CN111564634A - Conductive adhesive, cylindrical lithium ion secondary battery and preparation method thereof - Google Patents
Conductive adhesive, cylindrical lithium ion secondary battery and preparation method thereof Download PDFInfo
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Abstract
The invention belongs to the field of energy storage batteries, and particularly relates to a conductive adhesive, a cylindrical lithium ion secondary battery and a preparation method thereof. The conductive adhesive is prepared from raw materials including silicon rubber, polyvinylidene fluoride, an inorganic conductive agent and an initiator, wherein the mass ratio of the silicon rubber to the polyvinylidene fluoride to the inorganic conductive agent to the initiator is (20-40: 20-40: 25-50): 0.01-1. The cylindrical lithium ion secondary battery comprises a shell with an open upper end, a pole group arranged in the shell, a cap arranged at the opening at the upper end of the shell in a sealing manner, and a current collecting disc arranged between the positive end of the pole group and the cap, wherein the negative end of the pole group is connected with the lower end of the shell through the conductive adhesive, and the positive end of the pole group is connected with the current collecting disc through the conductive adhesive. The battery provided by the invention has excellent power performance and heat dissipation performance, and meanwhile, the battery has a reliable structure and low short circuit rate.
Description
Technical Field
The invention belongs to the field of energy storage batteries, and particularly relates to a conductive adhesive, a cylindrical lithium ion secondary battery and a preparation method thereof.
Background
In the 21 st century, electric vehicles have been a trend to replace fuel vehicles, and lithium ion secondary batteries are important components of electric vehicles. The electric vehicle can be a pure electric vehicle, a plug-in hybrid electric vehicle, a 48V micro hybrid electric vehicle and the like. The plug-in hybrid electric vehicle, particularly the 48V micro hybrid electric vehicle, has a very high requirement on the pulse charge-discharge rate of the battery, the requirement on the pulse charge rate is 20-35C, the requirement on the pulse discharge rate is 30-50C, and the requirement on the capacity of a single battery is 8Ah-20 Ah.
The lithium ion secondary battery may be classified into a cylindrical battery, a square battery, and a pouch battery according to a packaging process.
So far, the laminated soft package battery designed for multiple tabs can better meet the requirements, but the production process of the soft package battery is complex; in the use process, the plastic-aluminum membrane shell is easy to leak liquid, and potential safety hazards exist. Besides, the consistency among the single soft package batteries is poor, the grouping efficiency is low, the service life is short, and the cost is high.
The square battery also has the advantages and disadvantages of the pouch battery described above, and another disadvantage of the square battery is that the heat dissipation performance is inferior to that of the pouch.
The cylindrical cell was developed from a loose 18650 small cell, i.e., a cell with an outer diameter of 18mm and a height of 65 mm. The method is characterized in that the positive and negative electrodes of a common small cylindrical battery are subjected to gap coating when being manufactured, so that in order to weld strip-shaped lugs, an insulating tape is required to be pasted, the number of the lugs which can be led out from the positive and negative electrode plates is 3-4 at most, the requirement of charging and discharging under a certain multiplying power can be met, the requirement of the micro-hybrid electric vehicle on high-multiplying-power charging and discharging cannot be met, the capacity cannot meet the requirement, and the maximum capacity is only 2-2.5Ah usually. But the cylindrical battery has the characteristics of high production efficiency, high battery consistency, high grouping efficiency, long service life, lower cost and the like.
