Pole piece, battery cell and lithium ion battery for lithium ion battery

Abstract

The utility model discloses a kind of pole piece, electric core and lithium ion battery for lithium ion battery, the pole piece for the lithium ion battery includes current collector, the surface of current collector is provided with active material layer, current collector and active material layer are provided with elastic layer, and elastic layer is along the side edge of current collector and is arranged. By the side edge between current collector and active material layer and is arranged elastic layer, to improve the mechanical distribution of pole piece in laser cleaning slot position process. Specifically, as buffer medium, elastic layer can reduce the thermal stress concentration phenomenon generated in laser cleaning process, so that the stress around the lug welding slot of subsequent processing is effectively dispersed and alleviated, so as to improve the toughness and anti-cracking ability of current collector and active material layer interface.

Description

Technical Field

[0001] This application relates to the field of electrochemical energy storage technology, and in particular to an electrode, a cell, and a lithium-ion battery for use in lithium-ion batteries. Background Technology

[0002] In the manufacturing process of lithium-ion batteries, the electrode sheet, as the core component of the battery, needs to undergo multiple processes such as coating, drying, rolling, and slitting. Among them, electrode tab welding is a critical step in the battery assembly process. It is necessary to clean specific areas on the electrode sheet to form welding grooves and ensure a good electrical connection between the electrode tab and the electrode sheet.

[0003] In existing technologies, laser cleaning technology is typically used to directly clean the electrode surface locally in order to create grooves for tab welding on the electrode. Laser cleaning uses a high-energy laser beam to irradiate the electrode surface, causing the active material layer to vaporize or decompose instantaneously, thereby forming clean grooves on the electrode that expose the current collector. However, due to the dense structure and strong adhesion of ternary materials (such as NCM, NCA, etc.), a single laser cleaning is often insufficient to completely remove the active material layer. Therefore, high-power lasers and multiple repeated cleaning processes are required to achieve the desired level of cleanliness.

[0004] The above-mentioned technical solution has obvious defects. During multiple laser cleaning processes, the repeated irradiation by high-energy lasers will generate thermal stress concentration around the tank, resulting in a significant tension difference between the tank and adjacent electrode areas. When the cleaned electrode enters the rolling process, due to the uneven tension between the tank area and the edge electrode, the electrode is prone to stress concentration at the edge of the tank, which can lead to edge cracking or even strip breakage. Utility Model Content

[0005] The main purpose of this application is to propose an electrode for lithium-ion batteries, which aims to reduce the problem of edge cracking or even breakage after the electrode slots are opened.

[0006] To achieve the above objectives, this application proposes an electrode for lithium-ion batteries. The electrode for lithium-ion batteries includes a current collector, an active material layer disposed on the surface of the current collector, and an elastic layer disposed between the current collector and the active material layer, the elastic layer being disposed along one edge of the current collector.

[0007] In some embodiments, the length of the elastic layer is the same as the length of the current collector.

[0008] In some embodiments, the thickness of the elastic layer is H1, the thickness of the active material layer is H2, and the following relationship is satisfied:

[0009] H1≤0.3*H2.

[0010] In some embodiments, the thickness of the elastic layer is H1, and satisfies the following relationship:

[0011] 1μm≤H1≤10μm.

[0012] In some embodiments, the width of the elastic layer is W1, the width of the active material layer is W2, and the following relationship is satisfied:

[0013] W1≤0.1*W2.

[0014] In some embodiments, the width of the elastic layer is W1, and satisfies the following relationship:

[0015] 5mm≤W1≤50mm.

[0016] In some embodiments, the current collector has a first surface and a second surface opposite each other in its thickness direction, and both the first surface and the second surface are provided with the elastic layer and the active material layer.

[0017] In some embodiments, the material of the elastic layer is selected from any one of polyvinylidene fluoride, sodium carboxymethyl cellulose and styrene-butadiene rubber, polyurethane, and polyimide.

[0018] This application further proposes a battery cell, including a separator and an electrode sheet stacked and wound with the separator, wherein the electrode sheet is the same as the electrode sheet for lithium-ion batteries described in the foregoing embodiments.

[0019] This application further proposes a lithium-ion battery, including the cell of the aforementioned embodiment.

