后的长度方向X，第二极耳区Z2的第一子极耳1111的尺寸Kz为0.6m-1.1m。可选地，Kz为0.6m、0.7m、0.8m、0.9m、1.0m或1.1m。In some embodiments, along the length direction X after the first pole piece 11 is unfolded, the size Kz of the first sub-pole lug 1111 of the second pole lug region Z2 is 0.6m-1.1m. Optionally, Kz is 0.6m, 0.7m, 0.8m, 0.9m, 1.0m or 1.1m.
示例性地，Kz可为第二极耳区Z2的第一子极耳1111沿第一极片展开后的长度方向X的最小尺寸。Exemplarily, Kz may be the minimum dimension of the first sub-pole tab 1111 of the second pole tab region Z2 along the length direction X after the first pole piece is unfolded.
本申请实施例可增大第二极耳区Z2与集流盘4的过流面积和连接强度。The embodiment of the present application can increase the flow area and connection strength between the second pole lug area Z2 and the current collecting plate 4.
在一些实施例中，第二极耳区Z2的第一子极耳1111的尺寸Kz大于第一极耳区Z1的多个第一子极耳1111的尺寸总和。In some embodiments, a size Kz of the first sub-tab 1111 of the second tab zone Z2 is greater than the sum of sizes of the plurality of first sub-tabs 1111 of the first tab zone Z1 .
在一些实施例中，第二极耳区Z2的第一子极耳1111的尺寸Kz大于第三极耳区Z3的多个第一子极耳1111的尺寸总和。In some embodiments, a size Kz of the first sub-tab 1111 of the second tab zone Z2 is greater than the sum of sizes of the plurality of first sub-tabs 1111 of the third tab zone Z3 .
参照图20和图21，在一些实施例中，第二极片12包括第二集流体121和设置于第二集流体121的第二活性物质122。20 and 21 , in some embodiments, the second pole piece 12 includes a second current collector 121 and a second active material 122 disposed on the second current collector 121 .
示例性地，第二集流体121可具有在其自身厚度方向相对的两个表面，第二活性物质122可设置在第二集流体121相对的两个表面的任意一者或两者上。For example, the second current collector 121 may have two surfaces opposite to each other in its thickness direction, and the second active material 122 may be disposed on any one or both of the two opposite surfaces of the second current collector 121 .
在一些实施例中，第二集流体121可采用金属箔片，例如不锈钢箔、铜箔、铝箔、镍箔等。In some embodiments, the second current collector 121 may be made of metal foil, such as stainless steel foil, copper foil, aluminum foil, nickel foil, etc.
在一些实施例中，第二集流体121包括第二主体区121a和第二空箔区121b，第二活性物质122设于第二主体区121a。第二主体区121a和第二空箔区121b的布置方向垂直于卷绕方向V。In some embodiments, the second current collector 121 includes a second main region 121a and a second empty foil region 121b, and the second active material 122 is disposed in the second main region 121a. The second main region 121a and the second empty foil region 121b are arranged in a direction perpendicular to the winding direction V.
第二主体区121a的至少一个表面涂覆有第二活性物质122。第二空箔区121b的两个表面均未涂覆第二活性物质122。At least one surface of the second main body region 121a is coated with the second active material 122. The second active material 122 is not coated on both surfaces of the second empty foil region 121b.
第二空箔区121b的部分区域可以设有其它不包括活性材料的涂层，比如绝缘涂层。当然，第二空箔区121b的至少部分区域的两个表面均是裸露地、未被其它涂层覆盖的。第二空箔区121b的裸露区域可以作为电极组件1的第二极耳10b，第二极耳10b可以将电极组件1的电流导出。Part of the second empty foil area 121b may be provided with other coatings that do not include active materials, such as insulating coatings. Of course, both surfaces of at least part of the second empty foil area 121b are exposed and not covered by other coatings. The exposed area of the second empty foil area 121b can serve as the second pole tab 10b of the electrode assembly 1, and the second pole tab 10b can lead the current of the electrode assembly 1.
示例性地，第二主体区121a和第二空箔区121b的布置方向平行于第二极片12展开后的宽度方向Y＇。Exemplarily, the arrangement direction of the second main body region 121 a and the second hollow foil region 121 b is parallel to the width direction Y′ of the second pole piece 12 after it is unfolded.
在一些实施例中，第二空箔区121b远离第二主体区121a的部分通过揉平形成第二揉平区。In some embodiments, the portion of the second hollow foil region 121 b away from the second main body region 121 a is flattened to form a second flattened region.
在电极组件1卷绕完成后，第二空箔区121b卷绕并大体形成柱状结构，外部工装可沿着柱状结构的周向对第二空箔区121b施加外力，使第二空箔区121b发生弯折变形，从而使第二空箔区121b沿径向相邻的两层更紧凑，并形成第二揉平区。After the electrode assembly 1 is wound, the second empty foil area 121b is wound and roughly forms a columnar structure. The external tooling can apply external force to the second empty foil area 121b along the circumference of the columnar structure to bend and deform the second empty foil area 121b, thereby making the two radially adjacent layers of the second empty foil area 121b more compact and forming a second flattened area.
第二揉平区形成致密的端面，从而便于与其它导电结构连接，比如，与集流盘4或壳体2焊接。The second flattened area forms a dense end surface, so as to facilitate connection with other conductive structures, such as welding with the collecting plate 4 or the housing 2 .
在一些实施例中，第二极片12为负极极片，对应地，第二集流体121为负极集流体，第二活性物质122为负极活性物质。In some embodiments, the second electrode sheet 12 is a negative electrode sheet, and correspondingly, the second current collector 121 is a negative electrode current collector, and the second active material 122 is a negative electrode active material.
参照图22，本申请还提供了一种电池包3000，其包括前述任一实施例提供的电化学装置1000。22 , the present application further provides a battery pack 3000 , which includes the electrochemical device 1000 provided in any of the aforementioned embodiments.
在一些实施例中，电池包3000包括一个电池模组2000或并联设置的多个电池模组2000，一个电池模组2000包括串联设置的多个电化学装置1000。In some embodiments, the battery pack 3000 includes one battery module 2000 or a plurality of battery modules 2000 arranged in parallel, and one battery module 2000 includes a plurality of electrochemical devices 1000 arranged in series.
多个电化学装置1000串联，可以提升电池包的输出电压。Connecting multiple electrochemical devices 1000 in series can increase the output voltage of the battery pack.
示例性地，电池包3000的电池模组2000的数量可为1、2、3、4、5、6、7、8、9或10。For example, the number of battery modules 2000 of the battery pack 3000 may be 1, 2, 3, 4, 5, 6, 7, 8, 9 or 10.
一个电池模组2000包括的电化学装置1000的数量可为1、2、3、4、5、6、7、8、9或10。The number of electrochemical devices 1000 included in a battery module 2000 may be 1, 2, 3, 4, 5, 6, 7, 8, 9 or 10.
在一些实施例中，一个电池模组2000包括5个电化学装置1000或6个电化学装置1000。In some embodiments, one battery module 2000 includes five electrochemical devices 1000 or six electrochemical devices 1000 .
在一些实施例中，电池模组2000的数量为2或3。In some embodiments, the number of battery modules 2000 is 2 or 3.
在一些实施例中，电池包还包括箱体2100，电池模组2000容纳于箱体2100内。In some embodiments, the battery pack further includes a box body 2100 , and the battery module 2000 is accommodated in the box body 2100 .
参照图23，本申请还提供了一种用电设备4000，其包括前述任一实施例提供的电池包3000。电池包3000可以为用电设备4000的工作提供电能。23 , the present application further provides an electric device 4000, which includes the battery pack 3000 provided in any of the above embodiments. The battery pack 3000 can provide electric energy for the operation of the electric device 4000.
本申请实施例的用电设备4000可以是便携式设备、笔记本电脑、电动玩具、无人机、电动工具、储能系统等等。电动工具包括金属切削电动工具、清洁工具等，例如，电钻、电动扳手、吸尘器、扫地机器人等等。本申请实施例对上述用电设备不做特殊限制。The electric device 4000 in the embodiment of the present application may be a portable device, a laptop computer, an electric toy, a drone, an electric tool, an energy storage system, etc. The electric tool includes a metal cutting electric tool, a cleaning tool, etc., for example, an electric drill, an electric wrench, a vacuum cleaner, a sweeping robot, etc. The embodiment of the present application does not impose any special restrictions on the above-mentioned electric devices.
