CN113036148B - Energy storage system based on conductivity-controllable polymer current collector and preparation process thereof - Google Patents
Energy storage system based on conductivity-controllable polymer current collector and preparation process thereof Download PDFInfo
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Abstract
The invention discloses an ETP energy storage system based on a conductivity-controllable polymer current collector, which comprises an electric core assembled by alternately laminating electrode plates, diaphragms and electrolyte, wherein the inner sides of two single-sided electrode plates positioned at the outermost side are respectively provided with a positive active material layer and a negative active material layer, the polarities of the active materials coated on the opposite surfaces of the two adjacent electrode plates are opposite, the electrode plates are filled with liquid or solid electrolyte, and the current collector is a polymer current collector. The invention combines the electronic conductivity design of the current collector to design the active safety function, thereby avoiding the out-of-control performance of the lithium ion electrochemical behavior caused by the short circuit of the battery, avoiding the defects of fire, explosion and the like and realizing the purpose of high-safety batteries.
Description
Technical Field
The invention belongs to the technical field of energy storage systems, and particularly relates to an ETP energy storage system based on a conductivity-controllable polymer current collector.
Background
Lithium ion batteries have the advantage of high energy density, and thus are widely used in modern life, but at present, lithium ion batteries still cannot meet the requirement of users for seeking longer standby time, and therefore, the development of battery products with higher energy density is an urgent need in the industry.
The solid-state lithium ion battery has a good application prospect as a battery with the highest energy density theoretically, but the current solid-state lithium ion battery usually adopts metal as a current collector, and a plurality of technical problems occur in practical application, for example, aluminum or copper is used as the current collector, once the battery is subjected to internal short circuit, the local current density is increased, the whole battery can be discharged through a short-circuit point, the growth tendency of dendrites in the areas is stronger, a large amount of energy is released through the short-circuit point in a short time (at most 70% of the energy is released in 60 s), the temperature is rapidly increased, decomposition of positive and negative electrode active substances and combustion of electrolyte are caused, and the battery can be ignited and exploded under severe conditions.
The reason why the above-mentioned circumstances appears is when the short circuit phenomenon (or acupuncture simulation short circuit ageing), the high electron conductivity of the metal of aluminium or copper mass flow body makes the electron circulate in the twinkling of an eye fast, lithium ion current carries out the embedding of lithium ion with very big current density at once and deviates from at the short circuit point position, use graphite as an example with the negative pole, lithium dendrite problem can appear in the release of extremely quick lithium ion, the positive pole does not appear quick ionic transfer and leads to crystal structure destruction, all can aggravate battery electric core body failure more than, and then thermal runaway and spontaneous combustion explosion phenomenon appear.
While the volume resistivity of the metal current collector, such as aluminum foil, is 2.85 x 10-8The volume resistivity of the conductive bottom coating is generally 1-5 omega cm, the volume resistivity of the active material layer of the positive electrode is generally 20 omega cm, the volume internal resistivity of the aluminum foil metal current collector is far lower than the volume internal resistivity of the active material layer by 9 orders of magnitude, from the safety perspective, when short circuit occurs, electrons can instantly flow to a short circuit point due to the excellent conductivity of the aluminum foil substrate of the negative electrode, energy is applied to the short circuit point very quickly, so that uneven local deposition of lithium ions is caused, namely, a lithium ion out-of-control and lithium insertion-out process occurs, so that a lithium dendrite phenomenon is caused, thermal runaway is caused, and explosion or spontaneous combustion is caused.
Disclosure of Invention
In order to solve the problems, the invention provides an ETP energy storage system based on a conductivity-controllable polymer current collector.