If the process of the cylindrical small battery is introduced into the cylindrical large battery, the number of the lugs is inevitably multiplied in order to ensure the input of current, the difficulty of welding the lugs together is increased, the problem of insufficient welding is easy to occur, the fluctuation of the internal resistance of the battery is large, and the battery is easy to lose efficacy after being grouped; for this purpose, solutions are proposed: shaping the end face of the battery pole group, namely performing high-frequency oscillation and kneading flattening on a foil-shaped body on the end face of the pole group, and then performing laser welding on a current collecting disc. The method has the following defects: firstly, a certain amount of metal dust is easily generated in the flattening process of the positive current collector aluminum foil and the negative current collector copper foil, the battery is slightly short-circuited and self-discharged, the diaphragm is punctured by serious dust, the positive electrode and the negative electrode are short-circuited, and the battery is ignited and exploded; secondly, when the current collecting disc is welded with the end face of the pole group, because of the characteristic of laser welding, the welding of the current collecting disc and the end face of the pole group can only be local spot welding, so that the current is unevenly distributed on the current collecting disc, and the power performance and the heat dissipation performance of the battery are influenced; the area of the end surface current collector empty foil is large, so that the coating area of active substances is reduced, and the energy density of the battery is reduced; and fourthly, the negative electrode current collecting disc is packaged by a steel shell, is generally connected with the bottom of the steel shell through a spot welding process, has larger contact resistance, generates larger heat instantly for more than 50A of charging and discharging current, has local temperature far higher than the battery safety temperature of 80 ℃, can generate side reactions such as battery negative electrode SEI film decomposition, electrolyte decomposition, positive electrode active material decomposition and the like, further raises the battery temperature, and is easy to cause safety problems such as thermal runaway and the like.
Disclosure of Invention
Aiming at the defects of the prior art, the invention provides a conductive adhesive, a cylindrical lithium ion secondary battery and a preparation method thereof.
Specifically, the invention provides the following technical scheme:
the conductive adhesive is prepared from raw materials including silicon rubber, polyvinylidene fluoride, an inorganic conductive agent and an initiator, wherein the mass ratio of the silicon rubber to the polyvinylidene fluoride to the inorganic conductive agent to the initiator is (20-40: 20-40: 25-50): 0.01-1. The silicon rubber matrix has the functions of providing fluidity, enabling the conductive adhesive to be uniformly coated at two ends of a pole group, providing certain bonding strength through crosslinking after heating, forming a high-molecular conductive network by heating and melting polyvinylidene fluoride particles and an inorganic conductive agent, enabling the polyvinylidene fluoride to be strongly bonded with a copper foil, an aluminum foil, a current collector and the like, and promoting thermal polymerization of the silicon rubber by using an initiator.
Preferably, in the conductive adhesive, the mass ratio of the silicone rubber, the polyvinylidene fluoride, the inorganic conductive agent and the initiator is 30-35:30-35: 30-39: 0.01-1.
Preferably, in the above conductive adhesive, the silicone rubber is methyl silicone rubber, methyl vinyl silicone rubber or methyl vinyl phenyl silicone rubber;
and/or the inorganic conductive agent is nano carbon black particles, carbon nano tubes, carbon fibers, graphene or VGCF;
and/or the initiator is di-tert-butylperoxyisopropyl benzene (BIPB), dicumyl peroxide (DCP), Benzoyl Peroxide (BP) or 2, 4-dichlorobenzoyl peroxide (DCBP).
The invention also provides a cylindrical lithium ion secondary battery, which comprises a shell with an opening at the upper end, a pole group arranged in the shell, a cover cap arranged at the opening at the upper end of the shell in a sealing way, and a current collecting disc arranged between the positive pole end of the pole group and the cover cap, wherein the negative pole end of the pole group is bonded with the lower end of the shell through the conductive adhesive, and/or the positive pole end of the pole group is bonded with the current collecting disc through the conductive adhesive.
Preferably, in the cylindrical lithium ion secondary battery, the thickness of the conductive adhesive layer formed by any one of the conductive adhesives is 0-1mm, that is, the overlapping width of the conductive adhesive and the blank regions of the positive and negative electrode foils is 0-1mm, and more preferably 0.1-0.5 mm.
Preferably, in the above cylindrical lithium ion secondary battery, the electrode group includes a positive electrode sheet, a negative electrode sheet, and a separator located between the positive electrode sheet and the negative electrode sheet, the positive electrode sheet includes a positive electrode coating region coated with a positive electrode active material and a positive electrode blank region not coated with the positive electrode active material, and the negative electrode sheet includes a negative electrode coating region coated with a negative electrode active material and a negative electrode blank region not coated with the negative electrode active material;
the width of the negative electrode blank area is 2-4mm, the width of any one of two ends of the diaphragm exceeding the negative electrode coating area is 1-2mm, the width of the positive electrode blank area is 3-5mm, and the width of any one of two ends of the negative electrode coating area exceeding the positive electrode coating area is 0.5-1 mm.
