Electrochemical capacitor made of compound carbon powder containing glue and preparation method thereof and the carbon dustTechnical field
The invention belongs to electrochemical technology fields, and in particular to one kind compound carbon powder containing glue and preparation method thereof and the carbon dustManufactured electrochemical capacitor.
Background technology
With economic continuous development, the energy, resource and environment etc. become the focal issue of society, find cleaning, can be againRaw and resource-conserving the energy is that human society is very urgent and unusual difficult task.
Currently, in energy field, there are mainly three types of the energy storage devices of type：Battery, physical capacitor and electrochemical capacitorDevice (also referred to as ultracapacitor).Electrochemical capacitor was grown up in recent years between traditional physical capacitor and battery spyProperty between a kind of novel green energy storage device, have fast charging and discharging characteristic, power density greatly (be tens times of common batteriesMore than), have extended cycle life (cycle-index is up to 100,000 times or more), and use temperature range is wide (between -40 DEG C~75 DEG C).BaseIn these special performances, electrochemical capacitor has extraordinary application prospect.
According to the difference of energy storage mechnism, electrochemical capacitor can be divided into double layer capacitor and Faradic pseudo-capacitor two is bigClass.Double layer capacitor is using the interfacial electric double layer capacitance formed between electrode and electrolyte come storage energy, and electrode is logicalFrequently with the porous carbon material with high-specific surface area.Pseudo capacitance capacitor refers to two in electrode surface or body phaseIn dimension or quasi- two-dimensional space, electrode active material carries out underpotential deposition, brings it about quick, reversible chemisorption/desorptionOr oxidation/reduction reaction, to generate specific capacity more higher than double layer capacitor, electrode material is mainly metal oxideAnd conducting polymer.
In order to obtain higher energy density and power density simultaneously, grow up a kind of Novel asymmetric type electricity in recent yearsChemical capacitor (also referred to as hybrid electrochemical capacitor), i.e. a pole of capacitor is double layer electrodes, and another extremely faraday is accurateCapacitance electrode.Non-symmetrical electrochemical supercapacitor combines the advantages of two class electrochemical capacitors, can preferably meet realityLoad requires the energy density of power-supply system and the whole of power density in the application of border.
In each asymmetric electrochemical capacitor of quasi-metal oxides/carbon, PbO2/ C systems, since material price is low andPbO2Electrode fabrication techniques are ripe, are very suitable for manufacture large capacity version energy storage device.
The PbO mentioned in previous literature2The asymmetric electrochemical capacitors of/C, anode are using slim lead-acid battery justPole material, utilizes PbSO4/PbO2The redox reaction of electricity pair, cathode use Coated Activated Carbon or active carbon fiber fabrics, H2SO4Aqueous solution makees electrolyte.Due to carbon electrode equivalent series resistance and electrolyte ion mobile route the problems such as, it is considered that carbonThe thickness of electrode is preferably no more than 0.3mm, even slim positive electrode, it is also difficult to matching.As a result, activated carbon negative electrodeCapacitance much smaller than lead oxide anode, in charge and discharge process, most of positive electrodes are not utilized, and the energy of capacitor is closeIt spends low, can not be more than 20Wh/kg, be less than the one third of battery.In addition, slim positive electrode is also not suitable for manufacture large scale polePlate.
Brown lead oxide/activity charcoal super capacitor that patent 200910115958.4 is announced, just extremely in tablet Ti electrodeUpper pulse electrodeposition brown lead oxide film, cathode are the slurry configured with activated carbon, conductive agent and adhesive, in titanium net directlyIt is prepared by tabletting.The water system for three-dimensional porous ti-supported lead dioxide electric/activated carbon that patent 201210330660.7 is announced is asymmetric superCapacitor, just extremely in three-dimensional porous titanium-based electro-deposition brown lead oxide, cathode is with rice husk Quito mesoporous activated carbon, conductive agent and to glueThe slurry of mixture configuration, on stainless (steel) wire prepared by direct tablet compressing.These are all typical power type super capacitor design mouldsFormula, slim anode are combined with slim cathode, and the matching of capacity is very good, and power density is big but energy density is small, this be byThe bigger portion of gross mass will be accounted in the inactive ingredients (collector, bus-bar, pole, partition board and shell etc.) for constituting capacitorPoint, therefore, energy density is only 1/10th of battery or so.