The technical solution for achieving the above purpose is as follows:
an energy storage system, characterized by: the energy storage system comprises at least one battery cell, wherein the at least one battery cell comprises a positive electrode, a diaphragm, electrolyte and a negative electrode, the inner side surfaces of two electrode plates of the at least one battery cell located on the outermost side are respectively provided with a positive electrode active material layer and a negative electrode active material layer, only the electrode plate with the positive electrode material layer arranged on the inner side is a total positive electrode plate, only the electrode plate with the negative electrode material layer arranged on the inner side is a total negative electrode plate, the electrode plate between the two electrode plates located on the outermost side is a bipolar electrode plate, the two side surfaces of the bipolar electrode plate are respectively provided with the positive electrode active material layer and the negative electrode active material layer, the polarities of the active material layers arranged on the opposite surfaces of the two adjacent electrode plates are opposite, the electrolyte is filled in the energy storage system, the electrode plates comprise a current collector, and the current collector comprises a polymer material.
In a further improvement, it is preferable that the polymer material includes a conductive polymer and/or a conductive polymer, and the conductive polymer includes at least one of polyaniline, polythiophene, or polypyrrole.
For further improvement, the weight ratio of the polyaniline to the polypyrrole is preferably 60:40 or 50: 50.
For further improvement, the weight ratio of the polyaniline to the polypyrrole to the polythiophene is preferably 50:40:10 or 50:30: 20.
Further improved, preferably, the non-conductive polymer material needs to be subjected to conductive treatment, that is, a conductive agent component is added into the polymer, mixed and dispersed, and a casting process is adopted to prepare the conductive polymer current collector film.
In a further improvement, the conductive agent is at least one or more of conductive carbon black SPli, conductive graphite KS-6, carbon nanotubes, carbon nanofibers or graphene.
In a further improvement, the electrolyte is preferably a liquid electrolyte or a solid electrolyte.
Further improved, preferably, the current collector has a conductive polymer two-dimensional film structure, and the thickness of the two-dimensional film is 10-100 um.
For further improvement, the volume electronic conductivity of the polymer current collector preferably ranges from 1S/cm to 10S/cm.
The polymer current collector adopts a conductive high molecular polymer or a composite conductive high molecular made of a polymer and conductive agent blend to replace the traditional foil as the current collector. (1) The structure of the conductive high molecular polymer is that the molecular structure of the conductive high molecular polymer contains a conjugated long chain structure, and pi electrons in a delocalized double bond can migrate on a molecular chain to form current, so that the inherent conductivity of the high molecular structure is ensured. In such conjugated polymers, the longer the molecular chain, the greater the number of pi electrons, the lower the electron activation energy, i.e., the more easily delocalized the electrons, and the better the conductivity of the polymer. (2) The composite conductive polymer is a material formed by filling various conductive substances in a polymer matrix by different processing technologies. Wherein the filler material provides the conductive properties of the material and the polymer matrix binds the conductive filler together and provides the processability of the material. The performance of the polymer material as the matrix has very important influence on the mechanical strength, heat resistance and aging resistance of the composite conductive polymer material.
Conducting polymer such as one or mixture of polyaniline, polythiophene, polypyrrole, etc., conducting treatment of intrinsic non-conducting matrix polymer material such as one or mixture of PE, PP, PS, PVDF, PTFE, ETFE, i.e. adding conductive agent into polymer, mixing and dispersing, and casting to obtain conductive polymer current collecting membrane; the conductive agent is one or a mixture of more of conductive carbon black, SPli, conductive graphite KS-6, carbon nano tubes, nano carbon fibers, graphene and the like.
An ETP energy storage system based on a conductivity-controllable polymer current collector comprises the following manufacturing process steps:
(1) crushing the polymer in a high-speed crusher and fully mixing; crushing the polymer in a high-speed crusher and fully mixing, if the polymer contains a conductive agent, adding the conductive agent into the mixture for three-dimensional mixing, so that the polymer and the conductive agent are uniformly dispersed;
(2) carrying out melt blending extrusion on the mixture obtained in the step (1) at a certain temperature (180-240), and preparing a conductivity-controllable polymer current collector by adopting a tape casting process;
(3) attaching an active substance film to the conductivity-controllable polymer current collector obtained in the step (2) of coating the carbon coating layer by adopting a dry attaching mode, or directly coating active substance slurry on the conductivity-controllable polymer current collector obtained in the step (2) by adopting a wet method
(4) The preparation of the ETP energy storage system conductivity controllable polymer current collector-based electrode can adopt a dry method attaching mode to attach an active substance film on the conductivity controllable polymer current collector coated with the carbon coating layer, and can also adopt a wet method to directly coat active substance slurry on the conductivity controllable polymer current collector.