[0020] This application's technical solution improves the mechanical distribution of the electrode sheet during the laser cleaning process by setting an elastic layer on one side edge between the current collector and the active material layer. Specifically, the elastic layer acts as a buffer medium, reducing the thermal stress concentration generated during laser cleaning, effectively dispersing and alleviating stress around the cleaning area, thereby improving the toughness and crack resistance of the interface between the current collector and the active material layer. When the cleaned electrode sheet enters the rolling process, the elastic layer can coordinate the tension difference between the cleaning area and adjacent electrode sheet areas, avoiding edge cracking and strip breakage caused by stress concentration. This effectively solves the technical problem of edge damage to the electrode sheet after multiple laser cleanings, improving the pass rate and production efficiency of the battery cell production process. Attached Figure Description

[0021] Figure 1 This is a schematic diagram of the cross-section along the length of an embodiment of the electrode sheet used in a lithium-ion battery according to this application;

[0022] Figure 2This is a schematic diagram of the cross-section along the width direction of an embodiment of the electrode sheet used in a lithium-ion battery according to this application;

[0023] Figure 3 This is a top view of an embodiment of the electrode used in a lithium-ion battery according to this application. Attached image description:

[0025] 10. Electrode; 100. Current collector; 101. Active material layer; 102. Elastic layer;

[0026] 100a, First side; 100b, Second side; F, Slot. Detailed Implementation

[0027] The solutions in the embodiments of this application will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only a part of the embodiments in this application, and not all of the embodiments. Based on the embodiments in this application, all other embodiments obtained by those of ordinary skill in the art without creative effort are within the scope of protection of this application.

[0028] It should be noted that all directional indicators (such as up, down, left, right, front, back, etc.) in the embodiments of this application are only used to explain the relative positional relationship and movement of each component in a certain specific posture (as shown in the figure). If the specific posture changes, the directional indicator will also change accordingly.

[0029] It should also be noted that when a component is described as "fixed to" or "set on" another component, it can be directly on the other component or there may be an intervening component present. When a component is described as "connected to" another component, it can be directly connected to the other component or there may be an intervening component present.

[0030] Furthermore, the use of terms such as "first" and "second" in this application is for descriptive purposes only and should not be construed as indicating or implying their relative importance or implicitly specifying the number of technical features indicated. Therefore, a feature defined as "first" or "second" may explicitly or implicitly include at least one of that feature. Additionally, the technical solutions of the various embodiments can be combined with each other, but only on the basis of being achievable by those skilled in the art. When the combination of technical solutions is contradictory or impossible to implement, such a combination of technical solutions should be considered non-existent and not within the scope of protection claimed in this application.

[0031] In the production process of lithium-ion battery electrodes, after the current collector is coated with the active material layer, it needs to be laser-cleaned to create grooves for welding the tabs. However, related technologies often require multiple laser cleaning processes, and repeated irradiation by high-energy lasers can easily generate thermal stress concentration around the grooves. When the cleaned electrode enters the rolling process, the uneven tension between the grooved area and adjacent electrode areas can cause stress concentration at the edge of the groove, leading to edge cracking or even strip breakage. To solve the above problems, this embodiment proposes an electrode for lithium-ion batteries that improves the mechanical distribution of the electrode during the laser cleaning groove process by setting an elastic layer on one edge between the current collector and the active material layer. Specifically, the elastic layer acts as a buffer medium, reducing the thermal stress concentration generated during laser cleaning, effectively dispersing and alleviating the stress around the grooves, thereby improving the toughness and crack resistance of the interface between the current collector and the active material layer. (See also...) Figure 1 and Figure 2 This utility model embodiment proposes an electrode 10 for a lithium-ion battery. The electrode 10 for a lithium-ion battery includes a current collector 100. An active material layer 101 is disposed on the surface of the current collector 100. An elastic layer 102 is disposed between the current collector 100 and the active material layer 101. The elastic layer 102 is disposed along one edge of the current collector 100.

