Wound cell and battery

Abstract

The application relates to the technical field of batteries, in particular to a winding type battery cell and a battery. The application is characterized in that a first active coating and a second active coating are arranged on the two sides of the current collector of a negative electrode sheet or a positive electrode sheet, the first active coating is arranged on the surface of the side of the current collector close to the winding center, and the second active coating is arranged on the surface of the side of the current collector away from the winding center. When the electric resistance of the first active coating is greater than that of the second active coating, the electric conductivity of the second active coating is greater than that of the first active coating, the high electric conductivity of the second active coating is beneficial to improving the kinetic performance, the battery capacity of the winding type battery can be effectively maintained in long-term circulation, the problem of lithium precipitation is improved, and the service life of the battery is prolonged.

Description

Technical Field

[0001] This application relates to the field of battery technology, specifically to wound battery cells and batteries. Background Technology

[0002] In recent years, with the continuous emergence of consumer electronics products such as smartphones, tablets, and smart bracelets, and the rapid growth of the electric vehicle market, lithium-ion batteries, which power these products, have received increasing attention. Therefore, the lifespan of lithium-ion batteries is crucial.

[0003] For wound-type battery cells, the different circumference of each turn of the wound cell leads to an imbalance of the active materials on both sides of the surface arc near the center of the winding of the same negative electrode sheet. This results in problems such as lithium plating, long-term battery capacity decay, and cycle failure, which seriously affect the battery's lifespan.

[0004] Therefore, a technical solution is needed to address the problem of long-term cycle capacity decay in wound batteries. Summary of the Invention

[0005] In view of this, the present invention provides a wound cell and a battery. This wound cell can effectively maintain battery capacity over long cycles, thereby improving the lithium plating problem and extending battery life.

[0006] To achieve the above-mentioned objectives, the present invention provides the following technical solution:

[0007] The present invention provides a wound battery cell, which includes a wound negative electrode and a wound positive electrode;

[0008] The negative electrode sheet includes a first negative electrode active coating, a current collector, and a second negative electrode active coating arranged sequentially; the first negative electrode active coating is disposed on the surface of the current collector near the center of the curl; the second negative electrode active coating is disposed on the surface of the current collector away from the center of the curl; the resistance of the first negative electrode active coating is greater than the resistance of the second negative electrode active coating;

[0009] The positive electrode includes a first positive active coating, a current collector, and a second positive active coating arranged sequentially; the first positive active coating is disposed on the surface of the current collector near the center of the curl; the second positive active coating is disposed on the surface of the current collector away from the center of the curl; the resistance of the first positive active coating is greater than the resistance of the second positive active coating.

[0010] Preferably, the resistance of the first negative electrode active coating is 1 to 10 Ω.

[0011] Preferably, the resistance of the second negative electrode active coating is 0.1 to 5 Ω.

[0012] Preferably, the resistance of the first positive electrode active coating is 500 to 3000 Ω.

[0013] Preferably, the resistance of the second positive electrode active coating is 100 to 1000 Ω.

[0014] In the embodiments provided by the present invention, the resistance of the first negative electrode active coating being greater than the resistance of the second negative electrode active coating can be adjusted in at least one of the following ways:

[0015] (1) The porosity of the first negative electrode active coating is less than that of the second negative electrode active coating; preferably, the porosity of the first negative electrode active coating is 25% to 40%, and the porosity of the second negative electrode active coating is 25% to 40%.

[0016] (2) The conductive agent content of the first negative electrode active coating is less than that of the second negative electrode active coating; preferably, the conductive agent content of the first negative electrode active coating is 0.5wt% to 15wt%, and the conductive agent content of the second negative electrode active coating is 0.5wt% to 15wt%.

[0017] (3) The conductive agents of the first negative electrode active coating and the second negative electrode active coating are both tubular conductive agents, and the tube wall length of the conductive agent of the first negative electrode active coating is less than the tube wall length of the conductive agent of the second negative electrode active coating; preferably, the tube wall length of the conductive agent of the first negative electrode active coating is 10-25 nm, and the tube wall length of the conductive agent of the second negative electrode active coating is 10-25 nm.

[0018] (4) The graphite orientation index of the first negative electrode active coating is greater than that of the second negative electrode active coating; preferably, the graphite orientation index of the first negative electrode active coating is 1 to 5 and the graphite orientation index of the second negative electrode active coating is 1 to 5.