Preferably, among the above-mentioned cylinder lithium ion secondary battery, the current collection dish with the block passes through utmost point ear and links to each other, the current collection dish with utmost point ear passes through laser welding and fixes, the material of the mass flow body is the aluminum alloy, the material of utmost point ear is the aluminum alloy, the other end of utmost point ear with the block passes through laser welding and connects.
Preferably, in the cylindrical lithium ion secondary battery, the housing is a steel shell, and the inner and outer surface layers of the steel shell are subjected to nickel electroplating treatment.
Preferably, in the cylindrical lithium ion secondary battery, the battery case is provided with a rolling groove at the tab, and the rolling groove surrounds the cylinder for a circle.
The invention also provides a preparation method of the cylindrical lithium ion secondary battery, which comprises the following steps:
(1) winding the positive plate, the negative plate and the diaphragm positioned between the positive plate and the negative plate to form a pole group, and coating the conductive adhesive on the negative end of the pole group;
(2) putting the pole group obtained in the step (1) into a shell with an opening at the upper end in a manner that the negative pole end faces downwards, and curing the conductive agent at the negative pole end through high-temperature treatment;
(3) and coating the conductive adhesive on the positive end of the pole group, then adhering a current collecting plate on the positive end, and curing the conductive agent on the positive end through high-temperature treatment.
Preferably, in the above preparation method, after the step (3), a step of injecting an electrolyte and sealing the opening is further included; more preferably, the electrolyte comprises a solvent, a soluble lithium salt and an additive, wherein the solvent is ethylene carbonate, dimethyl carbonate, ethyl methyl carbonate, diethyl carbonate or ethyl acetate, the soluble lithium salt is lithium hexafluorophosphate, and the additive is propane sultone, vinylene carbonate, lithium bis-fluorosulfonyl imide, lithium difluoro oxalato borate, methylene methanedisulfonate, lithium difluoro oxalato phosphate or fluoro carbonate.
Preferably, the preparation method comprises the following steps:
preparing a battery pole group: homogenizing the positive pole → continuously coating the positive pole piece → rolling the positive pole piece → cutting the positive pole piece; homogenizing a negative electrode → continuously coating a negative electrode piece → rolling the negative electrode piece → cutting the negative electrode piece; winding the positive and negative pole pieces and the diaphragm to obtain a pole group;
battery equipment: gluing the negative end of the pole group → putting the pole group into a steel shell → high-temperature melting and curing of negative glue → gluing the positive end of the pole group → bonding of a positive current collecting plate → high-temperature melting and curing of positive glue → a roller groove → vacuum drying → liquid injection → sealing → formation and capacity division.
Preferably, in the above preparation method, the positive electrode sheet is composed of a positive electrode active material, a first conductive agent, a first binder and a first current collector; more preferably, the positive active material is lithium iron phosphate, lithium manganate, lithium nickel cobalt manganese oxide or lithium cobaltate, the first conductive agent is carbon black nanoparticles, carbon nanotubes, carbon fibers, graphene or VGCF, the first binder is polyvinylidene fluoride, styrene butadiene rubber latex or polynitrile, and the first positive current collector is an aluminum foil or a carbon-coated aluminum foil; more preferably, the surface density of the positive electrode active material is 100-300mg/10cm2。
Preferably, in the above preparation method, the negative electrode sheet is composed of a negative electrode active material, a second conductive agent, a second binder and a second current collector; more preferably, the negative active material is artificial graphite, natural graphite, mesocarbon microbeads, silica oxide, silicon carbide or lithium titanate, the second conductive agent is carbon black nanoparticles, carbon nanotubes, carbon fibers, graphene or VGCF, the second binder is sodium carboxymethylcellulose, styrene butadiene rubber latex, polyvinylidene fluoride or polynitrile, and the second current collector is copper foil; more preferably, the surface density of the negative electrode active material is controlled to α × B × C/D, where α is a negative electrode excess coefficient, B is the positive electrode active material surface density, C is the positive electrode active material gram capacity, and D is the negative electrode active material gram capacity.