(5) The ETP energy storage system adopts a plurality of electrode plates, a battery cell is assembled in a lamination assembly mode that the electrode plates, a diaphragm and electrolyte or solid electrolyte are alternated, and the battery cell is assembled in a mode that a shell is coated outside the battery cell. The outer sides of the two outermost electrodes are not coated or attached with a material layer, and the current collector conducts electricity, so that the battery management system can be connected to the outer sides of the outermost electrodes. The inner side surface of the outermost electrode is respectively coated with a single-sided electrode of a positive electrode material layer and a negative electrode material layer; the internal battery core pole piece comprises an internal current collector, a positive material layer and a negative material layer, wherein the positive material layer and the negative material layer are respectively coated on the surfaces of the two sides of the internal current collector. An internal diaphragm is arranged between the positive material layer and the negative material layer of the outermost single-sided electrode and the adjacent negative material layer and positive material layer of the double-sided electrode, and an internal diaphragm is also arranged between the internal double-sided electrode and the adjacent double-sided electrode. The diaphragm is placed in a mode of tightly attaching to the material layers, and only one diaphragm is needed for each positive material layer and the adjacent negative material layer. Each positive electrode material layer, the diaphragm and the negative electrode material layer form a small power supply unit, independent liquid injection is carried out in each power supply unit, and electrolyte between the power supply unit and the power supply unit cannot flow in a liquid mode. An ETP system is composed of a plurality of such power supply units connected in series.
Compared with the prior art, the invention has the beneficial effects that:
(1) at present, the design of the whole battery electrochemical system from an electronic resistivity mechanism is not available, only the firm and reliable design of an external passive system pack shell, the non-flammable liquid electrolyte and the like are provided, and a system BMS battery management system performs software-level monomer management and control and the like; based on the problem of the short-circuit potential safety hazard of the lithium ion battery, the invention combines the electronic conductivity design of the current collector to design the active safety function, thereby avoiding the out-of-control performance of the lithium ion electrochemical behavior caused by the short circuit of the battery and the like, avoiding the defects of fire, explosion and the like and realizing the purpose of a high-safety battery.
(2) Compared with the traditional energy storage system, the energy storage system has the advantages that the intermediate processes of a single cell, a module and the like are omitted from the direct connection from the electrode to the pack system, the internal part of the energy storage system is formed by connecting a plurality of energy storage unit structures in series, the voltage of a formed device is a plurality of times of an independent electric core, and the cost of the energy storage system can be effectively reduced and the energy density can be improved from the structural design aspect.
(3) The invention uses polymer as a current collector, and obtains an energy storage system with low internal resistance, high controllable safety, low cost, high energy density and power density based on the bipolar ETP (Electrode to Pack system) design of the flexible polymer current collector.
Drawings
Fig. 1 is a diagram of an ETP energy storage system based on a conductivity-controllable polymer current collector according to the present invention.
Fig. 2 is a scanning electron micrograph of the conductivity-controlled polymer current collector at an aniline/polypyrrole weight ratio of 60/40.
Fig. 3 is a charge-discharge curve diagram of an ETP system based on a single lithium iron phosphate-graphite energy storage unit.
Fig. 4 is a charge-discharge curve diagram of an ETP system based on five energy storage units of lithium iron phosphate-graphite.
Figure 5 is a diagram of a packaged ETP device.
Detailed Description
The present invention is described in further detail below with reference to the attached drawing figures.