在一些实施例中，本申请实施例提供了一种电化学装置，其包括壳体和容纳于壳体内的电极组件。In some embodiments, embodiments of the present application provide an electrochemical device, which includes a housing and an electrode assembly accommodated in the housing.
电极组件包括正极极片、负极极片和隔膜，隔膜将正极极片和负极极片绝缘隔离。The electrode assembly includes a positive electrode sheet, a negative electrode sheet and a separator, and the separator insulates the positive electrode sheet and the negative electrode sheet.
实施例1Example 1
电化学装置的制作。Fabrication of electrochemical devices .
<正极极片的制作><Production of positive electrode sheet>
将镍钴锰酸锂Ni91(LiNi0.91Co0.04Mn0.05O2)、聚偏二氟乙烯(PVDF，重均分子量为7×106)、导电炭黑按照质量比95.8:2.8:1.4进行混合，加入N-甲基吡咯烷酮(NMP)作为溶剂，在真空搅拌机作用下搅拌均匀，得到固含量为75wt％且体系均匀的正极浆料。将正极浆料均匀涂布在厚度为13μm的正极集流体铝箔的一个表面上，90℃条件下烘干，得到单面涂布正极活性物质的正极极片(正极极片单侧的正极活性物质的单位面积涂布重量为217mg/1540.25mm2)。之后，在该铝箔的另一个表面上重复以上步骤，即得到双面涂布正极活性物质的正极极片。再经冷压、裁片得到正极极片待用。Lithium nickel cobalt manganese oxide Ni91 (LiNi0.91 Co0.04 Mn0.05 O2 ), polyvinylidene fluoride (PVDF, weight average molecular weight of 7×106 ), and conductive carbon black are mixed in a mass ratio of 95.8:2.8:1.4, and N-methylpyrrolidone (NMP) is added as a solvent. The mixture is stirred evenly under the action of a vacuum mixer to obtain a positive electrode slurry with a solid content of 75wt% and a uniform system. The positive electrode slurry is evenly coated on one surface of a positive electrode current collector aluminum foil with a thickness of 13μm, and dried at 90°C to obtain a positive electrode sheet with a single-sided coating of positive electrode active material (the unit area coating weight of the positive electrode active material on one side of the positive electrode sheet is 217mg/1540.25mm2 ). Thereafter, the above steps are repeated on the other surface of the aluminum foil to obtain a positive electrode sheet with a double-sided coating of positive electrode active material. The positive electrode sheet is then cold pressed and cut into pieces to be used.
示例性地，参照图6和图7，正极极片采用与第一极片类似的结构。具体地，L1＝L2＝1.36m。W2为63.2mm，W1为4mm，W4为3.2mm。6 and 7 , the positive electrode sheet adopts a structure similar to that of the first electrode sheet. Specifically, L1=L2=1.36 mm. W2 is 63.2 mm, W1 is 4 mm, and W4 is 3.2 mm.
<负极极片的制备><Preparation of negative electrode sheet>
将人造石墨、导电炭黑、丁苯橡胶(SBR，重均分子量为5×106)按照质量比97.4:1.4:1.2进行混合，然后加入去离子水作为溶剂，在真空搅拌机作用下搅拌均匀，得到固含量为51wt％且体系均匀的负极浆料。将负极浆料均匀涂覆在厚度为8μm的负极集流体铜箔的一个表面上，90℃条件下烘干，得到单面涂布负极活性材料层的负极极片(负极极片单侧的负极活性物质的单位面积涂布重量为113mg/1540.25mm2)。之后，在该铜箔的另一个表面上重复以上步骤，得到双面涂布负极活性材料层的负极极片。再经冷压、裁片得到负极极片待用。Artificial graphite, conductive carbon black, and styrene-butadiene rubber (SBR, weight average molecular weight of 5×106 ) were mixed in a mass ratio of 97.4:1.4:1.2, and then deionized water was added as a solvent, and the mixture was stirred evenly under the action of a vacuum mixer to obtain a negative electrode slurry with a solid content of 51wt% and a uniform system. The negative electrode slurry was evenly coated on one surface of a negative electrode current collector copper foil with a thickness of 8μm, and dried at 90°C to obtain a negative electrode sheet coated with a negative electrode active material layer on one side (the unit area coating weight of the negative electrode active material on one side of the negative electrode sheet was 113mg/1540.25mm2 ). After that, the above steps were repeated on the other surface of the copper foil to obtain a negative electrode sheet coated with a negative electrode active material layer on both sides. The negative electrode sheet was then cold pressed and cut into pieces for standby use.
示例性地，参照图6和图7，负极极片采用与第一极片类似的结构。具体地，L1＝L2＝1.464m。W2为64.1mm，W1为4mm，W4为3.2mm。6 and 7 , the negative electrode plate adopts a structure similar to that of the first electrode plate. Specifically, L1=L2=1.464 mm. W2 is 64.1 mm, W1 is 4 mm, and W4 is 3.2 mm.
<隔膜的制备><Preparation of Separator>
将氧化铝涂层设置于基膜的一个表面上，以制备出隔膜。其中，基膜选用厚度9μm的聚乙烯基膜，氧化铝涂层的厚度为2μm。The aluminum oxide coating is disposed on one surface of the base film to prepare a diaphragm, wherein the base film is a polyethylene base film with a thickness of 9 μm, and the thickness of the aluminum oxide coating is 2 μm.
<电解液的制备><Preparation of Electrolyte>
在含水量小于10ppm的环境下，将碳酸乙烯酯(EC)、碳酸甲乙酯(EMC)按照质量比70:30混合得到非水有机溶剂，然后向非水有机溶剂中加入六氟磷酸锂(LiPF6)和添加剂氟代碳酸乙烯酯(FEC)溶解并混合均匀，得到电解液。其中，基于电解液的质量，LiPF6的质量百分含量为15％，氟代碳酸乙烯酯的质量百分含量为1％，余量为非水有机溶剂。In an environment with a water content of less than 10 ppm, ethylene carbonate (EC) and ethyl methyl carbonate (EMC) are mixed at a mass ratio of 70:30 to obtain a non-aqueous organic solvent, and then lithium hexafluorophosphate (LiPF6 ) and an additive fluoroethylene carbonate (FEC) are added to the non-aqueous organic solvent to dissolve and mix uniformly to obtain an electrolyte. Based on the mass of the electrolyte, the mass percentage of LiPF6 is 15%, the mass percentage of fluoroethylene carbonate is 1%, and the balance is the non-aqueous organic solvent.
<电化学装置的制备><Preparation of electrochemical device>
将上述制备得到的负极极片、隔膜以及正极极片按顺序堆叠卷绕得到具有卷绕结构的电极组件。将电极组件安装到铝壳内，经过辊边、注液、化成、脱气、整形等工艺流程得到电化学装置,电化学装置为直径为21mm的21700锂离子电芯。化成过程具体为：在25℃，将电化学装置以0.02C恒流充电至3.3V，再以0.1C恒流充电至3.6V。The negative electrode sheet, separator and positive electrode sheet prepared above are stacked and wound in sequence to obtain an electrode assembly with a winding structure. The electrode assembly is installed in an aluminum shell, and an electrochemical device is obtained through rolling, liquid injection, formation, degassing, shaping and other process flows. The electrochemical device is a 21700 lithium-ion battery cell with a diameter of 21mm. The formation process is as follows: at 25°C, the electrochemical device is charged to 3.3V at a constant current of 0.02C, and then charged to 3.6V at a constant current of 0.1C.
按照上述方法，制备出电化学装置。According to the above method, an electrochemical device was prepared.
电化学装置测试方法Electrochemical Device Test Methods
按照下述步骤对电化学装置进行测试，测试过程采用电池测试仪(Neware CT-4016-5V-100A)测试。Follow the steps below to test the electrochemical device using a battery tester (Neware CT-4016-5V-100A).