[0019] The graphite orientation index is the ratio of the peak intensity of graphite on the 004 crystal plane to the peak intensity on the 110 crystal plane in X-ray diffraction.

[0020] (5) The compaction density of the first negative electrode active coating is greater than that of the second negative electrode active coating; preferably, the compaction density of the first negative electrode active coating is 1.2–1.8 g / cm³. 3 The compaction density of the second negative electrode active coating is 1.2–1.8 g / cm³. 3 ;

[0021] The resistance of the first positive electrode active coating is greater than that of the second positive electrode active coating, and this can be controlled by at least one of the following methods:

[0022] (1) The porosity of the first positive electrode active coating is less than that of the second positive electrode active coating; preferably, the porosity of the first positive electrode active coating is 15% to 30%, and the porosity of the second positive electrode active coating is 15% to 30%.

[0023] (2) The conductive agent content of the first positive electrode active coating is less than that of the second positive electrode active coating; preferably, the conductive agent content of the first positive electrode active coating is 0.5wt% to 15wt%, and the conductive agent content of the second positive electrode active coating is 0.5wt% to 15wt%.

[0024] (3) The conductive agents of the first positive electrode active coating and the second positive electrode active coating are both tubular conductive agents, and the tube wall length of the conductive agent of the first positive electrode active coating is less than the tube wall length of the conductive agent of the second positive electrode active coating; preferably, the tube wall length of the conductive agent of the first positive electrode active coating is 10-25 nm, and the tube wall length of the conductive agent of the second positive electrode active coating is 10-25 nm.

[0025] (4) The compaction density of the first positive electrode active coating is greater than that of the second positive electrode active coating; preferably, the compaction density of the first positive electrode active coating is 3.4–4.3 g / cm³. 3 The compaction density of the second positive electrode active coating is 3.4–4.3 g / cm³. 3 .

[0026] Preferably, the components of the first negative electrode active coating or the second negative electrode active coating include:

[0027] The negative electrode active material is 75–99.8 wt%.

[0028] Conductive agent 0.5–15 wt%;

[0029] Adhesive 0.5–15 wt%.

[0030] Preferably, in the first negative electrode active coating or the second negative electrode active coating...

[0031] The negative electrode active material is independently selected from one or more of artificial graphite, natural graphite, mesophase carbon microspheres, soft carbon, and hard carbon;

[0032] The conductive agent is independently selected from one or more of the following: conductive carbon black, carbon fiber, Ketjen black, acetylene black, carbon nanotubes, graphene, Ketjen black, conductive graphite, conductive carbon fiber, carbon nanotubes, metal powder, and carbon fiber.

[0033] The adhesive is independently selected from one or more of styrene-butadiene rubber (SBR), polyacrylic acid, polyurethane, polyvinyl alcohol, polyvinylidene fluoride (PVDF), and copolymers of vinylidene fluoride-fluorinated olefins.

[0034] Preferably, the components of the first positive electrode active coating or the second positive electrode active coating include:

[0035] Positive electrode active material: 75–99.8 wt%;

[0036] Conductive agent 0.5–15 wt%;

[0037] Adhesive 0.5–15 wt%.

[0038] Preferably, in the first positive electrode active coating or the second positive electrode active coating...

[0039] The positive electrode active material is independently selected from one or more of nickel cobalt manganese, lithium iron phosphate, nickel cobalt aluminum, lithium cobalt oxide, and lithium manganese oxide;

[0040] The conductive agent is independently selected from one or more of the following: conductive carbon black, Ketjen black, conductive fiber, conductive polymer, acetylene black, carbon nanotubes, graphene, flake graphite, conductive oxide, and metal particles.

[0041] The adhesive is independently selected from one or more of polyvinylidene fluoride, copolymers of polyvinylidene fluoride and hexafluoropropylene, polyamide, polyacrylonitrile, polyacrylate, polyacrylic acid, polyacrylate, polyvinylpyrrolidone, polyvinyl ether, polymethyl methacrylate, polytetrafluoroethylene, polyhexafluoropropylene, and styrene-butadiene rubber.

[0042] The types of negative electrode active materials, positive electrode active materials, conductive agents, and binders mentioned above are not limited to these; all types recognized by those skilled in the art are within the scope of protection of this invention.

[0043] In this invention, the first negative electrode active coating, the second negative electrode active coating, the first positive electrode active coating, or the second positive electrode active coating may include other functional components recognized in the art, in addition to the components mentioned above.

[0044] Preferably, the thickness of the first negative electrode active coating is 20–75 μm.