Referring to fig. 1, an ETP energy storage system based on a conductivity-controllable polymer current collector includes a plurality of electrode sheets, a battery core 100 assembled by alternately stacking electrode sheets, a separator, and an electrolyte, and a casing covering the battery core. Anodal active material layer and negative pole active material layer are established respectively to the medial surface of two electrode slices in the outside, for example outermost outer negative pole piece 130, outer positive pole piece 110 and electric core series connection group 150, electric core series connection group 150's both ends have positive terminal and negative terminal respectively, outer negative pole piece 130 is connected with the negative terminal, outer positive pole piece 110 is connected with the positive terminal, electric core series connection group 150 includes the inside electric core pole piece that a plurality of overlaps set up, be provided with the inside diaphragm 170 that is used for the separation electron to pass through between every two adjacent inside electric core pole pieces, and every two adjacent inside electric core pole pieces constitute a power supply unit each other, a plurality of power supply units establish ties together.
Each internal battery cell pole piece includes an internal current collector 190, a positive electrode material layer N and a negative electrode material layer P, the positive electrode material layer N and the negative electrode material layer P are respectively disposed on two side surfaces of the internal current collector 190, and the specific arrangement mode may adopt feasible modes such as coating, adhesion, coating or doping, and the invention is not limited.
In order to reduce the volume of the whole battery, the internal cell pole pieces and the diaphragm 170 can be tightly attached to each other, so that the occupied space of the internal cell pole pieces is reduced, but the invention is not limited to tightly attaching the internal cell pole pieces and the diaphragm, and the positions between the internal cell pole pieces and the diaphragm 170, such as the frames are arranged at intervals, can be arranged according to the specific use environment; an internal diaphragm 170 is arranged between each positive electrode material layer and the adjacent negative electrode material layer, and in order to enable the internal battery core pole pieces to be tightly attached to the diaphragm 170, the positive electrode material layer P and the negative electrode material layer N are respectively combined with the corresponding internal diaphragms 190, so that the volume of the whole battery core is further reduced. The diaphragm 170 is one of cellulose paper, PP, PE, and ceramic, and has a surface of a randomly piled structure of short fibers with different diameters and irregularities, and holes with different sizes and shapes are formed for ion shuttling.
In order to obtain a proper range of controllable electronic conductivity of a polymer current collector of a diaphragm substrate, preferably the conductivity range is 1S/cm-10S/cm, the maximum value of the volume resistivity of the polymer current collector cannot be higher than the resistivity of a conductive bottom coating and an active carbon layer of a positive electrode material, otherwise the integral internal resistance of a battery is influenced, namely the upper limit of the volume resistivity of the polymer current collector is not more than 1 omega cm, namely the volume electronic conductivity is controlled to be more than 1S/cm, the resistivity of the current collector cannot be greatly different from the resistivity of an active material layer and the conductive bottom coating in orders of magnitude, otherwise, the current cannot be slowly circulated in a short circuit, the strength of an electric field power line cannot be uniformly regulated, and the function of regulating a short circuit safety function is not achieved, the invention aims to prevent the flow of the extreme speed of electrons at a short circuit point, and bring about the phenomenon of surface deposition lithium precipitation caused by the uncontrolled release of lithium ions under the maximum current density, namely, the lower limit of the volume resistivity of the polymer current collector is preferably not less than 0.1 omega cm, namely, the volume electronic conductivity is controlled to be 10S/cm. The current collector may employ method a:
the conductive polymer-based conductivity-controllable polymer current collector comprises, by weight, 62 parts of polyaniline and 38 parts of polypyrrole.
The preparation method of the conductivity-controllable polymer current collector based on the conductive high molecular polymer comprises the following steps:
s1, crushing the two high-molecular conductive materials at high speed and fully mixing;
s2, heating and blending the mixture S1 at a certain temperature (240 ℃) and a rotating speed; (ii) a
S3, fully and uniformly mixing the mixture prepared in the S2, and processing the conductive polymer film at 220 ℃ by combining a tape casting process;
and S4, cooling, slitting and molding the conductive polymer film prepared in the step S3 at room temperature to obtain the conductive polymer-based conductivity-controllable polymer current collector.