Preferably, in the above preparation method, the diaphragm is a polypropylene single-layer film, a polyethylene single-layer film or a polypropylene-polyethylene-polypropylene three-layer composite film, or a composite diaphragm composed of the above diaphragm and ceramic, or a ceramic coated diaphragm composed of the above diaphragm, ceramic and PVDF.
The invention has the following beneficial effects:
(1) the power performance and the heat dissipation performance of the battery are greatly improved, the surface temperature of the positive and negative ends of the battery is 35-60 ℃ under the condition of 300-600A high-current charge and discharge of the single battery, and the battery has excellent electric conduction and heat dissipation capacity, while the temperature of the positive and negative ends of the battery prepared by the traditional rubbing and flat welding process is over 80 ℃ under the charge and discharge current of 50A.
(2) Greatly reduces the short circuit rate of the battery assembly process from 1 to 2 percent of the kneading and flat welding process to 0.1 to 0.2 percent.
(3) The reliability of the battery structure is improved, the positive current collector is connected with the current collecting disc through conductive adhesive, the negative electrode is directly connected with the bottom of the shell through the conductive adhesive, silicon rubber in the conductive adhesive and PVDF play a role in bonding strength, and the tensile strength between the positive current collecting disc and the positive end of the pole group and the tensile strength between the negative end of the pole group and the bottom of the steel shell are both larger than that of a flat-rolling welding process.
(4) The consistency of the battery is improved, the conductive agent in the conductive adhesive has the current conduction function, and the conductive agent has a huge specific surface area in the liquid injection process and can uniformly guide the electrolyte to the pole piece.
(5) The coating area of the pole piece is increased, and the battery capacity is 2-3.5% higher than that of the battery prepared by the kneading and flat welding process.
Drawings
Fig. 1 is a schematic structural diagram of a cylindrical lithium ion secondary battery in example 1, wherein 1 represents a battery case, 2 represents a pole group, 3 represents a central steel tube, 4 represents a first conductive adhesive, 5 represents a second conductive adhesive, 6 represents a positive current collecting disc, 7 represents a positive electrode tab, 8 represents a combination cap, 9 represents a CID sheet, and 10 represents an insulating gasket.
FIG. 2 is an expanded view of the electrode assembly of example 1, in which 11-negative electrode coating region, 12-copper foil, 13-separator, 14-positive electrode active material, and 15-aluminum foil.
Detailed Description
The present invention will be described in further detail with reference to specific examples, but the scope of the present invention is not limited thereto.
The experimental procedures used in the following examples are conventional unless otherwise specified. The experimental raw materials and the related equipments used in the following examples are commercially available unless otherwise specified.
Example 1
Embodiment 1 provides a large-size power type cylindrical lithium ion battery, as shown in fig. 1, including a battery case 1, a pole group 2 disposed in the battery case 1, a central steel tube 3 in the pole group 2, a first conductive adhesive 4 coated on a negative end face of the pole group 2, a second conductive adhesive 5 coated on a positive end face of the pole group 2, a positive current collecting disc 6, a positive electrode tab 7 on the positive current collecting disc 6, a combination cap 8, and a CID sheet 9 in the combination cap 8; the material of anodal current collecting disc 6 is the aluminum alloy, anodal utmost point ear 7 material is the aluminum alloy, anodal current collecting disc 6 passes through laser welding with anodal utmost point ear 7 fixedly, be equipped with insulating pad 10 between anodal current collecting disc 6 and anodal utmost point ear 7.
The positive electrode current collecting disc 6 is connected with the positive electrode end face of the electrode group 2 through a second conductive adhesive 5, and the thickness of a conductive adhesive layer formed by the second conductive adhesive 5 is 0.3 mm; the cathode end face of the pole group 2 is connected with the inner surface of the battery shell 1 through a first conductive adhesive 4, and the thickness of a conductive adhesive layer formed by the first conductive adhesive 4 is 0.3 mm. The first conductive adhesive 4 and the second conductive adhesive 5 are both prepared from methyl vinyl silicone rubber, polyvinylidene fluoride particles, nano carbon black particles, carbon nano tubes and a bis-di-penta initiator according to a mass ratio of 29.8: 20: 25.0: 25.0: 0.2.