[0045] Preferably, the thickness of the second negative electrode active coating is 20–75 μm.

[0046] Preferably, the thickness of the first positive electrode active coating is 20–75 μm.

[0047] Preferably, the thickness of the second positive electrode active coating is 20–75 μm.

[0048] In the embodiments provided by the present invention, the current collector used for the negative electrode is selected from one or more of copper foil, carbon-coated copper foil, and perforated copper foil.

[0049] In the embodiments provided by the present invention, the current collector used in the positive electrode is selected from one or more of aluminum foil, carbon-coated aluminum foil, and perforated aluminum foil.

[0050] In the embodiments provided by the present invention, the wound battery cell may further include one or more of the following: positive tab, negative tab, and separator.

[0051] In some embodiments, the diaphragm is selected from one or both of polyethylene and polypropylene.

[0052] In the embodiments provided by the present invention, the wound battery cell can be a conventional wound cell structure, a wound cell structure with the tabs in the middle, a wound cell structure without tabs, a wound cell structure with three tabs, a wound cell structure with multiple tabs, etc.

[0053] The present invention also provides a battery comprising the above-described wound cell.

[0054] According to an embodiment of the present invention, the battery further includes an electrolyte and / or a casing.

[0055] In some embodiments, the electrolyte is a non-aqueous electrolyte, which includes a non-aqueous organic solvent and a lithium salt.

[0056] In some embodiments, the non-aqueous organic solvent is selected from one or more of ethylene carbonate (EC), propylene carbonate (PC), diethyl carbonate (DEC), fluoroethylene carbonate (FEC), dimethyl carbonate (DMC), methyl ethyl carbonate (EMC), ethylene carbonate, γ-butyrolactone, methyl propyl carbonate, and ethyl propionate.

[0057] In some embodiments, the lithium salt is selected from one or more of LiPF6, LiBF4, LiSbF6, LiClO4, LiCF3SO3, LiAlO4, LiAlCl4, Li(CF3SO2)2N, LiBOB, and LiDFOB.

[0058] Compared with the prior art, the beneficial effects of the present invention are as follows:

[0059] This invention involves setting a first active coating and a second active coating on both sides of the current collector of the negative or positive electrode sheet. The first active coating is set on the surface of the current collector closer to the center of the coil, and the second active coating is set on the surface of the current collector away from the center of the coil. When the resistance of the first active coating is greater than that of the second active coating, the conductivity of the second active coating is greater than that of the first active coating. The high conductivity of the second active coating is beneficial to improving its dynamic performance, thereby effectively maintaining the battery capacity of the wound battery during long-term cycling, thus improving the lithium plating problem and extending the battery's service life. Attached Figure Description

[0060] Figure 1 This is a schematic diagram of the negative electrode structure;

[0061] Figure 2This is a schematic diagram of the positive electrode structure;

[0062] Figure 3 This is a schematic diagram of a conventional core structure;

[0063] Figure 4 Schematic diagram of the core structure with the electrode tab in the middle;

[0064] Figure 5 Comparison of cycle life of wound battery cells.

[0065] Explanation of reference numerals in the attached figures:

[0066] 1. Negative electrode sheet; 1-1 Negative electrode current collector; 1-2 First negative electrode active coating; 1-3 Second negative electrode active coating;

[0067] 2. Positive electrode sheet; 2-1. Positive current collector; 2-2. First positive electrode active coating; 2-3. Second positive electrode active coating;

[0068] 3. Positive electrode ear;

[0069] 4. Negative electrode ear;

[0070] 5. Diaphragm. Detailed Implementation

[0071] This invention discloses a wound battery cell and a battery. Those skilled in the art can refer to the content of this document and appropriately modify the process parameters to achieve the desired result. It should be particularly noted that all similar substitutions and modifications are obvious to those skilled in the art and are considered to be included in this invention. The methods and applications of this invention have been described through preferred embodiments. Those skilled in the art can obviously make modifications or appropriate alterations and combinations to the methods and applications described herein without departing from the content, spirit, and scope of this invention to realize and apply the technology of this invention.

[0072] Terminology Explanation:

[0073] Resistance: refers to the resistance measured across the thickness of the electrode.

[0074] Graphite Orientation Index (OI value): It can represent the degree of orientation of graphite material particles at the electrode level. The OI value affects cycling performance and cycling expansion rate.

[0075] Porosity: refers to the percentage of pore volume in a bulk material to the total volume of the material in its natural state.