(一)在25℃恒温箱(科明EH-1000)内静置2小时，将电化学装置充电至100％SOC。具体地，在25℃恒温下，电化学装置以0.5C恒流放电至该电化学装置的放电截止电压(2.5V)，然后以0.5C恒流充电至该电化学装置的充电截止电压(4.2V)，然后以充电截止电压恒压充电至0.05C，此时该电化学装置处于100％的SOC。(i) The electrochemical device was placed in a 25°C thermostat (Coming EH-1000) for 2 hours to charge the electrochemical device to 100% SOC. Specifically, at a constant temperature of 25°C, the electrochemical device was discharged at a constant current of 0.5C to the discharge cut-off voltage (2.5V) of the electrochemical device, then charged at a constant current of 0.5C to the charge cut-off voltage (4.2V) of the electrochemical device, and then charged at a constant voltage of the charge cut-off voltage to 0.05C, at which time the electrochemical device was at 100% SOC.
(二)在25℃恒温箱(科明EH-1000)内静置2小时，将处于100％SOC的电化学装置以0.2C恒流放电至该电化学装置的放电截止电压(2.5V)，测试放电容量，即为电化学装置的额定容量，再以0.5C恒流充电至该电化学装置的充电截止电压(4.2V)，然后以充电截止电压恒压充电至0.05C，此时该电化学装置处于100％的SOC。(ii) After standing in a 25°C constant temperature box (Coming EH-1000) for 2 hours, the electrochemical device at 100% SOC was discharged at a constant current of 0.2C to the discharge cut-off voltage (2.5V) of the electrochemical device, and the discharge capacity was tested, which was the rated capacity of the electrochemical device. Then, the electrochemical device was charged at a constant current of 0.5C to the charge cut-off voltage (4.2V) of the electrochemical device, and then charged at a constant voltage of the charge cut-off voltage to 0.05C, at which time the electrochemical device was at 100% SOC.
(三)将上述处于100％SOC的电化学装置放置到25℃恒温箱(科明EH-1000)内静置2小时，然后在该温度下以与0.1C倍率对应的电流i 1放电10s，测得电压V1；然后再以与1C倍率对应的电流i2放电1s，并测得电压V2；电化学装置的直流电阻为(V1-V2)/(i2-i1)。(III) The electrochemical device at 100% SOC was placed in a 25°C thermostat (Comin EH-1000) for 2 hours, and then discharged at this temperature with a current i 1 corresponding to a 0.1C rate for 10 seconds, and the voltage V1 was measured; then, the device was discharged with a current i2 corresponding to a 1C rate for 1 second, and the voltage V2 was measured; the DC resistance of the electrochemical device was (V1-V2)/(i2-i1).
(四)将上述测试完直流电阻的电化学装置在25℃恒温箱(科明EH-1000)内静置2小时，然后以0.5C恒流放电至该电化学装置的放电截止电压(2.5V)，然后以0.5C恒流充电至该电化学装置的充电截止电压(4.2V)，然后以充电截止电压恒压充电至0.05C，此时该电化学装置处于100％的SOC。(IV) The electrochemical device after the DC resistance test was placed in a 25°C constant temperature box (Coming EH-1000) for 2 hours, then discharged at a constant current of 0.5C to the discharge cut-off voltage (2.5V) of the electrochemical device, then charged at a constant current of 0.5C to the charge cut-off voltage (4.2V) of the electrochemical device, and then charged at a constant voltage of the charge cut-off voltage to 0.05C, at which time the electrochemical device was at 100% SOC.
(五)将上述处于100％SOC的电化学装置25℃恒温箱(科明EH-1000)内静置2小时。然后，保持恒温箱内的温度，并以5C的放电倍率对电化学装置进行放电，直至电化学装置放电至放电截止电压(2.5V)。在放电的过程中，记录该电化学装置的放电参数。(V) The electrochemical device at 100% SOC was placed in a 25°C thermostat (Coming EH-1000) for 2 hours. Then, the temperature in the thermostat was maintained and the electrochemical device was discharged at a discharge rate of 5C until the electrochemical device was discharged to the discharge cut-off voltage (2.5V). During the discharge process, the discharge parameters of the electrochemical device were recorded.
(六)将结束了步骤(五)的电化学装置在25℃恒温箱(科明EH-1000)内静置2小时，然后以0.5C恒流充电至该电化学装置的充电截止电压(4.2V)，然后以充电截止电压恒压充电至0.05C，此时该电化学装置处于100％的SOC。(vi) The electrochemical device that has completed step (v) is placed in a 25°C constant temperature box (Comin EH-1000) for 2 hours, then charged at a constant current of 0.5C to the charge cutoff voltage (4.2V) of the electrochemical device, and then charged at a constant voltage of the charge cutoff voltage to 0.05C, at which time the electrochemical device is at 100% SOC.
(七)重复步骤(五)和步骤(六)，并改变步骤(五)中的放电倍率，记录电化学装置的放电参数。(VII) Repeat steps (V) and (VI), and change the discharge rate in step (V), and record the discharge parameters of the electrochemical device.
其中，电化学装置的环境温度、放电倍率及其对应的放电容量、额定容量、直流电阻等参数如表1。Among them, the ambient temperature, discharge rate and its corresponding discharge capacity, rated capacity, DC resistance and other parameters of the electrochemical device are shown in Table 1.
表1
Table 1
参照表1、图24和图25，实施例1的电化学装置在以15C-20C的高倍率进行放电时能量损耗较低，电化学装置的放电容量与电化学装置的额定容量之比大于或等于99％，可以为用电设备提供更多的电能。电化学装置在以15C的高倍率进行放电时，能够使放电容量达到甚至超过额定容量。Referring to Table 1, FIG. 24 and FIG. 25, the electrochemical device of Example 1 has low energy loss when discharging at a high rate of 15C-20C, and the ratio of the discharge capacity of the electrochemical device to the rated capacity of the electrochemical device is greater than or equal to 99%, which can provide more electric energy for electrical equipment. When the electrochemical device is discharged at a high rate of 15C, the discharge capacity can reach or even exceed the rated capacity.
实施例1的电化学装置的内阻仅为6毫欧(mΩ)，其在以15C-20C的高倍率放电过程中的能量损耗较小，从而提升电化学装置的放电容量，改善电化学装置的放电性能。The internal resistance of the electrochemical device of Example 1 is only 6 milliohms (mΩ), and the energy loss during the high rate discharge process of 15C-20C is small, thereby increasing the discharge capacity of the electrochemical device and improving the discharge performance of the electrochemical device.
实施例2Example 2
实施例2的电化学装置的制作方法与实施例1的电化学装置的制作方法的不同之处在于：实施例2的正极极片的正极活性材料采用LiNi0.8Co0.1Mn0.1O2。The difference between the manufacturing method of the electrochemical device of Example 2 and the manufacturing method of the electrochemical device of Example 1 is that the positive electrode active material of the positive electrode sheet of Example 2 is LiNi0.8 Co0.1 Mn0.1 O2 .
实施例2的电化学装置测试方法与实施例1的电化学装置测试方法相同。The electrochemical device testing method of Example 2 is the same as the electrochemical device testing method of Example 1.
实施例2的电化学装置的环境温度、放电倍率及其对应的放电容量、额定容量、直流电阻等参数如表2。The ambient temperature, discharge rate and corresponding discharge capacity, rated capacity, DC resistance and other parameters of the electrochemical device of Example 2 are shown in Table 2.
表2
Table 2
参照表2，实施例2的电化学装置在以15C-20C的高倍率进行放电时能量损耗较低，电化学装置的放电容量与电化学装置的额定容量之比大于或等于99％，可以为用电设备提供更多的电能。Referring to Table 2, the electrochemical device of Example 2 has low energy loss when discharged at a high rate of 15C-20C, and the ratio of the discharge capacity of the electrochemical device to the rated capacity of the electrochemical device is greater than or equal to 99%, which can provide more electrical energy for electrical equipment.
实施例3Example 3
实施例3的电化学装置的制作方法与实施例1的电化学装置的制作方法的不同之处在于：实施例3的正极极片的正极活性材料采用LiNi0.95Co0.01Mn0.04O2。The difference between the manufacturing method of the electrochemical device of Example 3 and the manufacturing method of the electrochemical device of Example 1 is that the positive electrode active material of the positive electrode sheet of Example 3 is LiNi0.95 Co0.01 Mn0.04 O2 .