The electrode group 2 is formed by winding a positive electrode plate, a negative electrode plate and a diaphragm positioned between the positive electrode plate and the negative electrode plate, and fig. 2 is an expanded structural diagram of the electrode group 2, wherein a negative electrode active substance is coated on a copper foil 12 serving as the negative electrode plate to form a negative electrode coating area 11, and the blank local width of the copper foil 12 is 3 mm; the width of each side of the diaphragm 13, which exceeds the negative coating area 11, is 1.5mm, the positive active material is coated on an aluminum foil 15 serving as a positive plate to form a positive coating area 14, and the width of a blank area of the aluminum foil is 4 mm; the width of the negative electrode coating region 11 beyond the positive electrode coating region 14 on each side is 0.5 mm.
The production process of the large-size power type cylindrical lithium ion battery comprises the following steps:
1. preparing a pole group:
(1) preparing a positive pole piece: homogenizing lithium iron phosphate, carbon nano tubes and polyvinylidene fluoride according to the mass ratio of 97.0:1.5:1.5, coating the mixture on a carbon-coated aluminum foil with the thickness of 15 mu m, rolling and cutting to obtain a positive pole piece, wherein the coating surface density of an active material lithium iron phosphate of the positive pole piece is controlled to be (125.0 +/-2.5) mg/10cm2；
(2) Preparing a negative pole piece: homogenizing artificial graphite, nano carbon black particles, a binder CMC and a binder SBR according to a mass ratio of 95.5:2.0:1.5:1.0, coating the homogenate on a copper foil with the thickness of 8 mu m, and rolling and slitting to obtain a negative pole piece, wherein the surface density of the artificial graphite serving as a negative active material is controlled to be (65.0 +/-1.3) mg/10cm2；
(3) Winding a positive pole piece, a negative pole piece and a diaphragm positioned between the positive pole piece and the negative pole piece to form a pole group, wherein the diaphragm is a polypropylene-polyethylene-polypropylene three-layer composite film with the thickness of 16 mu m;
2. battery equipment: gluing the negative end of the pole group → putting the pole group into a steel shell → high-temperature melting and curing of negative glue → gluing the positive end of the pole group → bonding of a positive current collecting plate → high-temperature melting and curing of positive glue → roller groove → vacuum drying → electrolyte injection → sealing → formation and capacity division.
The electrolyte solvent comprises ethylene carbonate, dimethyl carbonate, ethyl methyl carbonate and ethyl acetate, lithium salt is lithium hexafluorophosphate, and additives are propane sultone, vinylene carbonate and lithium bis-fluorosulfonyl imide in mass percentage of 10:35:20: 15:3:3: 4.
Comparative example 1
Comparative example 1 differs from example 1 only in that: and (3) not using a conductive adhesive, performing high-frequency oscillation and flattening on the end faces of the positive electrode and the negative electrode, performing laser welding on the positive electrode current collecting disc and the positive electrode end face of the electrode group, performing laser welding on the negative electrode end face of the electrode group and the negative electrode current collecting disc, and performing spot bottom welding on the negative electrode current collecting disc to the inner surface of the steel shell.
Table 1 shows the comparison of performance data between example 1 and comparative example 1, wherein the strength test method between the positive electrode end face of the electrode assembly and the current collecting plate is as follows: an electronic tensile machine is used, a lower clamp fixes the pole group, and an upper clamp fixes the current collecting disc. And the upper clamp is lifted upwards at the speed of 5mm/min until the pole group and the current collecting disc are completely separated, and the upper clamp stops running. And reading the maximum value, namely the strength between the anode end face of the anode group and the current collecting disc.
The strength test method of the anode end face of the electrode group and the shell is the same as the strength test method of the anode end face of the electrode group and the current collecting disc
The method for testing the charging current and the temperature comprises the following steps: in a thermostat at 25 ℃, a battery in an empty state is charged to a voltage of 3.6V at a constant current of a certain current, and the temperature of the end faces of the positive electrode and the negative electrode is measured when the charging is finished.