[0032] In this embodiment, the electrode 10 can be either a positive electrode or a negative electrode. Specifically, in a battery cell, the elastic layer 102 can be provided only on the current collector 100 of the positive electrode, or the elastic layer 102 can be provided on both the positive and negative electrodes of the same battery cell to further enhance the stability of the overall structure. It should be noted that in this embodiment, the elastic layer 102 can be provided on both surfaces of the current collector 100 to form a double-sided sheet, mainly used for the inner winding of the battery cell; of course, the elastic layer 102 and the active material layer 101 can also be provided on only one surface of the current collector 100 to form a single-sided sheet, mainly used for the outer winding of the battery cell, thereby adapting to different production needs. In this embodiment, the elastic layer 102 can be made of materials such as silicone rubber, polyurethane, or thermoplastic elastomers to ensure that it has good cushioning and adhesion. The current collector 100 can be made of aluminum foil or copper foil. When the electrode 10 is a positive electrode, the active material layer 101 can be made of lithium cobalt oxide, lithium iron phosphate, or ternary materials. When the electrode 10 is a negative electrode, the active material layer 101 can be made of graphite, silicon-based materials, or hard carbon. The elastic layer 102 is provided along one edge of the current collector 100, which is the preset area of ​​the groove F for subsequent welding of the electrode tab, thereby accurately positioning the buffering effect of the elastic layer 102.

[0033] The preparation process of this embodiment is as follows: An elastic layer 102 is formed on the surface of the current collector 100, and the elastic layer 102 is set on one side edge of the current collector 100, which corresponds to the position where the subsequent groove F is opened. Then, an active material layer 101 is coated on the surface of the current collector 100, and the active material layer 101 covers the other area of ​​the current collector 100 and the surface of the elastic layer 102 to form a complete coating structure. Next, a laser cleaning process is performed, in which the groove F is repeatedly cleaned on one side edge of the electrode 10 using a laser. It should be noted that the groove F is formed within the range of the elastic layer 102, and the width of the groove F does not exceed the width of the elastic layer 102, thereby ensuring that the elastic layer 102 completely surrounds the groove F area and avoids thermal stress overflow. In the subsequent rolling process, since the elastic layer 102 has deformation recovery properties, it can act as a flexible buffer layer to coordinate the tension difference between the groove F area and the adjacent electrode 10 area, effectively alleviating the local stress concentration caused by uneven thickness during the rolling process, ensuring that the electrode 10 deforms uniformly under high pressure and avoiding edge warping or tearing.

[0034] The technical solution of this application improves the mechanical distribution of the electrode 10 in the laser cleaning tank F process by setting an elastic layer 102 on one side edge between the current collector 100 and the active material layer 101. Specifically, the elastic layer 102 acts as a buffer medium, reducing the thermal stress concentration generated during laser cleaning, effectively dispersing and alleviating the stress around the tank F, thereby improving the toughness and crack resistance of the interface between the current collector 100 and the active material layer 101. When the cleaned electrode 10 enters the rolling process, the elastic layer 102 can coordinate the tension difference between the tank F area and the adjacent electrode 10 area, avoiding edge cracking and strip breakage caused by stress concentration. This effectively solves the technical problem that the electrode 10 is prone to edge damage after multiple laser cleanings, improving the pass rate and production efficiency of the battery cell production process.

[0035] Continue reading Figure 1 In this embodiment, the length of the elastic layer 102 is the same as the length of the current collector 100. Specifically, the elastic layer 102 extends along the length of the current collector 100, covering the entire preset tank area F, ensuring that the thermal stress generated during the laser cleaning process is uniformly dispersed and alleviated throughout the entire length of the current collector 100. Thus, by covering the entire length of the elastic layer 102, the thermal stress distribution in the laser cleaning tank area F process can be effectively coordinated, improving the toughness of the interface between the current collector 100 and the active material layer 101. In the subsequent rolling process, the elastic layer 102 can further balance the tension difference between the tank area F and adjacent areas, significantly reducing the risk of edge cracking and strip breakage, thereby improving the stability of electrode sheet 10 processing and the pass rate of cell production.

[0036] See Figure 2In this embodiment, the thickness of the elastic layer 102 is H1, and the thickness of the active material layer 101 is H2, and they satisfy the following relationship:

[0037] H1≤0.3*H2.