The conductivity performance of the conductivity-controllable polymer current collector based on the conductive polymer is evaluated. The method comprises the following specific steps:
the resistivity of the prepared current collector body is tested by adopting a four-probe method, and the current collector body prepared by other conductive polymers in weight ratio is also tested.
TABLE 1 conductivity change for different polyaniline, polypyrrole and polythiophene ratios
| Weight ratio of | Volume resistivity (omega cm) | Bulk conductivity (S/cm) |
| Polyaniline/polypyrrole 60/40 | 0.36 | 2.78 |
| Polyaniline/polypyrrole 50/50 | 0.51 | 1.96 |
| Polyaniline/polypyrrole/polythiophene 50/40/10 | 0.61 | 1.64 |
| Polyaniline/polypyrrole/polythiophene 50/30/20 | 0.58 | 1.72 |
As can be seen from table 1 above, the bulk resistivity of the conductive current collector prepared in the compounding ratio range is 0.1-1 Ω cm in the required range, and is the lowest when the weight ratio of polyaniline/polypyrrole is 60/40.
Fig. 2 is a scanning electron microscope image of a conductivity-controllable polymer current collector with a weight ratio of polyaniline/polypyrrole of 60/40, in which a rod-shaped structure is polyaniline and a clustered substance at the top end of the rod-shaped polyaniline is polypyrrole.
Meanwhile, the invention can adopt a method B to prepare a polymer current collector, which comprises the following steps:
the ETP system of the lithium iron phosphate-graphite (namely, the anode material is lithium iron phosphate, and the cathode material is graphite) based on the conductivity-controllable polymer current collector is composed of a bipolar electrode, a poly-cellulose diaphragm, a lithium hexafluorophosphate electrolyte and a shell.
The preferable bipolar electrode current collector is a controllable conductivity polymer current collector, which is composed of an intrinsic non-conductive polymer and a conductive agent, wherein the polymer accounts for 60 parts by weight, and the conductive agent accounts for 40 parts by weight.
Preferably, the intrinsic non-conductive polymer is a mixture of three polymers, 26 parts of polyethylene, 22 parts of polypropylene and 12 parts of polytetrafluoroethylene;
preferably, the conductive agent is a mixture of a plurality of conductive agents, 30 parts of conductive carbon black, 5 parts of carbon nanotubes and 5 parts of SP Li.
A lithium iron phosphate-graphite (namely, a positive electrode material is lithium iron phosphate, and a negative electrode material is graphite) ETP system based on a polymer current collector with controllable conductivity comprises the following steps:
s1, crushing the two high molecular polymers at high speed and fully mixing;
s2, adding a conductive agent into the mixture obtained in the S1 by using a three-dimensional mixer for fully mixing;
s3, heating and blending the mixture S2 at a certain temperature (180 ℃) and a rotating speed; (ii) a
S4, fully and uniformly mixing the mixture prepared in the S3, and processing the mixture into a conductive polymer film with the thickness of 40 mu at the temperature of 170 ℃ by combining a casting process;
and S5, cooling, slitting and molding the conductive polymer film prepared in the step S4 at room temperature to obtain the conductive polymer-based conductivity-controllable polymer current collector.
The conductivity performance of the conductivity-controllable polymer current collector based on the intrinsic non-conductive polymer is evaluated. The method comprises the following specific steps:
the resistivity of the current collector prepared in S5 was tested using a four-probe method, while other current collectors prepared with polymer/conductive agent weight ratios were also tested. In the table, the polymers are polyethylene/polypropylene 22 parts by weight/polytetrafluoroethylene 13/11/6, and the conductive agent is conductive carbon black/carbon nanotube/SP Li 6/1/1.
