CN112736302A - Method and device for judging abnormal capacity of battery cell, vehicle and storage medium - Google Patents

Abstract

The embodiment of the invention provides a method and a device for judging the capacity abnormity of a battery cell, a vehicle and a storage medium, wherein the method comprises the following steps: acquiring a battery charging start signal; acquiring a string number of preset first-quantity lowest-voltage battery cell strings when charging starts; acquiring a battery charging end signal; acquiring a string number of a preset second number of highest voltage battery cell strings when charging is finished; and judging whether the preset first number of lowest voltage battery cell strings have battery cell strings with the same string number as the preset second number of highest voltage battery cell strings, and if so, judging that the battery cell strings with the same string number have abnormal battery cell capacity. According to the scheme provided by the embodiment of the invention, if the battery cell strings with the lowest preset first number of voltages at the beginning of charging and the battery cell strings with the highest preset second number of voltages at the end of charging are identified to have the same battery cell strings, the capacity abnormality of the battery cell strings is described.

Description

Method and device for judging abnormal capacity of battery cell, vehicle and storage medium

Technical Field

The invention relates to the technical field of power batteries, in particular to a method and a device for judging abnormal capacity of a battery core, a vehicle and a storage medium.

Background

At present, a power lithium ion battery is used as a mobile energy carrier, is a core component of a new energy automobile, and continuously plays an important role in changing the intelligent living style of people. However, the power lithium ion battery pack is limited by the characteristics of the lithium ion battery, the technical development, the process and the like, and the situation that a single battery cell inside the power lithium ion battery pack is abnormally attenuated still often occurs in the use process of the vehicle at present, so that how to quickly and accurately identify the abnormal battery cell plays an important role in improving the maintenance efficiency and ensuring the safety and normal use of the vehicle.

Disclosure of Invention

The embodiment of the invention discloses a method and a device for judging the capacity abnormity of a battery cell, a vehicle and a storage medium, which can solve or partially solve the problem of the capacity abnormity of the battery cell in the prior art.

The first aspect of the embodiment of the invention discloses a method for judging the capacity abnormality of a battery cell, which comprises the following steps:

acquiring a battery charging start signal;

acquiring a string number of preset first-quantity lowest-voltage battery cell strings when charging starts; the preset first number of lowest-voltage cell strings are obtained by sequencing all the voltage cell strings according to the voltage magnitude, and selecting the preset first number of cell strings from the cell string with the lowest voltage in the high-voltage direction;

acquiring a battery charging end signal;

acquiring a string number of a preset second number of highest voltage battery cell strings when charging is finished; the preset second number of highest-voltage cell strings are obtained by sequencing all the voltage cell strings according to the voltage magnitude, and selecting the preset second number of cell strings from the cell string with the highest voltage in a low-voltage direction;

and judging whether the preset first number of lowest voltage battery cell strings have battery cell strings with the same string number as the preset second number of highest voltage battery cell strings, and if so, judging that the battery cell strings with the same string number have abnormal battery cell capacity.

A second aspect of the present invention discloses a device for determining an abnormal cell capacity, where the device includes:

the charging start signal acquisition module is used for acquiring a battery charging start signal;

the first serial number acquisition module is used for acquiring serial numbers of preset first number lowest voltage battery cell strings when charging starts;

the charging end signal acquisition module is used for acquiring a battery charging end signal;

the second serial number obtaining module is used for obtaining the serial number of the preset second number of highest-voltage battery cell strings when charging is finished;

and the judging module is used for judging whether the preset first number of lowest voltage battery cell strings have battery cell strings with the same string number as the preset second number of highest voltage battery cell strings, and if the preset first number of lowest voltage battery cell strings are the same as the preset second number of highest voltage battery cell strings, the battery cell strings with the same string number have abnormal battery cell capacity.

A third aspect of embodiments of the present invention discloses a vehicle comprising one or more processors; one or more machine-readable media having instructions stored thereon, which when executed by the one or more processors, cause the vehicle to perform the method for determining a cell capacity abnormality disclosed in the first aspect of the embodiments of the present invention.