The hybrid electrochemical capacitor that patent 200910221793.9 is announced, using the slim carbon powder electrodes of multilayer and cathodeThe form that partition board is arranged alternately combination prepares cathode, and the capacity matching for preferably solving cathode and conventional oxidation lead anode is askedTopic, energy density are also significantly improved.But accounting of the negative current collector in cathode gross mass is still very high, energyWhat density improved is limited in scope, while the disadvantage of preparation process complexity is also apparent from.
Existing PbO2The asymmetric electrochemical capacitors of/C, power density is high, has extended cycle life, but its energy density is aobviousIt writes and is less than accumulator, electric vehicle and power battery for hybrid electric vehicle and solar energy and wind energy power plant energy storage electricity is also not achievedThe requirement in pond strongly limits the application range of such capacitor.
Invention content
In order to solve the above technical problems, the purpose of the present invention is to provide a kind of compound carbon powder containing glue and preparation method thereof withElectrochemical capacitor made of the carbon dust, to the mixed capacitor prepared, not only energy density is high, power density is high, but alsoIt has extended cycle life, disclosure satisfy that electric bicycle, battery-operated motor cycle, fork truck, recreational vehicle, mobility scooter for old people, electric vehicle and mixesIt closes the requirement of power batteries, the requirement of automobile and motor vehicle start and stop battery and the solar energy such as power vehicle and wind energy power plant stores upThe requirement of energy device.
In order to achieve the above objectives, technical scheme is as follows：
On the one hand, the present invention provides a kind of modified activated carbon particle, includes each component of following weight percent：Capacitive characterCarbon material 60~80%, conductive agent 15~25% and adhesive 5~15%.
Preferably, the modified activated carbon particle includes each component of following weight percent：Capacitive character carbon material 70%,Conductive agent 25% and adhesive 5%.
Preferably, the capacitive character carbon material is selected from activated carbon, carbon nanotube, carbon nano-fiber, carbon/Carbon composites, stoneAt least one of inkization activated carbon and carbon aerosol.
Preferably, the conductive agent is selected from carbon black, acetylene black, graphite, expanded graphite, conductive carbon black (Super-P), carbon fiberAt least one of dimension, carbon nanotube and graphene.
It is highly preferred that described adhesive is selected from polytetrafluoroethylene (PTFE) (PTFE) lotion, butadiene-styrene rubber (SBR) lotion, asphalt mixtures modified by epoxy resinAt least one in fat liquor, Kynoar (PVDF), fluorubber, polyurethane, carboxymethyl cellulose (CMC) and neopreneKind.
The modified activated carbon particle of the present invention, is granulated using activated carbon, conductive agent and adhesive, passes through different-grain diameterMaterial and material mixture ratio combination, so that activated carbon is dispersed in around large-sized carbon material (such as graphite, expanded graphite), it is micro-The carbon material (such as acetylene black, graphene) of small particle is filled in gap, the three-dimensional conductive network of micro-structure is consequently formed, significantlyThe electric conductivity for improving absorbent charcoal material, reduces equivalent series resistance.
On the other hand, the present invention also provides a kind of preparation method of above-mentioned modified activated carbon particle, include the following steps：
1) suitable capacitive character carbon material and conductive agent are weighed, then first does the capacitive character carbon material and conductive agent that weighIt is mixed, water mixing is added, paste mixture is obtained；Preferably, by first dry-mixed 5 points of the capacitive character carbon material and conductive agent that weighClock adds water and stirs 7~8 hours mixings；
2) after the paste mixture being filtered by vacuum again, described adhesive is added, stirs and evenly mixs, obtains mixed raw material；Preferably, 1~2 hour mixing is stirred；
3) finally by the mixed raw material be dried at powder to get.