实施例3的电化学装置测试方法与实施例1的电化学装置测试方法相同。The electrochemical device testing method of Example 3 is the same as the electrochemical device testing method of Example 1.
实施例3的电化学装置的环境温度、放电倍率及其对应的放电容量、额定容量、直流电阻等参数如表3。The ambient temperature, discharge rate and corresponding discharge capacity, rated capacity, DC resistance and other parameters of the electrochemical device of Example 3 are shown in Table 3.
表3
Table 3
参照表3，实施例3的电化学装置在以15C-20C的高倍率进行放电时能量损耗较低，电化学装置的放电容量与电化学装置的额定容量之比大于或等于99％，可以为用电设备提供更多的电能。Referring to Table 3, the electrochemical device of Example 3 has low energy loss when discharged at a high rate of 15C-20C, and the ratio of the discharge capacity of the electrochemical device to the rated capacity of the electrochemical device is greater than or equal to 99%, which can provide more electrical energy for electrical equipment.
实施例4Example 4
电化学装置的制作。Fabrication of electrochemical devices .
<正极极片的制作><Production of positive electrode sheet>
与实施例1的区别在于，正极极片采用图10和图11所示的第一极片的结构。具体地，参照图10和图11，L1＝L2＝1.36m，W2为63.2mm，W1为4mm，W4为3.2mm。第一空箔区沿卷绕方向的外端和内端的角部均设有相同的三角切口，其中，La＝W1＝4mm,W3＝0.5W1＝2mm。The difference from Example 1 is that the positive electrode sheet adopts the structure of the first electrode sheet shown in Figures 10 and 11. Specifically, referring to Figures 10 and 11, L1 = L2 = 1.36m, W2 is 63.2mm, W1 is 4mm, and W4 is 3.2mm. The corners of the outer end and the inner end of the first empty foil area along the winding direction are both provided with the same triangular cutout, wherein La = W1 = 4mm, W3 = 0.5W1 = 2mm.
<负极极片的制备><Preparation of negative electrode sheet>
与实施例1的区别在于，负极极片采用图10和图11所示的第一极片的结构。参照图10和图11，L1＝L2＝1.464m，W2为64.1mm，W1为4mm，W4为3.2mm。第一空箔区沿卷绕方向的外端和内端的角部均设有相同的三角切口，其中，La＝W1＝4mm,W3＝0.5W1＝2mm。负极极片的切口与正极极片的切口形状、大小相同。The difference from Example 1 is that the negative electrode sheet adopts the structure of the first electrode sheet shown in Figures 10 and 11. Referring to Figures 10 and 11, L1 = L2 = 1.464m, W2 is 64.1mm, W1 is 4mm, and W4 is 3.2mm. The corners of the outer and inner ends of the first empty foil area along the winding direction are provided with the same triangular cutouts, wherein La = W1 = 4mm, W3 = 0.5W1 = 2mm. The cutout of the negative electrode sheet is the same in shape and size as the cutout of the positive electrode sheet.
<隔膜的制备><Preparation of Separator>
与实施例1相同。Same as Example 1.
<电解液的制备><Preparation of Electrolyte>
与实施例1相同。Same as Example 1.
<电化学装置的制备><Preparation of electrochemical device>
与实施例1相同。Same as Example 1.
按照上述方法，制备出电化学装置。According to the above method, an electrochemical device was prepared.
实施例4的电化学装置测试方法与实施例1的电化学装置测试方法相同。The electrochemical device testing method of Example 4 is the same as the electrochemical device testing method of Example 1.
实施例4的电化学装置的环境温度、放电倍率及其对应的放电容量、额定容量、直流电阻等参数如表4。The ambient temperature, discharge rate and corresponding discharge capacity, rated capacity, DC resistance and other parameters of the electrochemical device of Example 4 are shown in Table 4.
表4
Table 4
参照表4，实施例4的电化学装置在以15C-20C的高倍率进行放电时能量损耗较低，电化学装置的放电容量与电化学装置的额定容量之比大于或等于99％，可以为用电设备提供更多的电能。Referring to Table 4, the electrochemical device of Example 4 has low energy loss when discharged at a high rate of 15C-20C, and the ratio of the discharge capacity of the electrochemical device to the rated capacity of the electrochemical device is greater than or equal to 99%, which can provide more electrical energy for electrical equipment.
实施例5Example 5
电化学装置的制作。Fabrication of electrochemical devices .
<正极极片的制作><Production of positive electrode sheet>
与实施例1的区别在于，正极极片采用图14所示的第一极片的结构。具体地，参照图14，L2＝1.36m。第一极片共包括10个第一子极耳，10个第一子极耳的尺寸相同，10个第一子极耳的总长L3(K1+K2+……+K10)为1.1m，相邻两个第一子极耳间距相等，D为20mm，沿第一极片展开后的长度方向，第一空箔区的内端和第一主体区的内端间隔距离D1为40mm，第一空箔区的外端和第一主体区的外端间隔第二距离D2为40mm。W2为63.2mm，W1为4mm，W4为3.2mm。The difference from Example 1 is that the positive electrode plate adopts the structure of the first electrode plate shown in Figure 14. Specifically, referring to Figure 14, L2 = 1.36m. The first electrode plate includes 10 first sub-electrode ears, and the 10 first sub-electrode ears have the same size. The total length L3 (K1+K2+...+K10) of the 10 first sub-electrode ears is 1.1m. The distance between two adjacent first sub-electrode ears is equal, D is 20mm, and along the length direction of the first electrode plate after unfolding, the inner end of the first empty foil area and the inner end of the first main body area are separated by a distance D1 of 40mm, and the outer end of the first empty foil area and the outer end of the first main body area are separated by a second distance D2 of 40mm. W2 is 63.2mm, W1 is 4mm, and W4 is 3.2mm.
<负极极片的制备><Preparation of negative electrode sheet>
与实施例1的区别在于，负极极片采用图14所示的第一极片的结构。参照图14，L2为1.464m。第一极片共包括10个第一子极耳，10个第一子极耳的尺寸相同，10个第一子极耳的总长L3(K1+K2+……+K10)为1.2m；相邻两个第一子极耳间距相等，D为20mm，沿第一极片展开后的长度方向，第一空箔区的内端和第一主体区的内端间隔第一距离D1为42mm，第一空箔区的外端和第一主体区的外端间隔第二距离D2为42mm。W2为64.1mm，W1为4mm，W4为3.2mm。The difference from Example 1 is that the negative electrode plate adopts the structure of the first electrode plate shown in Figure 14. Referring to Figure 14, L2 is 1.464m. The first electrode plate includes 10 first sub-pole ears, and the 10 first sub-pole ears have the same size. The total length L3 (K1+K2+...+K10) of the 10 first sub-pole ears is 1.2m; the distance between two adjacent first sub-pole ears is equal, D is 20mm, and along the length direction of the first electrode plate after unfolding, the inner end of the first empty foil area and the inner end of the first main body area are separated by a first distance D1 of 42mm, and the outer end of the first empty foil area and the outer end of the first main body area are separated by a second distance D2 of 42mm. W2 is 64.1mm, W1 is 4mm, and W4 is 3.2mm.
<隔膜的制备><Preparation of Separator>
与实施例1相同。Same as Example 1.
<电解液的制备><Preparation of Electrolyte>
与实施例1相同。Same as Example 1.
<电化学装置的制备><Preparation of electrochemical device>
与实施例1相同。Same as Example 1.
按照上述方法，制备出电化学装置。According to the above method, an electrochemical device was prepared.
实施例5的电化学装置测试方法与实施例1的电化学装置测试方法相同。The electrochemical device testing method of Example 5 is the same as the electrochemical device testing method of Example 1.
实施例5的电化学装置的环境温度、放电倍率及其对应的放电容量、额定容量、直流电阻等参数如表5。The ambient temperature, discharge rate and corresponding discharge capacity, rated capacity, DC resistance and other parameters of the electrochemical device of Example 5 are shown in Table 5.