[0076] Compacted density: During the manufacturing process of lithium-ion power batteries, compacted density has a significant impact on battery performance. The calculation method is: Compacted density = Areal density / Material thickness.

[0077] There are two main methods for testing coatings. The following are just examples, and there may be other more suitable methods.

[0078] The first method is the film resistance test method: Take an electrode containing the first coating and the second coating, test the electrode thickness D', and directly use a film resistance meter to test the film resistance R'. Scrape off the electrode containing the second coating, and retest the electrode thickness D” and the film resistance R”. For the second coating, its thickness is D, then the resistance of the second coating R2 = (R' ÷ R”) / (D' ÷ D”) × D;

[0079] The second testing method involves assembling the electrode into a button cell and performing an electrochemical impedance spectroscopy (EIS) test. The impedance Rs obtained from the EIS spectrum is then compared with the impedance at the first intersection point of the real axis. The testing process is similar to the first method, the only difference being that one involves directly testing the electrode, while the other involves assembling the electrode into a button cell for EIS testing.

[0080] All chemical components or materials used in this invention are commercially available.

[0081] The present invention will be further illustrated below with reference to the embodiments:

[0082] Example 1: Winded Battery Cell

[0083] 1. Structure and Composition

[0084] In this embodiment, the wound battery cell includes a wound negative electrode 1, a positive electrode 2, a positive electrode tab 3, a negative electrode tab 4, and a separator 5.

[0085] (1) Negative electrode sheet

[0086] Among them, such as Figure 1 As shown, the negative electrode sheet 1 includes a negative electrode current collector 1-1, a first negative electrode active coating 1-2, and a second negative electrode active coating 1-3; the first negative electrode active coating is disposed on the surface of the negative electrode current collector near the center of the curl; the second negative electrode active coating is disposed on the surface of the negative electrode current collector away from the center of the curl.

[0087] The resistance of the first negative electrode active coating is greater than that of the second negative electrode active coating. The resistance of the first negative electrode active coating is 1–10 Ω, and the resistance of the second negative electrode active coating is 0.1–5 Ω.

[0088] The aforementioned first negative electrode active coating comprises: 96.5 wt% active material (artificial graphite), 1.5 wt% conductive agent (conductive carbon black), and 2 wt% binder (sodium carboxymethyl cellulose). The compaction density of the first negative electrode active coating is 1.68 g / cm³. 3 The thickness is 35μm.

[0089] The aforementioned second negative electrode active coating comprises: 96.5 wt% active material (artificial graphite), 2.3 wt% conductive agent (conductive carbon black), and 1.2 wt% binder (sodium carboxymethyl cellulose). The compaction density of the second negative electrode active coating is 1.55 g / cm³. 3 The thickness is 35μm.

[0090] (2) Positive electrode plate

[0091] Among them, such as Figure 2 As shown, the positive electrode 2 includes a positive current collector 2-1, a first positive active coating 2-2, and a second positive active coating 2-3; the first positive active coating is disposed on the surface of the positive current collector near the center of the curl; the second positive active coating is disposed on the surface of the positive current collector away from the center of the curl.

[0092] The resistance of the first positive electrode active coating is greater than that of the second positive electrode active coating. The resistance of the first positive electrode active coating is 500–3000 Ω, and the resistance of the second positive electrode active coating is 100–1000 Ω.

[0093] The aforementioned first positive electrode active coating comprises: 97 wt% active material (lithium cobalt oxide material), 1 wt% conductive agent (acetylene black), and 2 wt% binder (polyvinylidene fluoride). The compaction density of the first positive electrode active coating is 4.15 g / cm³. 3 The thickness is 30μm.

[0094] The aforementioned second positive electrode active coating comprises: 97 wt% active material (lithium cobalt oxide material), 1.8 wt% conductive agent (acetylene black), and 1.2 wt% binder (polyvinylidene fluoride). The compaction density of the second positive electrode active coating is 4 g / cm³. 3 The thickness is 30μm.

[0095] 2. Preparation process

[0096] (1) Preparation of positive electrode:

[0097] a. The slurry of the first positive electrode active material layer and the slurry of the second positive electrode active material layer are uniformly coated on the two surfaces of the aluminum foil, with the first active material layer located on the surface of the current collector closer to the center of the core, and the second active material layer located on the surface of the current collector away from the center of the core.

[0098] b. Dry the coated copper foil, and then roll and slit it to obtain the positive electrode sheet.

[0099] (2) Preparation of negative electrode: Same as positive electrode.