Preferably, in step 3), by method comprising the following steps, the mixed raw material is dried into powderEnd：At 50~75 DEG C, the mixed raw material is dried 2~10 hours to after leather hard, two pairs of rollers are carried out to mixing material repeatedlyRoll, while infrared heating mixing material, until mixing material in the form of sheets, graininess, last 120 DEG C of dryings 2 hours, i.e.,.
Preferably, at 50 DEG C, the mixed raw material is dried 8~10 hours to leather hard, or；
Preferably, at 75 DEG C, the mixed raw material is dried 2~3 hours to leather hard.
The preparation method of modified activated carbon particle in the present invention pre-wets and adds in right amount adhesive by material,And two pairs of rollers are held to mixing material and rolls, cure and is dried, stable local bonded structure is formed, carbon material is being improvedBulk density while, it is ensured that the porosity and hydrophily of modified activated carbon particle, to improve activated carbon negative electrode plateEffective capacitance amount.
In another aspect, the present invention also provides a kind of compound carbon powder containing glue, including above-mentioned modified activated carbon particle 70~90Weight % further includes 5~20 weight % of conductive agent, 5~10 weight % of adhesive.
Preferably, the compound carbon powder containing glue includes above-mentioned 90 weight % of modified activated carbon particle, further includes conductive agent 5Weight %, 5 weight % of adhesive.
Further aspect, the present invention also provides a kind of preparation methods of the above-mentioned compound carbon powder containing glue, include the following steps：
(1) suitable modified activated carbon particle and conductive agent are first weighed, then the modified activated carbon particle weighed and will be ledElectric agent is first dry-mixed, adds water mixing, obtains raw mixture；Preferably, the modified activated carbon particle and conductive agent that will be weighedIt first dry-mixed 5 minutes, adds water and stirs 15 minutes mixings；It is highly preferred that the 40 of the total weight of compound carbon powder containing glue prepared are addedThe water mixing of weight %；
(2) suitable amount of adhesive is weighed again, and the adhesive weighed is added in the raw mixture, mixing, and solidification is dryAfter dry, compound carbon powder containing glue is obtained, it is preferable that 10~20 minutes mixings of stirring.
Another aspect, the present invention also provides a kind of hybrid electrochemical capacitor negative plate, including lead collector, the lead collectionThe positive and negative of fluid is equipped with the bisque of composite carbon containing glue, and the layer of carbon dust containing glue is compressed on institute by the above-mentioned layer of compound carbon powder containing glueState the tow sides of lead collector, it is preferable that the thickness of the bisque of composite carbon containing glue is 1.1~1.2mm, density 0.75g/cm3。
Preferably, the layer of carbon dust containing glue is compressed on positive and negative the two of the lead collector by method comprising the following stepsFace：
The carbon dust containing glue is filled into the positive and negative in collector, it is then under vacuum, solid in 45 DEG C by compression mouldingChange 12~24 hours, it is 24 hours dry at 50~70 DEG C, obtain the capacitor that tow sides are equipped with the bisque of composite carbon containing glueNegative plate.
The activated carbon negative electrode plate of the present invention is due in the micro-structural 3 D conductive network and electrode in modified activated carbon particleThree-dimensional conductive network collective effect, greatly reduce the equivalent series resistance of electrode, capacity significantly improves, due to using highThe compression moulding of compound carbon powder containing glue of the compositions such as density modifier active carbon particle, conductive agent and adhesive, carbon electrode also have heightThe characteristic of density effectively inhibits the lead deposit problem of activated carbon negative electrode plate electrode interior in charge and discharge process, electrode to haveThe characteristics of high power capacity and long-life.
In another aspect, the present invention also provides a kind of hybrid electrochemical capacitor, including at least one above-mentioned mixing electrificationLearn capacitor anode plate.
Preferably, the hybrid electrochemical capacitor further includes brown lead oxide positive plate, the brown lead oxide positive plate andAGM partition boards and dilute sulfuric acid electrolyte are equipped between the negative plate.