表5
Table 5
参照表5，实施例5的电化学装置在以15C-20C的高倍率进行放电时能量损耗较低，电化学装置的放电容量与电化学装置的额定容量之比大于或等于99％，可以为用电设备提供更多的电能。Referring to Table 5, the electrochemical device of Example 5 has low energy loss when discharged at a high rate of 15C-20C, and the ratio of the discharge capacity of the electrochemical device to the rated capacity of the electrochemical device is greater than or equal to 99%, which can provide more electrical energy for electrical equipment.
对比例1Comparative Example 1
INR21700-40T(21700电芯)INR21700-40T (21700 battery cell)
对比例1的INR21700-40T电芯的测试方法与实施例1的电化学装置测试方法相同。The test method of the INR21700-40T battery cell of Comparative Example 1 is the same as the test method of the electrochemical device of Example 1.
对比例1的INR21700-40T电芯的环境温度、放电倍率及其对应的放电容量、额定容量、直流电阻等参数如表6。The ambient temperature, discharge rate and corresponding discharge capacity, rated capacity, DC resistance and other parameters of the INR21700-40T battery cell of Comparative Example 1 are shown in Table 6.
表6
Table 6
参照表1至表6，相较于INR21700-40T电芯，实施例1-5的电化学装置，在以15C-20C的高倍率进行放电时能量损耗较低，具有更高的放电容量。Referring to Tables 1 to 6, compared with the INR21700-40T battery cell, the electrochemical devices of Examples 1 to 5 have lower energy loss and higher discharge capacity when discharged at a high rate of 15C-20C.
参照表6，INR21700-40T电芯在以20C的倍率放电时，电芯的电流切断装置(CID)启动并断开放电电路，INR21700-40T电芯仅能释放出部分容量。示例性地，电池测试仪(Neware CT-4016-5V-100A)可以测出从100％SOC到CID启动时放出的容量，即表6中的2643mAh。Referring to Table 6, when the INR21700-40T battery cell is discharged at a rate of 20C, the current cut-off device (CID) of the battery cell is activated and disconnects the discharge circuit, and the INR21700-40T battery cell can only release part of its capacity. For example, the battery tester (Neware CT-4016-5V-100A) can measure the capacity released from 100% SOC to the time when the CID is activated, which is 2643mAh in Table 6.
参照表6，INR21700-40T电芯在以15C-20C的倍率放电时，电芯内部温度较高，对电解液性能影响较大，影响放电性能和放电容量。Referring to Table 6, when the INR21700-40T battery cell is discharged at a rate of 15C-20C, the internal temperature of the battery cell is relatively high, which has a greater impact on the performance of the electrolyte, affecting the discharge performance and discharge capacity.
实施例6Example 6
电化学装置的制作。Fabrication of electrochemical devices .
<正极极片的制作><Production of positive electrode sheet>
将镍钴锰酸锂Ni91(LiNi0.91Co0.04Mn0.05O2)、聚偏二氟乙烯(PVDF，重均分子量为7×106)、导电炭黑按照质量比96:2:2进行混合，加入N-甲基吡咯烷酮(NMP)作为溶剂，在真空搅拌机作用下搅拌均匀，得到固含量为75wt％且体系均匀的正极浆料。将正极浆料均匀涂布在厚度为12μm的正极集流体铝箔的一个表面上，90℃条件下烘干，得到单面涂布正极活性物质的正极极片(正极极片单侧的正极活性物质的单位面积涂布重量为198mg/1540.25mm2)。之后，在该铝箔的另一个表面上重复以上步骤，即得到双面涂布正极活性物质的正极极片。再经冷压、裁片得到正极极片待用。Lithium nickel cobalt manganese oxide Ni91 (LiNi0.91 Co0.04 Mn0.05 O2 ), polyvinylidene fluoride (PVDF, weight average molecular weight of 7×106 ), and conductive carbon black are mixed in a mass ratio of 96:2:2, and N-methylpyrrolidone (NMP) is added as a solvent. The mixture is stirred evenly under the action of a vacuum mixer to obtain a positive electrode slurry with a solid content of 75wt% and a uniform system. The positive electrode slurry is evenly coated on one surface of a positive electrode current collector aluminum foil with a thickness of 12μm, and dried at 90°C to obtain a positive electrode sheet coated with a single-sided positive electrode active material (the unit area coating weight of the positive electrode active material on one side of the positive electrode sheet is 198mg/1540.25mm2 ). Thereafter, the above steps are repeated on the other surface of the aluminum foil to obtain a positive electrode sheet coated with a double-sided positive electrode active material. The positive electrode sheet is then cold pressed and cut into pieces to be used.
示例性地，参照图6和图7，正极极片采用与第一极片类似的结构。具体地，L1＝L2＝0.92m。W2为59mm，W1为4mm，W4为3.2mm。6 and 7 , the positive electrode sheet adopts a structure similar to that of the first electrode sheet. Specifically, L1=L2=0.92 mm, W2 is 59 mm, W1 is 4 mm, and W4 is 3.2 mm.
<负极极片的制备><Preparation of negative electrode sheet>
将人造石墨、导电炭黑、丁苯橡胶(SBR，重均分子量为5×106)按照质量比97.5:1.3:1.2进行混合，然后加入去离子水作为溶剂，在真空搅拌机作用下搅拌均匀，得到固含量为51wt％且体系均匀的负极浆料。将负极浆料均匀涂覆在厚度为8μm的负极集流体铜箔的一个表面上，90℃条件下烘干，得到单面涂布负极活性材料层的负极极片(负极极片单侧的负极活性物质的单位面积涂布重量为103mg/1540.25mm2)。之后，在该铜箔的另一个表面上重复以上步骤，得到双面涂布负极活性材料层的负极极片。再经冷压、裁片得到负极极片待用。Artificial graphite, conductive carbon black, and styrene-butadiene rubber (SBR, weight average molecular weight of 5×106 ) were mixed in a mass ratio of 97.5:1.3:1.2, and then deionized water was added as a solvent, and the mixture was stirred evenly under the action of a vacuum mixer to obtain a negative electrode slurry with a solid content of 51wt% and a uniform system. The negative electrode slurry was evenly coated on one surface of a negative electrode current collector copper foil with a thickness of 8μm, and dried at 90°C to obtain a negative electrode sheet coated with a negative electrode active material layer on one side (the unit area coating weight of the negative electrode active material on one side of the negative electrode sheet was 103mg/1540.25mm2 ). After that, the above steps were repeated on the other surface of the copper foil to obtain a negative electrode sheet coated with a negative electrode active material layer on both sides. The negative electrode sheet was then cold pressed and cut into pieces for standby use.
示例性地，参照图6和图7，负极极片采用与第一极片类似的结构。具体地，L1＝L2＝1.02m。W2为60.2mm，W1为4mm，W4为3.2mm。6 and 7 , the negative electrode sheet adopts a structure similar to that of the first electrode sheet. Specifically, L1=L2=1.02 mm. W2 is 60.2 mm, W1 is 4 mm, and W4 is 3.2 mm.
<隔膜的制备><Preparation of Separator>
将氧化铝涂层设置于基膜的一个表面上，以制备出隔膜。其中，基膜选用厚度8μm的聚乙烯基膜，氧化铝涂层的厚度为2μm。The aluminum oxide coating is disposed on one surface of the base film to prepare a diaphragm, wherein the base film is a polyethylene base film with a thickness of 8 μm, and the thickness of the aluminum oxide coating is 2 μm.
<电解液的制备><Preparation of Electrolyte>
在含水量小于10ppm的环境下，将碳酸乙烯酯(EC)、碳酸甲乙酯(EMC)按照质量比70:30混合得到非水有机溶剂，然后向非水有机溶剂中加入六氟磷酸锂(LiPF6)和添加剂氟代碳酸乙烯酯(FEC)溶解并混合均匀，得到电解液。其中，基于电解液的质量，LiPF6的质量百分含量为15％，氟代碳酸乙烯酯的质量百分含量为1％，余量为非水有机溶剂。In an environment with a water content of less than 10 ppm, ethylene carbonate (EC) and ethyl methyl carbonate (EMC) are mixed at a mass ratio of 70:30 to obtain a non-aqueous organic solvent, and then lithium hexafluorophosphate (LiPF6 ) and an additive fluoroethylene carbonate (FEC) are added to the non-aqueous organic solvent to dissolve and mix uniformly to obtain an electrolyte. Based on the mass of the electrolyte, the mass percentage of LiPF6 is 15%, the mass percentage of fluoroethylene carbonate is 1%, and the balance is the non-aqueous organic solvent.