[0100] (3) The positive electrode, negative electrode, and separator are wound into a core.

[0101] (4) After being packaged into a shell, the battery cell of this patent is obtained after baking, liquid injection, formation, sorting, and OCV.

[0102] like Figure 3 As shown, the wound cell in this embodiment has a conventional wound cell structure.

[0103] This technical solution is also applicable to the electrode-center wound core structure. Figure 4 (as shown) and other wound core structures formed by winding (such as infinite loop wound core structure, tri-loop wound core structure, multi-loop wound core structure, etc.).

[0104] Comparative Example 1: Winded Battery Cell

[0105] Compared with Example 1, this comparative example differs in terms of resistance, formulation, and compaction density, as detailed in Table 1:

[0106] Table 1

[0107]

[0108] Test Example 1 Cycle Life Test

[0109] The battery cells of Example 1 and Comparative Example 1 were packaged in aluminum-plastic film, baked to remove moisture, and then injected with electrolyte to form lithium-ion batteries.

[0110] The preparation method of the electrolyte includes: mixing propylene carbonate, ethylene carbonate, dimethyl carbonate and ethyl methyl carbonate in a weight ratio of 1:1:0.5:1, and then adding LiPF6 to obtain the electrolyte, wherein the concentration of LiPF6 is 1 mol / L.

[0111] The cycle life of the lithium-ion batteries prepared above was compared. The cycle retention rate was tested at 45°C using the following method: charging mode was 3.0C-4.25V (cutoff 2.0C) to 2.0C-4.30V (cutoff 1.5C) to 1.5C-4.45V (cutoff 0.025C), and discharging mode was 0.7C discharge, with 600 cycles tested.

[0112] The results are as follows Figure 5 As shown, Example 1 maintained a capacity retention rate of 92.4% after 500 cycles, while Comparative Example 1 maintained a capacity retention rate of 84.2% after 500 cycles. It is evident that Example 1 exhibits an 8.2% higher capacity retention rate after 500 cycles than Comparative Example 1, and shows no cycle failure.

[0113] Example 2 and Comparative Example 2: Winded Battery Cell

[0114] Example 2 and Comparative Example 2 differ in positive and negative electrode resistance, formulation, porosity and compaction density, as detailed in Table 2. The electrode preparation method is the same as that in Example 1.

[0115] Example 2 and Comparative Example 2, tested according to the method of Test Example 1, showed a capacity retention rate of 88.5% after 500 cycles at 45°C, while Comparative Example 2 showed a capacity retention rate of 82.8% after 500 cycles. It is evident that Example 2 exhibits a 5.7% higher capacity retention rate than Comparative Example 1 after 500 cycles, and shows no cycle failure.

[0116] Table 2

[0117]

[0118] Example 3 and Comparative Example 3: Winded Battery Cell

[0119] There are differences between Example 3 and Comparative Example 3 in terms of positive and negative electrode resistance, formulation, positive and negative electrode conductive agent tube wall length, and negative electrode graphite orientation, as detailed in Table 3. The electrode preparation method is the same as that in Example 1.

[0120] Example 3 and Comparative Example 3, tested according to the method of Test Example 1, showed a capacity retention rate of 85.2% after 500 cycles at 45°C, while Comparative Example 1 showed a capacity retention rate of 80.6% after 500 cycles. It is evident that Example 3 exhibits a 4.6% higher capacity retention rate than Comparative Example 3 after 500 cycles, and shows no cycle failure.

[0121] Table 3

[0122]

[0123] The above description is only a preferred embodiment of the present invention. It should be noted that for those skilled in the art, several improvements and modifications can be made without departing from the principle of the present invention, and these improvements and modifications should also be considered within the scope of protection of the present invention.

Claims

1. A wound battery cell, characterized in that, The wound battery cell includes a wound negative electrode and a wound positive electrode. The negative electrode sheet includes a first negative electrode active coating, a current collector, and a second negative electrode active coating arranged sequentially; the first negative electrode active coating is disposed on the surface of the current collector near the center of the curl; the second negative electrode active coating is disposed on the surface of the current collector away from the center of the curl; the resistance of the first negative electrode active coating is greater than the resistance of the second negative electrode active coating; And / or, the positive electrode sheet includes a first positive electrode active coating, a current collector, and a second positive electrode active coating disposed sequentially; the first positive electrode active coating is disposed on the surface of the current collector near the center of the curl; the second positive electrode active coating is disposed on the surface of the current collector away from the center of the curl; the resistance of the first positive electrode active coating is greater than the resistance of the second positive electrode active coating; The resistance of the first negative electrode active coating is 1~10Ω, and the resistance of the second negative electrode active coating is 0.1~5Ω; The resistance of the first positive electrode active coating is 500~3000Ω, and the resistance of the second positive electrode active coating is 100~1000Ω.