It is highly preferred that the negative plate is flat, takeup type or tubular type height carries in powder amount, thick shape activated carbon electrodes, it shouldElectrode is the powder electrode with three-dimensional conductive network structure, and shape is pressed on lead collector two sides by containing glue compound carbon powderIt is standby, positive plate preferably 1.1~1.9mm, negative plate preferably 0.9~1.5mm.
The hybrid electrochemical capacitor of the present invention is designed as rich solution type, valve-regulated sealed, the oxygen that when overcharge generatesLead by being deposited on activated carbon negative electrode surface absorbs, and realizes oxygen cycle.
The electrochemical capacitor of the present invention, since activated carbon negative electrode uses modified activated carbon particle, conductive agent and adhesivePrepared by compression moulding, conductive agent and adhesive form three-dimensional conductive network structure around modified activated carbon particle, convenient for preparingThe large capacity carbon electrode of medium-sized, thick size, conductive agent and the good corrosion resistance to sulfuric acid of adhesive, make three inside carbon electrodeTieing up conductive network has fabulous stability and durability, substantially increases the service life of capacitor.
Description of the drawings
Fig. 1 is the structural schematic diagram of the negative plate in the present invention；
Fig. 2 is the principal section figure of the hybrid electrochemical capacitor in the present invention；
Fig. 3 is the positive and negative anodes attachment structure schematic diagram of the hybrid electrochemical capacitor in the present invention；
Fig. 4 is modified activated carbon grain structure schematic diagram in the present invention；
Fig. 5 is the charging and discharging curve of the capacitor of negative plate composition prepared by the embodiment of the present invention 2；
Fig. 6 is with the obtained cycle life curve of the charge and discharge mode of Fig. 5；
Wherein：
1. positive plate, 2. negative plates, 21. lead collectors, 22. Powder electrode layer 3.AGM partition boards, 4. activated carbons, 5. anodesBusbar, 6. negative bus bars, 7. shells, 8. positive terminals, 9, negative terminal, 10. graphite, 11. adhesives, 12. acetylene blacks.
Specific implementation mode
The preferred embodiment that the invention will now be described in detail with reference to the accompanying drawings.
Unless specifically stated otherwise, the reagent in following embodiment can be commercially available from regular channel.
In order to reach the purpose of the present invention, as shown in Figure 1, the hybrid electrochemical capacitor negative plate 2 of the present invention, including it is negativeThe positive and negative of pole lead collector 21, lead collector is equipped with the bisque of composite carbon containing glue 22, and the layer of carbon dust containing glue 22 is by containing glue composite carbonPowder (compound carbon powder containing glue prepared by following embodiments) is suppressed, it is preferable that the thickness of the bisque of composite carbon containing glue is 1.1~1.2mm, density 0.75g/cm3。
In order to reach the purpose of the present invention, as shown in Fig. 2 to 3, hybrid electrochemical capacitor of the invention, including at least oneA above-mentioned hybrid electrochemical capacitor negative plate 2.
In order to further optimize the implementation result of the present invention, hybrid electrochemical capacitor further includes brown lead oxide positive plate1, AGM partition boards 3 and dilute sulfuric acid electrolyte are equipped between brown lead oxide positive plate 1 and negative plate 2.
In order to further optimize the implementation result of the present invention, negative plate 2 is that flat, takeup type or tubular type height carry powder amountIn, thick shape activated carbon electrodes, which is the powder electrode with three-dimensional conductive network structure, by containing glue compound carbon powder in leadPrepared by 21 two sides compression moulding of collector, the preferably 1.1~1.9mm of brown lead oxide positive plate 1, the preferably 0.9~1.5mm of negative plate 2.
In order to further optimize the implementation result of the present invention, hybrid electrochemical capacitor further includes shell, in shell 7Be packaged with five pieces of brown lead oxide positive plates 1 being intervally arranged and six pieces of negative plates 2,1 size of brown lead oxide positive plate be long 68mm,Wide 38mm, thickness 1.40mm are common lead accumulator PbO2Anode；Cathode size is 68mm length and widths 44mm, thickness 2.95mm.