<电化学装置的制备><Preparation of electrochemical device>
将上述制备得到的负极极片、隔膜以及正极极片按顺序堆叠卷绕得到具有卷绕结构的电极组件。将电极组件安装到铝壳内，经过辊边、注液、化成、脱气、整形等工艺流程得到电化学装置,电化学装置为直径为18mm的18650锂离子电芯。化成过程具体为：在25℃，将电化学装置以0.02C恒流充电至3.3V，再以0.1C恒流充电至3.6V。The negative electrode sheet, separator and positive electrode sheet prepared above are stacked and wound in sequence to obtain an electrode assembly with a winding structure. The electrode assembly is installed in an aluminum shell, and an electrochemical device is obtained through rolling, liquid injection, formation, degassing, shaping and other process flows. The electrochemical device is a 18650 lithium-ion battery cell with a diameter of 18mm. The formation process is as follows: at 25°C, the electrochemical device is charged to 3.3V at a constant current of 0.02C, and then charged to 3.6V at a constant current of 0.1C.
按照上述方法，制备出电化学装置。According to the above method, an electrochemical device was prepared.
电化学装置测试方法Electrochemical Device Test Methods
按照下述步骤对电化学装置进行测试，测试过程采用电池测试仪(Neware CT-4016-5V-100A)测试。Follow the steps below to test the electrochemical device using a battery tester (Neware CT-4016-5V-100A).
(一)在25℃恒温箱(科明EH-1000)内静置2小时，将电化学装置充电至100％SOC。具体地，在25℃恒温下，电化学装置以0.5C恒流放电至该电化学装置的放电截止电压(2.5V)，然后以0.5C恒流充电至该电化学装置的充电截止电压(4.2V)，然后以充电截止电压恒压充电至0.05C，此时该电化学装置处于100％的SOC。(i) The electrochemical device was placed in a 25°C thermostat (Coming EH-1000) for 2 hours to charge the electrochemical device to 100% SOC. Specifically, at a constant temperature of 25°C, the electrochemical device was discharged at a constant current of 0.5C to the discharge cut-off voltage (2.5V) of the electrochemical device, then charged at a constant current of 0.5C to the charge cut-off voltage (4.2V) of the electrochemical device, and then charged at a constant voltage of the charge cut-off voltage to 0.05C, at which time the electrochemical device was at 100% SOC.
(二)在25℃恒温箱(科明EH-1000)内静置2小时，将处于100％SOC的电化学装置以0.2C恒流放电至该电化学装置的放电截止电压(2.5V)，测试放电容量，即为电化学装置的额定容量，再以0.5C恒流充电至该电化学装置的充电截止电压(4.2V)，然后以充电截止电压恒压充电至0.05C，此时该电化学装置处于100％的SOC。(ii) After standing in a 25°C constant temperature box (Coming EH-1000) for 2 hours, the electrochemical device at 100% SOC was discharged at a constant current of 0.2C to the discharge cut-off voltage (2.5V) of the electrochemical device, and the discharge capacity was tested, which was the rated capacity of the electrochemical device. Then, the electrochemical device was charged at a constant current of 0.5C to the charge cut-off voltage (4.2V) of the electrochemical device, and then charged at a constant voltage of the charge cut-off voltage to 0.05C, at which time the electrochemical device was at 100% SOC.
(三)将上述处于100％SOC的电化学装置放置到25℃恒温箱(科明EH-1000)内静置2小时，然后在该温度下以与0.1C倍率对应的电流i 1放电10s，测得电压V1；然后再以与1C倍率对应的电流i2放电1s，并测得电压V2；电化学装置的直流电阻为(V1-V2)/(i2-i1)。(III) The electrochemical device at 100% SOC was placed in a 25°C thermostat (Comin EH-1000) for 2 hours, and then discharged at this temperature with a current i 1 corresponding to a 0.1C rate for 10 seconds, and the voltage V1 was measured; then, the device was discharged with a current i2 corresponding to a 1C rate for 1 second, and the voltage V2 was measured; the DC resistance of the electrochemical device was (V1-V2)/(i2-i1).
(四)将上述测试完直流电阻的电化学装置在25℃恒温箱(科明EH-1000)内静置2小时，然后以0.5C恒流放电至该电化学装置的放电截止电压(2.5V)，然后以0.5C恒流充电至该电化学装置的充电截止电压(4.2V)，然后以充电截止电压恒压充电至0.05C，此时该电化学装置处于100％的SOC。(IV) The electrochemical device after the DC resistance test was placed in a 25°C constant temperature box (Coming EH-1000) for 2 hours, then discharged at a constant current of 0.5C to the discharge cut-off voltage (2.5V) of the electrochemical device, then charged at a constant current of 0.5C to the charge cut-off voltage (4.2V) of the electrochemical device, and then charged at a constant voltage of the charge cut-off voltage to 0.05C, at which time the electrochemical device was at 100% SOC.
(五)将上述处于100％SOC的电化学装置25℃恒温箱(科明EH-1000)内静置2小时。然后，保持恒温箱内的温度，并以5C的放电倍率对电化学装置进行放电，直至电化学装置放电至放电截止电压(2.5V)。在放电的过程中，记录该电化学装置的放电参数。(V) The electrochemical device at 100% SOC was placed in a 25°C thermostat (Coming EH-1000) for 2 hours. Then, the temperature in the thermostat was maintained and the electrochemical device was discharged at a discharge rate of 5C until the electrochemical device was discharged to the discharge cut-off voltage (2.5V). During the discharge process, the discharge parameters of the electrochemical device were recorded.
(六)将结束了步骤(五)的电化学装置在25℃恒温箱(科明EH-1000)内静置2小时，然后以0.5C恒流充电至该电化学装置的充电截止电压(4.2V)，然后以充电截止电压恒压充电至0.05C，此时该电化学装置处于100％的SOC。(vi) The electrochemical device that has completed step (v) is placed in a 25°C constant temperature box (Comin EH-1000) for 2 hours, then charged at a constant current of 0.5C to the charge cutoff voltage (4.2V) of the electrochemical device, and then charged at a constant voltage of the charge cutoff voltage to 0.05C, at which time the electrochemical device is at 100% SOC.
(七)重复步骤(五)和步骤(六)，并改变步骤(五)中的放电倍率，记录电化学装置的放电参数。(VII) Repeat steps (V) and (VI), and change the discharge rate in step (V), and record the discharge parameters of the electrochemical device.
其中，电化学装置的环境温度、放电倍率及其对应的放电容量、额定容量、直流电阻等参数如表7。Among them, the ambient temperature, discharge rate and its corresponding discharge capacity, rated capacity, DC resistance and other parameters of the electrochemical device are shown in Table 7.
表7
Table 7
参照表7，实施例6的电化学装置在以15C-20C的高倍率进行放电时能量损耗较低，电化学装置的放电容量与电化学装置的额定容量之比大于或等于99％，可以为用电设备提供更多的电能。电化学装置在以15C的高倍率进行放电时，能够使放电容量达到甚至超过额定容量。Referring to Table 7, the electrochemical device of Example 6 has low energy loss when discharged at a high rate of 15C-20C, and the ratio of the discharge capacity of the electrochemical device to the rated capacity of the electrochemical device is greater than or equal to 99%, which can provide more electric energy for electrical equipment. When the electrochemical device is discharged at a high rate of 15C, the discharge capacity can reach or even exceed the rated capacity.
实施例6的电化学装置的内阻为8.5毫欧(mΩ)，其在以15C-20C的高倍率放电过程中的能量损耗较小，从而提升电化学装置的放电容量，改善电化学装置的放电性能。The internal resistance of the electrochemical device of Example 6 is 8.5 milliohms (mΩ), and the energy loss during the high rate discharge process of 15C-20C is small, thereby increasing the discharge capacity of the electrochemical device and improving the discharge performance of the electrochemical device.