A fourth aspect of the present invention discloses a computer-readable storage medium, which stores a computer program, where the computer program causes a computer to execute the method for determining an abnormal cell capacity disclosed in the first aspect of the present invention.

Compared with the prior art, the embodiment of the invention has the following beneficial effects: according to the scheme provided by the embodiment of the invention, if the battery cell strings with the lowest preset first number of voltages at the beginning of charging and the battery cell strings with the highest preset second number of voltages at the end of charging are identified to have the same battery cell strings, the capacity abnormality of the battery cell strings is described.

Drawings

In order to more clearly illustrate the technical solutions in the embodiments of the present invention, the drawings needed to be used in the embodiments will be briefly described below, and it is obvious that the drawings in the following description are only some embodiments of the present invention, and it is obvious for those skilled in the art that other drawings can be obtained according to these drawings without creative efforts.

Fig. 1 is a schematic flow chart of a method for determining an abnormal cell capacity according to an embodiment of the present invention;

fig. 2 is a schematic flow chart of another method for determining an abnormal cell capacity according to an embodiment of the present invention;

fig. 3 is a schematic block diagram of a device for determining an abnormal cell capacity according to an embodiment of the present invention.

Detailed Description

The technical solutions in the embodiments of the present invention will be clearly and completely described below with reference to the drawings in the embodiments of the present invention, and it is obvious that the described embodiments are only a part of the embodiments of the present invention, and not all of the embodiments. All other embodiments, which can be derived by a person skilled in the art from the embodiments given herein without making any creative effort, shall fall within the protection scope of the present invention.

It should be noted that the terms "first", "second", "third" and "fourth" etc. in the description and claims of the present invention are used for distinguishing different objects, and are not used for describing a specific order. The terms "comprises," "comprising," and any other variation thereof, are intended to cover a non-exclusive inclusion, such that a process, method, system, article, or apparatus that comprises a list of steps or elements is not necessarily limited to those steps or elements expressly listed, but may include other steps or elements not expressly listed or inherent to such process, method, article, or apparatus.

The embodiment of the invention provides a method for judging the abnormal capacity of a battery cell, which is mainly used for judging the abnormal capacity of the battery cell according to whether the battery cell string with the lowest voltage at the beginning of charging of a power battery is the same as the battery cell string with the highest voltage at the end of charging, and if so, judging that the capacity of the battery cell is abnormal. The following description will be given with reference to specific examples.

As shown in fig. 1, a schematic flow chart of an embodiment of a method for determining an abnormal cell capacity according to an embodiment of the present invention includes:

101. acquiring a battery charging start signal;

generally, obtaining a battery charging start signal means that the battery is about to enter a charging state or just enters the charging state, and specifically, the battery charging start signal may be determined, for example, by a value of a charging state parameter or a message value, where the value reaching a set value is the battery charging start, and the obtained value of the charging state parameter or the message value signal may be regarded as the battery charging start signal;

102. acquiring a string number of preset first-quantity lowest-voltage battery cell strings when charging starts;

the power battery comprises a plurality of battery cell strings, each battery cell string is provided with a string number serial number, the voltage value of each battery cell string is obtained when charging is started, the preset first number of lowest voltage battery cell strings are obtained by sequencing all the voltage battery cell strings according to the voltage magnitude, and the preset first number of battery cell strings are selected from the battery cell string with the lowest voltage in the sequence towards the high voltage direction;

the number of the preset first number of lowest-voltage battery cell strings may be only one, that is, the number of the preset first number of lowest-voltage battery cell strings is the one corresponding to the lowest voltage; in some embodiments, there may be a plurality of the battery cell strings, for example, 3 battery cell strings, and then the string number of the 3 battery cell strings with the lowest voltage is obtained;

103. acquiring a battery charging end signal;

ending charging when the charging is normally carried out to the set SOC value, and ending charging to the default value if the SOC value of the charge cut-off is not set;