In order to further optimize the implementation result of the present invention, the thickness of AGM partition boards is 1.2mm/10KPa；And be perfusedElectrolyte is dilute sulfuric acid (density 1.26g/cm3).
In order to further optimize the implementation result of the present invention, the top of brown lead oxide positive plate 1 passes through positive bus bar 5It is connected, and the top of negative plate 2 is then connected by negative bus bar 6.
The preparation of 1 modified activated carbon particle of embodiment
Shown in Fig. 4, modified activated carbon particle is granulated 12 by activated carbon 4, graphite powder 10, acetylene black 11, fluorubberIt forms, each component weight ratio is as follows：Activated carbon 70%, graphite powder 20%, acetylene black 5%, fluorubber 5%, wherein activated carbon are adoptedWith specific surface area 1500m2/ g, mesoporous are more than the commercialization activated carbon of 40%, 5-10 μm of average particle size；Graphite powder average grain diameterThe commercially produced product of 800 mesh；Acetylene black uses specific surface area 70m2The quotient of/g, average particle size 35nm, 0.19 Ω cm of powder resistanceIndustry product.
First by activated carbon, graphite powder and dry-mixed 5 minutes of acetylene black, water is added and is tuned into thin pulp shape, stirs 7 hours, it is fully mixedIt is even.Then slurry is filtered, removes apparent moisture, add the ethyl acetate solution of fluorubber, stir 2 hours, fullyMixing.It is 3 hours dry under 75 DEG C of environment, until after leather hard, two pairs of rollers are carried out to mixing material repeatedly and are rolled, while infrared rayHeat mixing material, until powder in the form of sheets, graininess, last 120 DEG C of dryings 2 hours obtain modified activated carbon particle.
The preparation of 2 negative plate of embodiment
Each material component weight ratio of the compound carbon powder containing glue is as follows：Modified activated carbon particle 90%, the stone of the preparation of embodiment 1Ink powder 5%, epoxy resin 5% (lotion), wherein modified activated carbon particle took 40 mesh to sieve through appropriate attrition grinding, did not crossed 100The part of mesh sieve, tapped bulk density 0.65g/cm3；Graphite powder is the commercially produced product of 800 mesh of average grain diameter.
First by dry-mixed 5 minutes of modified activated carbon particle, graphite powder, with the water of 40 weight % of modified activated carbon particle weightWetting is further continued for mixing 15 minutes, and the bicomponent epoxy resin (lotion) (also known as AB glue) through premixing, stirring 10 is then addedMinute, it mixes well, compound carbon powder containing glue is made.The compound carbon powder containing glue is filled to the positive and negative in collector successively again,By hydraulic press compression moulding；Then under 45 DEG C of vacuum environments, cure 12 hours, it is 24 hours dry under 50 DEG C of environment.OftenLateral capacitance electrode material controls thickness in 1.1-1.2mm or so, and density domination is in 0.75g/cm3Left and right, obtains negative plate 2.
Negative electrode lead collector 21：Using pure flat lead, thickness is 7mm or so, then punching and shaping.
Fig. 5 is to measure the reality by the cyclic charging and discharging test instrument (μ C-XCF08) of Zhangjiagang Jin Fan Electrosource, Inc.The charging and discharging curve of the capacitor of example made negative plate composition, by capacitor made from the example by two five pieces of positive plates andThe tandem compound of six pieces of negative plate capacitor cells forms, and appearance and size is：102.2 × 44.2 × 96.2mm × mm × mm (long ×It is wide × high), quality 912g；Nominal voltage 4.0V, electrochemical window 4.8-2.0V；Energy density 20.24Wh/Kg, 44.46Wh/L, and the energy density of capacitor in the prior art is generally 7~8Wh/Kg, i.e. the energy density of the capacitor of the application is remoteFar above the energy density of capacitor in the prior art.
Fig. 6 is can see from the curve with the obtained cycle life curve of the charge and discharge mode of Fig. 5, the application'sThe capacitor deep discharge service life can reach 8000 times or more, and the deep discharge service life of the capacitor to known to can reach traditional lead15 times or more of acid accumulator.