实施例7Example 7
实施例7的电化学装置的制作方法与实施例6的电化学装置的制作方法的不同之处在于：实施例7的正极极片的正极活性材料采用LiNi0.8Co0.1Mn0.1O2。The difference between the manufacturing method of the electrochemical device of Example 7 and the manufacturing method of the electrochemical device of Example 6 is that the positive electrode active material of the positive electrode sheet of Example 7 is LiNi0.8 Co0.1 Mn0.1 O2 .
实施例7的电化学装置测试方法与实施例6的电化学装置测试方法相同。The electrochemical device testing method of Example 7 is the same as the electrochemical device testing method of Example 6.
实施例7的电化学装置的环境温度、放电倍率及其对应的放电容量、额定容量、直流电阻等参数如表8。The ambient temperature, discharge rate and corresponding discharge capacity, rated capacity, DC resistance and other parameters of the electrochemical device of Example 7 are shown in Table 8.
表8
Table 8
参照表8，实施例7的电化学装置在以15C-20C的高倍率进行放电时能量损耗较低，电化学装置的放电容量与电化学装置的额定容量之比大于或等于99％，可以为用电设备提供更多的电能。Referring to Table 8, the electrochemical device of Example 7 has low energy loss when discharged at a high rate of 15C-20C, and the ratio of the discharge capacity of the electrochemical device to the rated capacity of the electrochemical device is greater than or equal to 99%, which can provide more electrical energy for electrical equipment.
实施例8Example 8
实施例8的电化学装置的制作方法与实施例6的电化学装置的制作方法的不同之处在于：实施例8的正极极片的正极活性材料采用LiNi0.95Co0.01Mn0.04O2。The difference between the manufacturing method of the electrochemical device of Example 8 and the manufacturing method of the electrochemical device of Example 6 is that the positive electrode active material of the positive electrode sheet of Example 8 is LiNi0.95 Co0.01 Mn0.04 O2 .
实施例8的电化学装置测试方法与实施例6的电化学装置测试方法相同。The electrochemical device testing method of Example 8 is the same as the electrochemical device testing method of Example 6.
实施例8的电化学装置的环境温度、放电倍率及其对应的放电容量、额定容量、直流电阻等参数如表9。The ambient temperature, discharge rate and corresponding discharge capacity, rated capacity, DC resistance and other parameters of the electrochemical device of Example 8 are shown in Table 9.
表9
Table 9
参照表9，实施例8的电化学装置在以15C-20C的高倍率进行放电时能量损耗较低，电化学装置的放电容量与电化学装置的额定容量之比大于或等于99％，可以为用电设备提供更多的电能。Referring to Table 9, the electrochemical device of Example 8 has low energy loss when discharged at a high rate of 15C-20C, and the ratio of the discharge capacity of the electrochemical device to the rated capacity of the electrochemical device is greater than or equal to 99%, which can provide more electrical energy for electrical equipment.
实施例9Example 9
电化学装置的制作。Fabrication of electrochemical devices .
<正极极片的制作><Production of positive electrode sheet>
与实施例6的区别在于，正极极片采用图10和图11所示的第一极片的结构。具体地，参照图10和图11，L1＝L2＝0.92m。W2为59mm，W1为4mm，W4为3.2mm。第一空箔区沿卷绕方向的外端和内端的角部均设有相同的三角切口，其中，La＝W1＝4mm,W3＝0.5W1＝2mm。The difference from Example 6 is that the positive electrode sheet adopts the structure of the first electrode sheet shown in Figures 10 and 11. Specifically, referring to Figures 10 and 11, L1 = L2 = 0.92m. W2 is 59mm, W1 is 4mm, and W4 is 3.2mm. The corners of the outer and inner ends of the first empty foil area along the winding direction are both provided with the same triangular cutouts, wherein La = W1 = 4mm, W3 = 0.5W1 = 2mm.
<负极极片的制备><Preparation of negative electrode sheet>
与实施例6的区别在于，负极极片采用图10和图11所示的第一极片的结构。参照图10和图11，L1＝L2＝1.02m，W2为60.2mm，W1为4mm，W4为3.2mm。第一空箔区沿卷绕方向的外端和内端的角部均设有相同的三角切口，其中，La＝W1＝4mm,W3＝0.5W1＝2mm。负极极片的切口与正极极片的切口形状、大小相同。The difference from Example 6 is that the negative electrode sheet adopts the structure of the first electrode sheet shown in Figures 10 and 11. Referring to Figures 10 and 11, L1 = L2 = 1.02m, W2 is 60.2mm, W1 is 4mm, and W4 is 3.2mm. The corners of the outer and inner ends of the first empty foil area along the winding direction are both provided with the same triangular cutouts, wherein La = W1 = 4mm, W3 = 0.5W1 = 2mm. The cutout of the negative electrode sheet is the same shape and size as the cutout of the positive electrode sheet.
<隔膜的制备><Preparation of Separator>
与实施例6相同。Same as Example 6.
<电解液的制备><Preparation of Electrolyte>
与实施例6相同。Same as Example 6.
<电化学装置的制备><Preparation of electrochemical device>
与实施例6相同。Same as Example 6.
按照上述方法，制备出电化学装置。According to the above method, an electrochemical device was prepared.
实施例9的电化学装置测试方法与实施例6的电化学装置测试方法相同。The electrochemical device testing method of Example 9 is the same as the electrochemical device testing method of Example 6.
实施例9的电化学装置的环境温度、放电倍率及其对应的放电容量、额定容量、直流电阻等参数如表10。The ambient temperature, discharge rate and corresponding discharge capacity, rated capacity, DC resistance and other parameters of the electrochemical device of Example 9 are shown in Table 10.
表10
Table 10
参照表10，实施例9的电化学装置在以15C-20C的高倍率进行放电时能量损耗较低，电化学装置的放电容量与电化学装置的额定容量之比大于或等于99％，可以为用电设备提供更多的电能。Referring to Table 10, the electrochemical device of Example 9 has low energy loss when discharged at a high rate of 15C-20C, and the ratio of the discharge capacity of the electrochemical device to the rated capacity of the electrochemical device is greater than or equal to 99%, which can provide more electrical energy for electrical equipment.
实施例10Example 10
电化学装置的制作。Fabrication of electrochemical devices .
<正极极片的制作><Production of positive electrode sheet>
与实施例1的区别在于，正极极片采用图14所示的第一极片的结构。具体地，参照图14，L2为0.92m，第一极片共包括10个第一子极耳，10个第一子极耳的尺寸相同，10个第一子极耳的总长L3(K1+K2+……+K10)为0.8m，相邻两个第一子极耳间距相等，D为10mm，沿第一极片展开后的长度方向，第一空箔区的内端和第一主体区的内端间隔第一距离D1为15mm，第一空箔区的外端和第一主体区的外端间隔第二距离D2为15mm。W2为59mm，W1为4mm，W4为3.2mm。The difference from Example 1 is that the positive electrode sheet adopts the structure of the first electrode sheet shown in FIG14. Specifically, referring to FIG14, L2 is 0.92m, the first electrode sheet includes 10 first sub-electrode ears, the 10 first sub-electrode ears have the same size, the total length L3 (K1+K2+...+K10) of the 10 first sub-electrode ears is 0.8m, the distance between two adjacent first sub-electrode ears is equal, D is 10mm, along the length direction of the first electrode sheet after unfolding, the inner end of the first empty foil area and the inner end of the first main body area are separated by a first distance D1 of 15mm, and the outer end of the first empty foil area and the outer end of the first main body area are separated by a second distance D2 of 15mm. W2 is 59mm, W1 is 4mm, and W4 is 3.2mm.