TABLE 2 conductivity relationship between three polymers and conductive agent in different ratios
| Weight ratio of | Film thickness (mum) | Volume resistivity (omega cm) | Bulk conductivity (S/cm) |
| Polymer/ |
40 | 4.63 | 0.22 |
| Polymer/conductive agent 70/30 | 40 | 1.45 | 0.69 |
| Polymer/conductive agent 60/40 | 40 | 0.47 | 2.12 |
| Polymer/conductive agent 50/50 | 40 | 0.46 | 2.17 |
As can be seen from table 2 above, the volume resistivity of the polymer current collector decreases as the content of the conductive agent increases gradually, and the decrease in volume resistivity is not significant when the weight ratio of the polymer/conductive agent is 50/50.
An ETP battery was prepared on the basis of the current collector prepared by method B, with the following steps:
and S6, taking the current collector obtained by the 6 sheets in the step S5, and attaching the positive electrode material layer to one surface of the current collector obtained by the 4 sheets, and attaching the negative electrode material layer to the other surface to obtain the bipolar electrode in the 4 sheets of ETP system. And (3) attaching the positive electrode material layer to one surface of the current collector, attaching the negative electrode material layer to one surface of the last current collector to obtain one outermost positive electrode and one outermost negative electrode of the ETP system, and setting the material layer of the outermost electrode as the inner side.
And S6, stacking the outermost single-sided electrode, the diaphragm and the internal bipolar electrode prepared in the step S6 in a mode of anode material layer-diaphragm-cathode material layer, wherein the single-sided electrode is arranged on the outermost layer, and the material-containing layer faces inwards. Each positive electrode material layer and the adjacent negative electrode material layer form a power supply unit, the positive electrode material layers and the adjacent negative electrode material layers are separated by using diaphragms, the diaphragms are tightly attached to the material layers, only one diaphragm is arranged in each power supply unit, and finally, a battery cell containing five power supply units connected in series is formed.
S7, sealing the bottom side of the battery cell obtained in the step S6 at 180 ℃, sealing the top of the battery cell by adopting a notched edge sealing machine so as to reserve a liquid injection hole at the top, then placing the battery cell in a 160 ℃ oven for vacuum baking for 8 hours, injecting liquid, plugging the liquid injection hole by adopting a polytetrafluoroethylene plug, carrying out heat sealing at 180 ℃, and standing for 12 hours.
And S8, leading out a positive electrode tab from the outer side of the outermost positive electrode of the battery cell obtained in the step S7, leading out a negative electrode tab from the outer side of the outermost negative electrode, leading out a potential and temperature monitoring line on each bipolar electrode, and sleeving a protective shell to obtain the ETP system.
The ETP energy storage system based on the conductivity-controllable polymer current collector is evaluated, and specifically the following steps are carried out:
an electrochemical performance test is performed on the ETP system, as shown in fig. 3 and fig. 4, the voltage of a single lithium iron phosphate/graphite battery is 3.2V, 5 ETP energy storage units are 3.2 × 5V — 16.0V, that is, the voltage is increased by corresponding times, the capacity is unchanged, the working voltage window of the ETP system with 5 lithium iron phosphate-graphite power supply units connected in series is increased to 16V, and the voltage window is increased by 5 times compared with that of a single lithium iron phosphate-graphite battery (fig. 3). Because the internal series structure is adopted, a plurality of structural components are omitted, so that the energy density of an ETP system formed by connecting 5 lithium iron phosphate-graphite power supply units in series is much higher than that of an ETP system formed by connecting five lithium iron phosphate batteries in series.
Meanwhile, due to the conductive characteristic of the bipolar electrode and the current collector, the potential and the temperature of a single electrode can be monitored only by connecting the ETP to a battery management system and a temperature monitoring system, and the traditional battery can only monitor a single battery but cannot monitor the electrode. Therefore, the internal condition of the battery can be found in time, and the damage can be avoided.