104. acquiring a string number of a preset second number of highest voltage battery cell strings when charging is finished;

when charging is finished, acquiring voltage values of all the battery cell strings, wherein the preset second number of the highest voltage battery cell strings are obtained by sequencing all the voltage battery cell strings according to voltage magnitude, and selecting the preset second number of the battery cell strings from the battery cell string with the highest voltage in a low voltage direction;

the number of the preset second number of the highest voltage battery cell strings may be only one, that is, the number of the preset second number of the highest voltage battery cell strings is the one corresponding to the highest voltage; in some embodiments, there may be a plurality of the battery cell strings, for example, 3 battery cell strings, and then the string number of the 3 battery cell strings with the highest voltage is obtained;

105. judging whether the preset first number of lowest voltage cell strings have cell strings with the same number as that of the preset second number of highest voltage cell strings, and if so, judging that the cell strings with the same number as that of the preset second number of lowest voltage cell strings have cell capacity abnormity;

106. and when the capacity of the battery cell string is abnormal, sending alarm information.

Because the voltage increase range of each cell string is basically the same or similar during the charging process, the cell string with the lowest voltage at the beginning of charging cannot be the cell string with the highest voltage at the end of charging. Further, if the string of battery cells is a single battery cell, it indicates that the capacity of the single battery cell is abnormally attenuated or has other problems; if the string of battery cores comprises a plurality of battery cores, the abnormal attenuation of the capacity of at least one battery core or other problems exist.

Further, in the embodiment of the present invention, the serial number of a plurality of (at least 2) lowest voltage cell strings may be obtained at the start of charging, the serial number of a plurality of (at least 2) highest voltage cell strings may be obtained at the end of charging, and it is determined whether there is a cell string with the same serial number, which may detect a plurality of cell strings simultaneously, and may also detect when a plurality of cell strings are abnormal simultaneously, and may also prevent a condition that a plurality of cell strings are similar in abnormal condition to cause a missing detection, where the condition of the missing detection may be, for example: the abnormal conditions of the plurality of battery cell strings are very similar, wherein the battery cell string A is detected to be the lowest voltage battery cell string when the charging is started, but the battery cell string B which is very similar to the battery cell string A is detected to be the highest voltage battery cell string when the charging is finished, and then the detection leakage can occur if the judgment is only carried out according to the lowest and the highest battery cell strings.

The cell string in each embodiment of the present invention includes not only a case where each cell string includes 2 or more than 2 cells, but also a case where each cell string only includes one cell.

The mode of sending the warning information can be various, for example, the big data cloud or the local BMS can judge the above and send the warning information, and the warning information can be sent to background service personnel so as to analyze the fault reason, determine the problem in time and maintain the vehicle, improve the vehicle endurance and performance attenuation problems caused by abnormal reduction of the battery capacity, and improve the user experience.

Further, after acquiring the battery charging start signal, the method may further include a step of determining a battery state, as shown in fig. 2, which is a schematic flow chart of another embodiment of the method for determining abnormal cell capacity according to the embodiment of the present invention, and includes:

201. acquiring a battery charging start signal;

202. acquiring fault state information of a battery system;

in some embodiments, for example, the fault diagnosis of the system may be performed by the BMS to obtain the fault state of the battery system, and the cause of the fault state may include, but is not limited to: the voltage of the monomer is too high, the voltage of the monomer is too low, the temperature is too high, the relay is adhered and the like; when the battery system has no fault, subsequent actions are allowed; when the battery system has a fault, the process is ended;

203. acquiring the validity state of a signal message;

in order to eliminate the influence of the communication fault, in some embodiments, the validity state of the signal message may be determined, specifically, for example, the validity check bit of the message may be read to determine that the check bit is valid when the check bit is a preset value, and subsequent actions may be allowed to be performed; if the check bit is not the preset value, the check bit is invalid, and the process is ended;

204. when the battery system fault state information is no fault and the signal message validity state is valid, acquiring a string number of a preset first number of lowest-voltage battery cell strings at the beginning of charging;

205. acquiring a battery charging end signal;

206. acquiring a string number of a preset second number of highest voltage battery cell strings when charging is finished;

207. judging whether the preset first number of lowest voltage cell strings have cell strings with the same number as that of the preset second number of highest voltage cell strings, and if so, judging that the cell strings with the same number as that of the preset second number of lowest voltage cell strings have cell capacity abnormity;

208. and when the capacity of the battery cell string is abnormal, sending alarm information.