<负极极片的制备><Preparation of negative electrode sheet>
与实施例1的区别在于，负极极片采用图14所示的第一极片的结构。参照图14，L2为1.02m，第一极片共包括10个第一子极耳，10个第一子极耳的尺寸相同，10个第一子极耳的总长L3(K1+K2+……+K10)为0.9m；相邻两个第一子极耳间距D相等，D为10mm，沿第一极片展开后的长度方向，第一空箔区的内端和第一主体区的内端间隔第一距离D1为15mm，第一空箔区的外端和第一主体区的外端间隔第二距离D2为15mm。W2为60.2mm，W1为4mm，W4为3.2mm。The difference from Example 1 is that the negative electrode plate adopts the structure of the first electrode plate shown in Figure 14. Referring to Figure 14, L2 is 1.02m, the first electrode plate includes 10 first sub-electrode ears, the sizes of the 10 first sub-electrode ears are the same, and the total length L3 (K1+K2+...+K10) of the 10 first sub-electrode ears is 0.9m; the distance D between two adjacent first sub-electrode ears is equal, D is 10mm, along the length direction of the first electrode plate after unfolding, the inner end of the first empty foil area and the inner end of the first main body area are separated by a first distance D1 of 15mm, and the outer end of the first empty foil area and the outer end of the first main body area are separated by a second distance D2 of 15mm. W2 is 60.2mm, W1 is 4mm, and W4 is 3.2mm.
<隔膜的制备><Preparation of Separator>
与实施例6相同。Same as Example 6.
<电解液的制备><Preparation of Electrolyte>
与实施例6相同。Same as Example 6.
<电化学装置的制备><Preparation of electrochemical device>
与实施例6相同。Same as Example 6.
按照上述方法，制备出电化学装置。According to the above method, an electrochemical device was prepared.
实施例10的电化学装置测试方法与实施例6的电化学装置测试方法相同。The electrochemical device testing method of Example 10 is the same as the electrochemical device testing method of Example 6.
实施例10的电化学装置的环境温度、放电倍率及其对应的放电容量、额定容量、直流电阻等参数如表11。The ambient temperature, discharge rate and corresponding discharge capacity, rated capacity, DC resistance and other parameters of the electrochemical device of Example 10 are shown in Table 11.
表11
Table 11
参照表11，实施例10的电化学装置在以15C-20C的高倍率进行放电时能量损耗较低，电化学装置的放电容量与电化学装置的额定容量之比大于或等于99％，可以为用电设备提供更多的电能。Referring to Table 11, the electrochemical device of Example 10 has low energy loss when discharged at a high rate of 15C-20C, and the ratio of the discharge capacity of the electrochemical device to the rated capacity of the electrochemical device is greater than or equal to 99%, which can provide more electrical energy for electrical equipment.
对比例2Comparative Example 2
INR18650-25R(18650电芯)；INR18650-25R (18650 battery);
对比例2的INR18650-25R电芯的测试方法与实施例6的电化学装置测试方法相同。The test method of the INR18650-25R battery cell of Comparative Example 2 is the same as the test method of the electrochemical device of Example 6.
对比例2的INR18650-25R电芯的环境温度、放电倍率及其对应的放电容量、额定容量、直流电阻等参数如表12。The ambient temperature, discharge rate and corresponding discharge capacity, rated capacity, DC resistance and other parameters of the INR18650-25R battery cell of Comparative Example 2 are shown in Table 12.
表12
Table 12
参照表7至表12，相较于INR18650-25R电芯，实施例6-10的电化学装置，在以15C-20C的高倍率进行放电时能量损耗较低，具有更高的放电容量。Referring to Tables 7 to 12, compared with the INR18650-25R battery cell, the electrochemical devices of Examples 6 to 10 have lower energy loss and higher discharge capacity when discharged at a high rate of 15C to 20C.
参照表12，INR18650-25R电芯在以20C的倍率放电时，电芯的电流切断装置(CID)启动并断开放电电路，INR18650-25R电芯仅能释放出部分容量。示例性地，电池测试仪(Neware CT-4016-5V-100A)可以测出从100％SOC到CID启动时放出的容量，即表6中的2063mAh。Referring to Table 12, when the INR18650-25R battery cell is discharged at a rate of 20C, the current cut-off device (CID) of the battery cell is activated and disconnects the discharge circuit, and the INR18650-25R battery cell can only release part of its capacity. For example, the battery tester (Neware CT-4016-5V-100A) can measure the capacity released from 100% SOC to the time when the CID is activated, which is 2063mAh in Table 6.
参照表12，INR18650-25R电芯在以15C-20C的倍率放电时，电芯内部温度较高，对电解液性能影响较大，影响放电性能和放电容量。Referring to Table 12, when the INR18650-25R battery cell is discharged at a rate of 15C-20C, the internal temperature of the battery cell is relatively high, which has a greater impact on the performance of the electrolyte, affecting the discharge performance and discharge capacity.
| Application Number | Priority Date | Filing Date | Title |
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| CN202311828023.7 | 2023-12-27 | ||
| CN202311828023.7ACN117638251A (en) | 2023-12-27 | 2023-12-27 | Electrochemical device, battery pack and electric equipment |
| Publication Number | Publication Date |
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| WO2025140137A1true WO2025140137A1 (en) | 2025-07-03 |
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| PCT/CN2024/141587PendingWO2025140137A1 (en) | 2023-12-27 | 2024-12-23 | Electrochemical apparatus, battery pack and electrical device |
| Country | Link |
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| CN (1) | CN117638251A (en) |
| WO (1) | WO2025140137A1 (en) |
| Publication number | Priority date | Publication date | Assignee | Title |
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| CN117638251A (en)* | 2023-12-27 | 2024-03-01 | 厦门新能达科技有限公司 | Electrochemical device, battery pack and electric equipment |
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN101867069A (en)* | 2009-05-07 | 2010-10-20 | 东莞新能源科技有限公司 | Power type lithium ion battery with heat dispersion performance |
| CN113078364A (en)* | 2021-03-29 | 2021-07-06 | 中南大学 | Manufacturing method of high-energy-density aluminum-shell lithium ion battery |
| CN216288850U (en)* | 2021-11-25 | 2022-04-12 | 宁德时代新能源科技股份有限公司 | Battery cell, battery and power consumption device |
| CN114335754A (en)* | 2021-12-24 | 2022-04-12 | 珠海冠宇电池股份有限公司 | Battery with a battery cell |
| CN217086626U (en)* | 2021-12-17 | 2022-07-29 | 东莞凯德新能源有限公司 | Positive electrode current collecting disc structure of full-lug cylindrical battery and battery |
| CN218939775U (en)* | 2022-12-01 | 2023-04-28 | 楚能新能源股份有限公司 | Battery pole piece, battery winding core, battery core pole group and cylindrical battery |
| CN117638252A (en)* | 2023-12-27 | 2024-03-01 | 厦门新能达科技有限公司 | Electrochemical device, battery pack and electric equipment |
| CN117638251A (en)* | 2023-12-27 | 2024-03-01 | 厦门新能达科技有限公司 | Electrochemical device, battery pack and electric equipment |
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN101867069A (en)* | 2009-05-07 | 2010-10-20 | 东莞新能源科技有限公司 | Power type lithium ion battery with heat dispersion performance |
| CN113078364A (en)* | 2021-03-29 | 2021-07-06 | 中南大学 | Manufacturing method of high-energy-density aluminum-shell lithium ion battery |
| CN216288850U (en)* | 2021-11-25 | 2022-04-12 | 宁德时代新能源科技股份有限公司 | Battery cell, battery and power consumption device |
| CN217086626U (en)* | 2021-12-17 | 2022-07-29 | 东莞凯德新能源有限公司 | Positive electrode current collecting disc structure of full-lug cylindrical battery and battery |
| CN114335754A (en)* | 2021-12-24 | 2022-04-12 | 珠海冠宇电池股份有限公司 | Battery with a battery cell |
| CN218939775U (en)* | 2022-12-01 | 2023-04-28 | 楚能新能源股份有限公司 | Battery pole piece, battery winding core, battery core pole group and cylindrical battery |
| CN117638252A (en)* | 2023-12-27 | 2024-03-01 | 厦门新能达科技有限公司 | Electrochemical device, battery pack and electric equipment |
| CN117638251A (en)* | 2023-12-27 | 2024-03-01 | 厦门新能达科技有限公司 | Electrochemical device, battery pack and electric equipment |
| Publication number | Publication date |
|---|---|
| CN117638251A (en) | 2024-03-01 |
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