The temperature and electrode potential of the ETP system charged to 100% state of charge (16V) with a 1C (40mA) current are shown in the table below.
| Electrode number | Temperature (. degree.C.) | Electrode potential (V) |
| ① | 28 | 16.01 |
| ② | 29 | 12.80 |
| ③ | 30 | 9.62 |
| ④ | 28 | 6.41 |
| ⑤ | 28 | 3.21 |
| ⑥ | 28 | 0 |
As shown in fig. 5, the present invention adopts ETP technology to encapsulate a plurality of independent series batteries in a housing package, and adjusts the series number of the internal battery energy storage units to raise the working voltage to tens or hundreds of volts; compared with the traditional external series module system, the ETP process can greatly improve the working voltage, effectively reduce the weight and the volume of the energy storage device monomer and improve the energy density and the power density of the energy storage device. The series connection is carried out along the direction of the power line, and the obtained ETP device has the advantage of obviously low internal resistance.
The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention, and various modifications and changes may be made by those skilled in the art. Any modification, equivalent replacement, or improvement made within the spirit and principle of the present invention should be included in the protection scope of the present invention.
Claims (5)
1. An energy storage system, characterized by: the energy storage system comprises at least one battery cell, wherein the at least one battery cell comprises a positive electrode, a diaphragm, liquid or solid electrolyte and a negative electrode, the inner side surfaces of two electrode plates of the at least one battery cell positioned at the outermost side are respectively provided with a positive electrode active material layer and a negative electrode active material layer, the electrode plate with the positive electrode active material layer arranged only at the inner side is a total positive plate, the electrode plate with the negative electrode active material layer arranged only at the inner side is a total negative plate, the electrode plate positioned between the two electrode plates at the outermost side is a bipolar electrode plate, the two side surfaces of the bipolar electrode plate are respectively provided with the positive electrode active material layer and the negative electrode active material layer, the polarities of the active material layers arranged on the opposite surfaces of the two adjacent electrode plates are opposite, the liquid or solid electrolyte is filled in the energy storage system, the electrode plates comprise polymer current collectors, the polymer current collectors comprise polymer materials, the polymer material comprises a conductive polymer or a non-conductive polymer, and the conductive polymer comprises two or three of polyaniline, polythiophene or polypyrrole; the non-conductive polymer needs to be subjected to conductive treatment, namely, a conductive agent component is added into the non-conductive polymer; the volume electronic conductivity range of the polymer current collector is 1S/cm-10S/cm;
the energy storage system manufacturing process comprises the following specific steps:
(1) crushing a conductive polymer or a non-conductive polymer in a high-speed crusher and fully mixing to obtain a mixture, and when the non-conductive polymer is adopted, adding a conductive agent into the mixture to carry out three-dimensional mixing so that the non-conductive polymer and the conductive agent are uniformly dispersed;
(2) melting, blending and extruding the mixture obtained in the step (1) at the temperature of 180-240 ℃, and preparing a conductivity-controllable polymer current collector by adopting a tape casting process;
(3) attaching an active substance film to the conductivity-controllable polymer current collector obtained in the step (2) of coating the carbon coating layer by adopting a dry attaching mode, or directly coating active substance slurry on the conductivity-controllable polymer current collector obtained in the step (2) by adopting a wet method;
(3) the energy storage system adopts a plurality of electrode plates, a battery cell is assembled in a lamination assembly mode that the electrode plates, a diaphragm and liquid or solid electrolyte are alternated, and the battery cell is assembled in a mode that a shell is coated outside the battery cell; the outer sides of the two outermost electrodes are not coated with a material layer or attached to the material layer, and the outer sides of the outermost electrodes are connected with a battery management system due to the conduction of a current collector; the outermost layer electrode is a single-sided electrode with the inner side surface coated with a positive electrode material layer and a negative electrode material layer respectively; the diaphragms are placed in a manner of being tightly attached to the material layers, and only one diaphragm is needed for each positive material layer and the adjacent negative material layer;
each positive electrode material layer, each diaphragm and each negative electrode material layer form a small power supply unit, electrolyte between the power supply units cannot be mixed with liquid, and the energy storage system is formed by connecting a plurality of power supply units in series.