[0038] In this embodiment, the thickness H1 of the elastic layer 102 does not exceed 30% of the total thickness H2 of the active material layer 101 (single-sided) to avoid the elastic layer 102 occupying too much space in the active material layer 101, thereby providing a buffering effect while also considering battery capacity. For example, when the thickness H2 of the active material layer 101 is 100 μm, according to the formula H1≤0.3×H2, the thickness H1 of the elastic layer 102 is ≤30 μm; as another example, when H2 is 150 μm, H1≤45 μm; and as yet another example, when H2 is 200 μm, H1≤60 μm. This thickness design ensures that the elastic layer 102 effectively disperses thermal stress and tension differences during laser cleaning and rolling processes, while not significantly reducing the energy density of the electrode 10, thus improving the overall performance and production stability of the cell.

[0039] In a preferred embodiment, the thickness of the elastic layer 102 is H1, and it satisfies the following relationship:

[0040] 1μm≤H1≤10μm.

[0041] In this embodiment, the thickness H1 of the elastic layer 102 can be 1μm, 2μm, 3μm, 4μm, 5μm, 6μm, 7μm, 8μm, 9μm, or 10μm. This thickness range is designed to fully consider the multiple functional requirements of the elastic layer 102 in the production of the lithium-ion battery electrode 10. On the one hand, it ensures that the elastic layer 102 has sufficient deformation buffering capacity to effectively absorb and disperse the thermal stress generated in the laser cleaning tank F process, preventing microcracks from forming at the interface between the current collector 100 and the active material layer 101 due to repeated high-temperature action. On the other hand, this range limits the volume occupied by the elastic layer 102, preventing excessive thickening that would increase the overall thickness of the electrode 10, thereby maintaining the energy density and volumetric efficiency of the battery. Specifically, when the thickness H1 of the elastic layer 102 is 1μm-3μm, it is suitable for the production of high-precision thin electrode sheets 10, with moderate buffering effect, suitable for cell designs with extremely high energy density requirements, and can minimize interference with the space of the active material layer 101. When the thickness H1 of the elastic layer 102 is 4μm-6μm, it provides stronger thermal stress relief capability, suitable for standard medium-thick electrode sheets 10, balancing buffering performance and production cost. When the thickness H1 of the elastic layer 102 is 7μm-10μm, it enhances the tension coordination effect in the rolling process, significantly reducing the risk of edge cracking, and is suitable for high-strength processing or long-size electrode sheets 10. This thickness selection can be flexibly adjusted according to the specific active material layer 101 thickness H2 (for example, combined with the aforementioned relationship H1≤0.3×H2), further optimizing the stability of the electrode sheet 10 in continuous production and the cycle life of the cell.

[0042] See Figure 3 In this embodiment, the width of the elastic layer 102 is W1, and the width of the active material layer 101 is W2, and they satisfy the following relationship:

[0043] W1≤0.1*W2.

[0044] In this embodiment, the width W1 of the elastic layer 102 does not exceed 10% of the width W2 of the active material layer 101 to avoid the elastic layer 102 occupying too much space of the active material layer 101, thereby providing lateral buffering while taking into account battery capacity and energy density. For example, when the width W2 of the active material layer 101 is 100mm, according to the formula W1≤0.1×W2, the width W1 of the elastic layer 102 is ≤10mm; as another example, when W2 is 200mm, W1≤20mm; and as yet another example, when W2 is 500mm, W1≤50mm. This ensures that the elastic layer 102 effectively covers the preset area in the laser cleaning tank F process to disperse thermal stress, while minimizing the impact on the overall width of the electrode 10, thus improving the cell's volume utilization and production adaptability.

[0045] In a preferred embodiment, the width of the elastic layer 102 is W1, and satisfies the following relationship:

[0046] 5mm≤W1≤50mm.