2. The wound battery cell according to claim 1, characterized in that, The resistance of the first negative electrode active coating is greater than that of the second negative electrode active coating, and this resistance is adjusted by at least one of the following methods: (1) The porosity of the first negative electrode active coating is less than that of the second negative electrode active coating; (2) The conductive agent content of the first negative electrode active coating is less than that of the second negative electrode active coating; (3) The conductive agents of the first negative electrode active coating and the second negative electrode active coating are both tubular conductive agents, and the tube wall length of the conductive agent of the first negative electrode active coating is less than the tube wall length of the conductive agent of the second negative electrode active coating. (4) The graphite orientation index of the first negative electrode active coating is greater than that of the second negative electrode active coating. (5) The compaction density of the first negative electrode active coating is greater than that of the second negative electrode active coating; The resistance of the first positive electrode active coating is greater than that of the second positive electrode active coating, and this resistance is adjusted by at least one of the following methods: (1) The porosity of the first positive electrode active coating is less than that of the second positive electrode active coating; (2) The conductive agent content of the first positive electrode active coating is less than that of the second positive electrode active coating; (3) The conductive agents of the first positive electrode active coating and the second positive electrode active coating are both tubular conductive agents, and the tube wall length of the conductive agent of the first positive electrode active coating is less than the tube wall length of the conductive agent of the second positive electrode active coating. (4) The compaction density of the first positive electrode active coating is greater than that of the second positive electrode active coating.

3. The wound battery cell according to claim 1, characterized in that, The components of the first negative electrode active coating or the second negative electrode active coating include: Negative electrode active material: 75~99.8 wt%; Conductive agent 0.5~15 wt% Adhesive 0.5~15 wt%.

4. The wound battery cell according to claim 3, characterized in that, In the first negative electrode active coating or the second negative electrode active coating, The negative electrode active material is independently selected from one or more of artificial graphite, natural graphite, mesophase carbon microspheres, soft carbon, and hard carbon; The conductive agent is independently selected from one or more of the following: conductive carbon black, carbon fiber, Ketjen black, acetylene black, carbon nanotubes, graphene, Ketjen black, conductive graphite, conductive carbon fiber, carbon nanotubes, metal powder, and carbon fiber. The adhesive is independently selected from one or more of styrene-butadiene rubber, polyacrylic acid, polyurethane, polyvinyl alcohol, polyvinylidene fluoride, and copolymers of vinylidene fluoride-fluorinated olefins.

5. The wound battery cell according to claim 1, characterized in that, The components of the first positive electrode active coating or the second positive electrode active coating include: Positive electrode active material 75~99.8 wt% Conductive agent 0.5~15 wt% Adhesive 0.5~15 wt%.

6. The wound battery cell according to claim 5, characterized in that, In the first positive electrode active coating or the second positive electrode active coating, The positive electrode active material is independently selected from one or more of nickel cobalt manganese, lithium iron phosphate, nickel cobalt aluminum, lithium cobalt oxide, and lithium manganese oxide; The conductive agent is independently selected from one or more of the following: conductive carbon black, Ketjen black, conductive fiber, conductive polymer, acetylene black, carbon nanotubes, graphene, flake graphite, conductive oxide, and metal particles. The adhesive is independently selected from one or more of the following: polyvinylidene fluoride, copolymer of polyvinylidene fluoride and hexafluoropropylene, polyamide, polyacrylonitrile, polyacrylate, polyacrylic acid, polyacrylate, polyvinylpyrrolidone, polyvinyl ether, polymethyl methacrylate, polytetrafluoroethylene, polyhexafluoropropylene, and styrene-butadiene rubber.

7. The wound battery cell according to claim 1, characterized in that, The thickness of the first negative electrode active coating, the second negative electrode active coating, the first positive electrode active coating, or the second positive electrode active coating is 20~75μm.

8. The wound cell according to any one of claims 1-7, characterized in that, The wound battery cell also includes one or more of the following: positive tab, negative tab, and separator.

9. A battery, characterized in that, The battery comprises a wound cell as described in any one of claims 1-8.

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