The discharge current and temperature test method is the same as the charge current and temperature test method.
TABLE 1
Although the invention has been described in detail hereinabove by way of general description, specific embodiments and experiments, it will be apparent to those skilled in the art that many modifications and improvements can be made thereto based on the invention. Accordingly, such modifications and improvements are intended to be within the scope of the invention as claimed.
Claims (10)
1. The conductive adhesive is characterized by being prepared from raw materials including silicon rubber, polyvinylidene fluoride, an inorganic conductive agent and an initiator, wherein the mass ratio of the silicon rubber to the polyvinylidene fluoride to the inorganic conductive agent to the initiator is (20-40: 20-40: 25-50): 0.01-1.
2. The conductive adhesive as claimed in claim 1, wherein the mass ratio of the silicone rubber, the polyvinylidene fluoride, the inorganic conductive agent and the initiator is 30-35:30-35: 30-39: 0.01-1.
3. The conductive paste as claimed in claim 1 or 2, wherein the silicone rubber is a methyl silicone rubber, a methyl vinyl silicone rubber, or a methyl vinyl phenyl silicone rubber;
and/or the inorganic conductive agent is nano carbon black particles, carbon nano tubes, carbon fibers, graphene or VGCF;
and/or the initiator is bis-tert-butylperoxyisopropyl benzene, dicumyl peroxide, benzoyl peroxide or 2, 4-dichlorobenzoyl peroxide.
4. A cylindrical lithium ion secondary battery, comprising a casing with an open upper end, a pole group arranged in the casing, a cap arranged at the opening of the upper end of the casing in a sealing way, and a current collecting disc arranged between the positive pole end of the pole group and the cap, wherein the negative pole end of the pole group is bonded with the lower end of the casing through the conductive adhesive of any one of claims 1 to 3, and/or the positive pole end of the pole group is bonded with the current collecting disc through the conductive adhesive of any one of claims 1 to 3.
5. The cylindrical lithium ion secondary battery according to claim 4, wherein the thickness of the conductive adhesive layer formed of any one of the conductive adhesives is 0 to 1mm, preferably 0.1 to 0.5 mm;
and/or, the utmost point group includes positive plate, negative pole piece and is located the diaphragm between positive plate and the negative pole piece, positive plate is including the anodal coating area that coats with anodal active material and the anodal blank area that does not coat with anodal active material, the negative pole piece is including the negative pole coating area that coats with negative active material and the negative pole blank area that does not coat with negative active material, wherein, the width in negative pole blank area is 2-4mm, arbitrary end in the both ends of diaphragm surpasss the width in negative pole coating area is 1-2mm, the width in positive pole blank area is 3-5mm, arbitrary end in the both ends in negative pole coating area surpasss the width in positive pole coating area is 0.5-1 mm.
6. A method for manufacturing a cylindrical lithium ion secondary battery is characterized by comprising the following steps:
(1) winding a positive plate, a negative plate and a diaphragm positioned between the positive plate and the negative plate to form a pole group, and coating the conductive adhesive according to any one of claims 1 to 3 on the negative end of the pole group;
(2) putting the pole group obtained in the step (1) into a shell with an opening at the upper end in a manner that the negative pole end faces downwards, and curing the conductive agent at the negative pole end through high-temperature treatment;
(3) coating the conductive adhesive according to any one of claims 1 to 3 on the positive end of the pole group, then adhering a current collecting plate on the positive end, and curing the conductive agent on the positive end through high-temperature treatment.
7. The preparation method according to claim 6, wherein after the step (3), the method further comprises the steps of injecting the electrolyte and sealing; preferably, the electrolyte comprises a solvent, a soluble lithium salt and an additive, wherein the solvent is ethylene carbonate, dimethyl carbonate, ethyl methyl carbonate, diethyl carbonate or ethyl acetate, the soluble lithium salt is lithium hexafluorophosphate, and the additive is propane sultone, vinylene carbonate, lithium difluorosulfonimide, lithium difluorooxalato borate, methyl methane disulfonate, lithium difluorooxalato phosphate or fluoro carbonate.