The preparation of 3 modified activated carbon particle of embodiment
The adhesive of modified activated carbon particle is PTFE (content 70%) lotion；Each component weight ratio is as follows：Carbon NanowireDimension 60%, acetylene black 20%, graphene 5%, PTFE (content 70%) lotion 15%.
First by carbon nano-fiber, graphene and dry-mixed 5 minutes of acetylene black, water is added and is tuned into thin pulp shape, stirs 8 hours, fillsDivide mixing.Then slurry is filtered, removes apparent moisture, add PTFE (polytetrafluoroethylene (PTFE)) (content 70%) lotion,Stirring 1 hour, mixes well.It is 2 hours dry under 75 DEG C of environment, until after leather hard, two pairs of rollers stone roller is carried out to mixing material repeatedlyPressure, while infrared heating mixing material, until powder in the form of sheets, graininess, last 120 DEG C of drying 2 hours obtain being modified workProperty charcoal particle.
Remaining is identical with embodiment 2.
The preparation of 4 negative plate of embodiment
Modified activated carbon particle 70%, carbon black 20%, the epoxy resin latex 10% of the preparation of embodiment 3.
First by dry-mixed 5 minutes of modified activated carbon particle, carbon black, moistened with the water of 40 weight % of modified activated carbon particle weightIt is wet, it is further continued for mixing 15 minutes, the bicomponent epoxy resin (lotion) through premixing is then added, is stirred 20 minutes, it is fully mixedIt is even, compound carbon powder containing glue is made.The compound carbon powder containing glue is filled to the positive and negative in collector successively again, by hydraulic press pressureShape is made；Then under 45 DEG C of vacuum environments, cure 24 hours, it is 24 hours dry under 50 DEG C of environment.Per lateral capacitance electrode materialMaterial control thickness is in 1.1-1.2mm or so, and density domination is in 0.75g/cm3Left and right, obtains negative plate 2.
Remaining is identical with embodiment 2.
The preparation of 5 modified activated carbon particle of embodiment
Modified activated carbon particle each component weight ratio is as follows：Carbon aerosol 80%, expanded graphite 5%, fluorubber 15%.
First by dry-mixed 5 minutes of carbon aerosol, expanded graphite, water is added and is tuned into thin pulp shape, stirs 7.5 hours, mixes well.Then slurry is filtered, removes apparent moisture, add the ethyl acetate solution of fluorubber, stirred 1.5 hours, it is fully mixedIt is even.Under 50 DEG C of environment, forced air drying 8 hours (can dry 8-10 hours) repeatedly carries out pair mixing material until after leather hardRoller rolls, while infrared heating mixing material, until powder in the form of sheets, graininess, last 120 DEG C of dryings 2 hours are changedProperty active carbon particle.
Remaining is identical with embodiment 1.
The preparation of 6 negative plate of embodiment
Modified activated carbon particle 80%, carbon black 5%, the epoxy resin latex 15% of the preparation of embodiment 5.
First by dry-mixed 5 minutes of modified activated carbon particle, carbon black, moistened with the water of 40 weight % of modified activated carbon particle weightIt is wet, it is further continued for mixing 15 minutes, the bicomponent epoxy resin (lotion) (also known as AB glue) through premixing is then added, stirs 15 pointsClock mixes well, and compound carbon powder containing glue is made.The compound carbon powder containing glue is filled to the positive and negative in collector successively again, is passed throughCross hydraulic press compression moulding；Then under 45 DEG C of vacuum environments, cure 18 hours, it is 24 hours dry under 50 DEG C of environment.Per sideCapacitance electrode material controls thickness in 1.1-1.2mm or so, and density domination is in 0.75g/cm3Left and right, obtains negative plate 2.
What has been described above is only a preferred embodiment of the present invention, it is noted that for those of ordinary skill in the artFor, without departing from the concept of the premise of the invention, various modifications and improvements can be made, these belong to the present inventionProtection domain.