[0047] In this embodiment, the width W1 of the elastic layer 102 can be 5mm, 6mm, 7mm, 8mm, 9mm, 10mm, 11mm, 12mm, 13mm, 14mm, 15mm, 16mm, 17mm, 18mm, 19mm, 20mm, 21mm, 22mm, 23mm, 24mm, 25mm, 26mm, 27mm, 28mm, 29mm, 30mm, 31mm, 32mm, 33mm, 34mm, 35mm, 36mm, 37mm, 38mm, 39mm, 40mm, 41mm, 42mm, 43mm, 44mm, 45mm, 46mm, 47mm, 48mm, 49mm, or 50mm. The width range is designed to fully consider the lateral buffering function of the elastic layer 102 in the production of lithium-ion battery electrode 10 and its compatibility with the overall structure. This ensures that the width of the elastic layer 102 is sufficient to cover the preset slot F area, providing lateral thermal stress and tension dispersion capabilities, and avoiding lateral stress concentration and microcrack propagation caused by high-energy laser irradiation during laser cleaning. On the other hand, this range limits the lateral expansion of the elastic layer 102, preventing it from excessively occupying the coating space of the active material layer 101, thereby maintaining the width utilization rate of the electrode 10 and the volumetric energy density of the battery. Specifically, when W1 is 5mm-15mm, it is suitable for narrow-width electrode sheets 10 or high-precision processing, providing precise buffering with minimal interference to the active material layer 101. This is suitable for small cells or space-sensitive winding designs, effectively mitigating localized thermal damage at the edge of the slot F without sacrificing capacity. When W1 is 16mm-30mm, it provides more comprehensive lateral protection, enhancing the uniform stress distribution during repeated laser cleaning. This is suitable for standard medium-width electrode sheets 10, balancing buffering performance, production compatibility, and cost control. When W1 is 31mm-50mm, it further expands the coverage of the elastic layer 102, significantly improving the tension coordination effect on the long slot F area during the rolling process, reducing the risk of edge warping and strip breakage. This is suitable for the production of large-size or high-strength electrode sheets 10. This width selection can be flexibly adjusted according to the width W2 of the active material layer 101 (e.g., combined with the aforementioned relationship W1≤0.1×W2), further optimizing the stability of the electrode sheet 10 during continuous winding and assembly processes, as well as the cycle performance and safety of the cell.

[0048] See Figure 2 In this embodiment, the current collector 100 has a first surface 100a and a second surface 100b opposite each other in its thickness direction. Both the first surface 100a and the second surface 100b are provided with an elastic layer 102 and an active material layer 101.

[0049] Specifically, the electrode 10 adopts a double-sided coating structure design, meaning that an elastic layer 102 is provided on both surfaces (first surface 100a and second surface 100b) of the current collector 100. The elastic layers 102 are located at one edge of the first surface 100a and the second surface 100b, respectively, and the elastic layers 102 on the two surfaces are aligned facing each other in the thickness direction to form a symmetrical buffer area. Subsequently, an active material layer 101 is coated on the surface of the elastic layers 102 on the first surface 100a and the second surface 100b, as well as the remaining area of ​​the current collector 100, thereby forming a complete double-sided electrode structure. This design ensures that the thermal stress on both sides of the electrode 10 is simultaneously dispersed during the laser cleaning tank F process, while also improving the overall mechanical stability.

[0050] To further illustrate the fabrication and application of this double-sided sheet structure, the elastic layer 102 in this embodiment can be made of a material with high adhesion and flexibility, such as silicone rubber or polyurethane, to ensure a strong interface bond between it and the current collector 100 (such as aluminum foil or copper foil). The elastic layers 102 positioned opposite each other in the thickness direction can support each other, forming a buffer channel that extends through the entire thickness of the current collector 100. During laser cleaning, laser irradiation in the preset area of ​​the slot F will simultaneously act on the interior of the elastic layer 102 on both the first side 100a and the second side 100b, preventing warping deformation caused by unilateral thermal stress. The active material layer 101 covers the surface of the elastic layer 102 and the remaining areas, forming a uniform coating thickness to maintain the battery's capacity balance. This double-sided sheet is mainly suitable for the inner winding process of battery cells. During winding, the symmetrical elastic layers 102 on both sides can effectively coordinate internal stress and external tension, reducing the risk of edge cracking due to bending, while also improving the compatibility of the electrode 10 in high-density battery cells.

[0051] The symmetrical buffering on both sides of the elastic layer 102 not only reduces the heat accumulation effect under multiple laser cleaning operations, but also takes into account the volumetric energy density and cycle life of the battery, making it suitable for the production needs of high-power or long-life lithium-ion batteries. The specific parameters of this structure can be fine-tuned by combining the aforementioned thickness relationship (H1≤0.3×H2) and width relationship (W1≤0.1×W2) to adapt to cell designs of different specifications.