2. The energy storage system of claim 1, wherein the conductive polymer is polyaniline and polypyrrole, and the weight ratio of the polyaniline to the polypyrrole is 60:40 or 50: 50.
3. The energy storage system of claim 1, wherein the conductive polymer is three of polyaniline, polypyrrole, and polythiophene, and the weight ratio of polyaniline, polypyrrole, and polythiophene is 50:40:10, or 50:30: 20.
4. The energy storage system of claim 1, wherein the conductive agent is one or more of conductive carbon black SPli, conductive graphite KS-6, carbon nanotubes, carbon nanofibers, or graphene.
5. The energy storage system of claim 1, wherein the structure of the current collector is a polymer two-dimensional thin film structure having a thickness of 10-100 μm.
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| CN113540471A (en) * | 2021-07-13 | 2021-10-22 | 四川大学 | Three-dimensional porous current collector material and preparation method and application thereof |
| CN114113839A (en) * | 2021-11-16 | 2022-03-01 | 武汉昊诚锂电科技股份有限公司 | Method for evaluating current collecting capacity of lithium-ion battery current collecting structure |
| CN114069022A (en) * | 2021-11-17 | 2022-02-18 | 鄂尔多斯市紫荆创新研究院 | Single-section high-voltage thin film lithium battery |
| CN114188672B (en) * | 2022-02-17 | 2022-05-13 | 天津普兰能源科技有限公司 | All-solid-state energy accumulator and manufacturing method thereof |
| CN115863532B (en) * | 2022-12-22 | 2024-03-29 | 烯晶碳能电子科技无锡有限公司 | Manufacturing process of bipolar electrode |
Citations (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN101979438A (en) * | 2010-11-25 | 2011-02-23 | 武汉大学 | Preparation method of conductive polypyrrole |
| CN106469825A (en) * | 2015-08-21 | 2017-03-01 | 北京好风光储能技术有限公司 | A kind of high-power high-capacity lithium ion battery and preparation method thereof |
| CN108400017A (en) * | 2018-02-11 | 2018-08-14 | 烯晶碳能电子科技无锡有限公司 | A kind of energy storage device of internal series-connection technique |
| CN108774459A (en) * | 2018-06-05 | 2018-11-09 | 桑德集团有限公司 | A kind of coating and preparation method thereof, battery electrode |
| CN111785925A (en) * | 2020-08-11 | 2020-10-16 | 天津市捷威动力工业有限公司 | Pole piece, application and low-temperature-rise safety lithium ion battery containing pole piece |
Family Cites Families (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JP2010177162A (en) * | 2009-02-02 | 2010-08-12 | Konica Minolta Holdings Inc | Method for manufacturing secondary battery |
| CN110350147A (en) * | 2019-06-06 | 2019-10-18 | 西安交通大学 | A kind of integrated-type tunica fibrosa battery component |
| CN113036148B (en) * | 2021-02-26 | 2022-04-26 | 烯晶碳能电子科技无锡有限公司 | Energy storage system based on conductivity-controllable polymer current collector and preparation process thereof |
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| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN101979438A (en) * | 2010-11-25 | 2011-02-23 | 武汉大学 | Preparation method of conductive polypyrrole |
| CN106469825A (en) * | 2015-08-21 | 2017-03-01 | 北京好风光储能技术有限公司 | A kind of high-power high-capacity lithium ion battery and preparation method thereof |
| CN108400017A (en) * | 2018-02-11 | 2018-08-14 | 烯晶碳能电子科技无锡有限公司 | A kind of energy storage device of internal series-connection technique |
| CN108774459A (en) * | 2018-06-05 | 2018-11-09 | 桑德集团有限公司 | A kind of coating and preparation method thereof, battery electrode |
| CN111785925A (en) * | 2020-08-11 | 2020-10-16 | 天津市捷威动力工业有限公司 | Pole piece, application and low-temperature-rise safety lithium ion battery containing pole piece |
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