In another embodiment of the foregoing method for determining an abnormal electrical core capacity, by determining the fault state information of the battery system and the validity state of the signal packet, a situation that may affect the determination of the abnormal electrical core capacity is eliminated, so that the subsequent determination of the abnormal electrical core capacity is more accurate. The above manner of determining the fault state information of the battery system and the validity state of the signal message may be understood as determining whether the battery is in a normal charging state, and obtaining a battery charging start signal when the battery is in the normal charging state. Other ways of determining whether the battery is in a normal charging state may also be, for example, ways of determining fault state information of the battery system or determining validity state of the signal message.

An embodiment of the present invention further provides a device for determining an abnormal cell capacity, as shown in fig. 3, which is a schematic block diagram of the device for determining an abnormal cell capacity according to the present invention, and the device includes:

a charging startsignal acquiring module 301, configured to acquire a battery charging start signal;

a battery systeminformation obtaining module 302, configured to obtain battery system fault status information;

a signal messagevalidity acquisition module 303, configured to acquire a signal message validity state;

a first serialnumber obtaining module 304, configured to obtain a serial number of a preset first number of lowest-voltage battery cell strings when charging starts when the battery system fault state information is no fault and the signal packet validity state is valid;

a charge endsignal acquiring module 305, configured to acquire a battery charge end signal;

a second stringnumber obtaining module 306, configured to obtain a string number of a preset second number of highest-voltage battery cell strings when charging is finished;

a determiningmodule 307, configured to determine whether the preset first number of lowest-voltage cell strings have cell strings with the same number as that of the preset second number of highest-voltage cell strings, and if yes, determine that the cell strings with the same number as that of the preset second number of highest-voltage cell strings have cell capacity abnormality;

and thealarm module 308 is configured to send alarm information when there is an abnormal capacity of the cell in the cell string.

The embodiment of the invention also discloses a vehicle which comprises the battery cell capacity abnormity judgment device.

The embodiment of the invention also discloses a computer-readable storage medium which stores a computer program, wherein the computer program enables a computer to execute any one of the above methods for judging the capacity abnormality of the battery cell.

Embodiments of the present invention also disclose a computer program product, wherein, when the computer program product is run on a computer, the computer is caused to execute part or all of the steps of the method as in the above method embodiments.

The embodiment of the present invention also discloses an application publishing platform, which is used for publishing a computer program product, wherein when the computer program product runs on a computer, the computer is caused to execute part or all of the steps of the method in the above method embodiments.

It will be understood by those skilled in the art that all or part of the steps in the methods of the embodiments described above may be implemented by instructions associated with hardware, which may be stored in a computer-readable storage medium, such as a Read-Only Memory (ROM), a Random Access Memory (RAM), a Programmable Read-Only Memory (PROM), an Erasable Programmable Read-Only Memory (EPROM), a One-time Programmable Read-Only Memory (OTPROM), an Electrically Erasable rewritable Read-Only Memory (EEPROM), a Compact Disc Read-Only Memory (CD-ROM), or other Memory, a magnetic disk, a magnetic tape, or a magnetic tape, Or any other medium which can be used to carry or store data and which can be read by a computer.

The method, the device and the storage medium for judging the abnormal capacity of the battery cell disclosed by the embodiment of the invention are described in detail, a specific example is applied in the description to explain the principle and the implementation mode of the invention, and the description of the embodiment is only used for helping to understand the method and the core idea of the invention; meanwhile, for a person skilled in the art, according to the idea of the present invention, there may be variations in the specific embodiments and the application scope, and in summary, the content of the present specification should not be construed as a limitation to the present invention.