8. The production method according to claim 6, wherein the positive electrode sheet is composed of a positive electrode active material, a first conductive agent, a first binder, and a first current collector; preferably, the positive active material is lithium iron phosphate, lithium manganate, lithium nickel cobalt manganese oxide or lithium cobaltate, the first conductive agent is carbon black nanoparticles, carbon nanotubes, carbon fibers, graphene or VGCF, the first binder is polyvinylidene fluoride, styrene butadiene rubber latex or polynitrile, and the first current collector is aluminum foil or carbon-coated aluminum foil; more preferably, the formulaThe surface density of the positive electrode active material is 100-300mg/10cm2。
9. The production method according to claim 6, wherein the negative electrode sheet is composed of a negative electrode active material, a second conductive agent, a second binder, and a second current collector; preferably, the negative active material is artificial graphite, natural graphite, mesocarbon microbeads, silica oxide, silicon carbide or lithium titanate, the second conductive agent is carbon black nanoparticles, carbon nanotubes, carbon fibers, graphene or VGCF, the second binder is sodium carboxymethylcellulose, styrene butadiene rubber latex, polyvinylidene fluoride or polyvinyl nitrile, and the second current collector is copper foil.
10. The preparation method according to claim 6, wherein the separator is one or more of a polypropylene film, a polyethylene film, a ceramic film and a polyvinyl fluoride film.
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| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202010512811.5A CN111564634A (en) | 2020-06-08 | 2020-06-08 | Conductive adhesive, cylindrical lithium ion secondary battery and preparation method thereof |
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Cited By (6)
| Publication number | Priority date | Publication date | Assignee | Title |
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| CN113410528A (en) * | 2021-08-04 | 2021-09-17 | 深圳市信宇人科技股份有限公司 | Full-tab lithium battery and packaging preparation process thereof |
| WO2022082924A1 (en) * | 2020-10-19 | 2022-04-28 | 嘉兴模度新能源有限公司 | Structure of cylindrical battery packaged using unheated adhesive bonding process and packaging process therefor |
| CN114824258A (en) * | 2021-01-27 | 2022-07-29 | 恒大新能源技术(深圳)有限公司 | Electrode binder and preparation method thereof, battery pole piece and secondary battery |
| CN114824259A (en) * | 2021-01-27 | 2022-07-29 | 郑州宇通集团有限公司 | Lithium ion battery composite positive plate, preparation method thereof and lithium ion battery |
| CN115084671A (en) * | 2022-05-28 | 2022-09-20 | 楚能新能源股份有限公司 | Method for manufacturing lithium ion battery |
| WO2022237807A1 (en) * | 2021-05-14 | 2022-11-17 | 陕西奥林波斯电力能源有限责任公司 | Conductive connection sheet, pole, current collection disk, and conductive connection structure of large-capacity battery |
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2020
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Cited By (6)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| WO2022082924A1 (en) * | 2020-10-19 | 2022-04-28 | 嘉兴模度新能源有限公司 | Structure of cylindrical battery packaged using unheated adhesive bonding process and packaging process therefor |
| CN114824258A (en) * | 2021-01-27 | 2022-07-29 | 恒大新能源技术(深圳)有限公司 | Electrode binder and preparation method thereof, battery pole piece and secondary battery |
| CN114824259A (en) * | 2021-01-27 | 2022-07-29 | 郑州宇通集团有限公司 | Lithium ion battery composite positive plate, preparation method thereof and lithium ion battery |
| WO2022237807A1 (en) * | 2021-05-14 | 2022-11-17 | 陕西奥林波斯电力能源有限责任公司 | Conductive connection sheet, pole, current collection disk, and conductive connection structure of large-capacity battery |
| CN113410528A (en) * | 2021-08-04 | 2021-09-17 | 深圳市信宇人科技股份有限公司 | Full-tab lithium battery and packaging preparation process thereof |
| CN115084671A (en) * | 2022-05-28 | 2022-09-20 | 楚能新能源股份有限公司 | Method for manufacturing lithium ion battery |
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