Claims (10)

1. A method for judging the capacity abnormality of a battery cell is characterized by comprising the following steps:

acquiring a battery charging start signal;

acquiring a string number of preset first-quantity lowest-voltage battery cell strings when charging starts; the preset first number of lowest-voltage cell strings are obtained by sequencing all the voltage cell strings according to the voltage magnitude, and selecting the preset first number of cell strings from the cell string with the lowest voltage in the high-voltage direction;

acquiring a battery charging end signal;

acquiring a string number of a preset second number of highest voltage battery cell strings when charging is finished; the preset second number of highest-voltage cell strings are obtained by sequencing all the voltage cell strings according to the voltage magnitude, and selecting the preset second number of cell strings from the cell string with the highest voltage in a low-voltage direction;

and judging whether the preset first number of lowest voltage battery cell strings have battery cell strings with the same string number as the preset second number of highest voltage battery cell strings, and if so, judging that the battery cell strings with the same string number have abnormal battery cell capacity.

2. The method for determining battery cell capacity abnormality according to claim 1, further comprising:

judging whether the battery is in a normal charging state or not;

the step of obtaining the string number of the preset first number of lowest voltage cell strings at the start of charging specifically includes:

and if the battery is in a normal charging state, acquiring a string number of a preset first number of lowest-voltage battery cell strings when charging starts.

3. The method for determining the abnormal cell capacity of claim 2, wherein:

the step of determining whether the battery is in a normal charging state specifically includes:

acquiring fault state information of a battery system, and judging whether the battery is in a normal charging state or not according to the fault state information of the battery system;

if the battery is in a normal charging state, the step of obtaining the string number of the preset first-quantity lowest-voltage battery cell string at the beginning of charging specifically comprises:

and if the battery is not in a fault state, acquiring a string number of a preset first number of lowest-voltage battery cell strings when charging starts.

4. The method for determining the abnormal cell capacity of claim 2, wherein:

the step of determining whether the battery is in a normal charging state specifically includes:

acquiring the validity state of a signal message, and judging whether the battery is in a normal charging state or not according to the validity state of the signal message;

if the battery is in a normal charging state, the step of obtaining the string number of the preset first-quantity lowest-voltage battery cell string at the beginning of charging specifically comprises:

and if the validity state of the signal message is valid, acquiring a string number of a preset first number of lowest-voltage battery cell strings when charging starts.

5. The method for determining the abnormal cell capacity of claim 2, wherein:

the step of determining whether the battery is in a normal charging state specifically includes:

acquiring fault state information and a signal message validity state of a battery system, and judging whether the battery is in a normal charging state or not according to the fault state information and the signal message validity state of the battery system;

if the battery is in a normal charging state, the step of obtaining the string number of the preset first-quantity lowest-voltage battery cell string at the beginning of charging specifically comprises:

and if the battery is not in a fault state and the signal message validity state is valid, acquiring the string number of the preset first number of lowest-voltage battery cell strings when charging starts.

6. The method for determining battery cell capacity abnormality according to claim 1, further comprising:

and when the capacity of the battery cell string is abnormal, sending alarm information.

7. The utility model provides an unusual judgement device of electric core capacity which characterized in that includes:

the charging start signal acquisition module is used for acquiring a battery charging start signal;

the first serial number acquisition module is used for acquiring serial numbers of preset first number lowest voltage battery cell strings when charging starts;

the charging end signal acquisition module is used for acquiring a battery charging end signal;

the second serial number obtaining module is used for obtaining the serial number of the preset second number of highest-voltage battery cell strings when charging is finished;

and the judging module is used for judging whether the preset first number of lowest voltage battery cell strings have battery cell strings with the same string number as the preset second number of highest voltage battery cell strings, and if the preset first number of lowest voltage battery cell strings are the same as the preset second number of highest voltage battery cell strings, the battery cell strings with the same string number have abnormal battery cell capacity.

8. The device for determining abnormality in cell capacity according to claim 7, further comprising:

and the alarm device module is used for sending alarm information when the capacity of the electric core string is abnormal.

9. A vehicle, characterized by comprising:

one or more processors; and

one or more machine-readable media having instructions stored thereon that, when executed by the one or more processors, cause the vehicle to perform the cell capacity abnormality determination method of any of claims 1-6.

10. A computer-readable storage medium that stores a computer program, wherein the computer program causes a computer to execute the method for determining a cell capacity abnormality according to any one of claims 1 to 6.

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