[0052] In this step, the material of the elastic layer 102 is selected from any one of polyvinylidene fluoride, sodium carboxymethyl cellulose and styrene-butadiene rubber, polyurethane, and polyimide. Specifically, this material selection ensures that the elastic layer 102 has excellent flexibility, adhesion, and heat resistance, effectively buffering the thermal stress during the laser cleaning process and the tension differences during the rolling process, while also being highly compatible with the current collector 100 and the active material layer 101, avoiding interface delamination.

[0053] This application further proposes a battery cell, including a separator and an electrode 10 laminated and wound with the separator. The electrode 10 is the same as the electrode 10 for lithium-ion batteries described in the foregoing embodiments. The specific structure of the electrode 10 for lithium-ion batteries is as described in the above embodiments. Since this battery cell adopts all the technical solutions of all the above embodiments, it has at least all the technical effects brought about by the technical solutions of the above embodiments, and will not be described in detail here.

[0054] To further illustrate the optimization of this cell structure, in this embodiment, during the laser cleaning process at slot F, the electrode 10 utilizes an elastic layer 102 to effectively reduce thermal stress concentration. This disperses and alleviates the stress around slot F, thereby improving the toughness and crack resistance of the interface between the current collector 100 and the active material layer 101, and preventing edge damage of the electrode 10 from interfering with the winding process. When the electrode 10 enters the rolling process, the elastic layer 102 coordinates the tension difference between the slot F area and adjacent areas, preventing edge cracking and strip breakage, ensuring that the electrode 10 maintains structural integrity when stacked and wound with the separator. This design not only improves the yield and efficiency of the cell production process but also enhances the overall mechanical stability and cycle life of the cell, making it suitable for high-energy-density lithium-ion battery applications.

[0055] In practical applications, the winding structure of this battery cell benefits from the symmetrical arrangement of the elastic layer 102 on both sides (if a double-sided design is adopted), further balancing the stress distribution of the inner and outer rings and preventing the propagation of microcracks caused by bending during winding. Simultaneously, the thickness (1μm≤H1≤10μm) and width (5mm≤W1≤50mm) range of the elastic layer 102 ensures minimal interference in the cell thickness direction, balancing battery capacity and volumetric efficiency. By inheriting the technological advantages of the electrode 10, this battery cell effectively solves the edge damage problem that easily occurs in traditional battery cells during high-intensity processing, improving the reliability and market competitiveness of the battery cell.

[0056] This application further proposes a lithium-ion battery including the cell of the aforementioned embodiment. Specifically, the lithium-ion battery forms a complete battery structure by integrating the cell, wherein the elastic layer 102 of the electrode 10 in the cell acts as a buffer medium, effectively reducing thermal stress concentration and tension differences during laser cleaning and rolling processes, and avoiding edge cracking and strip breakage.

[0057] The above description is only a part or preferred embodiment of this application. Neither the text nor the drawings should limit the scope of protection of this application. All equivalent structural transformations made using the content of this application's specification and drawings under the overall concept of this application, or direct / indirect applications in other related technical fields, are included within the scope of protection of this application.

Claims

1. An electrode for lithium-ion batteries, characterized in that, The device includes a current collector, the surface of which is provided with an active material layer, and an elastic layer is provided between the current collector and the active material layer, the elastic layer being disposed along one edge of the current collector.

2. The electrode for a lithium-ion battery according to claim 1, characterized in that, The length of the elastic layer is the same as the length of the current collector.

3. The electrode for a lithium-ion battery according to claim 2, characterized in that, The thickness of the elastic layer is H1, and the thickness of the active material layer is H2, and they satisfy the following relationship: H1≤0.3*H2.

4. The electrode for a lithium-ion battery according to claim 3, characterized in that, The thickness of the elastic layer is H1, and it satisfies the following relationship: 1μm≤H1≤10μm.

5. The electrode for a lithium-ion battery according to claim 2 or 4, characterized in that, The width of the elastic layer is W1, and the width of the active material layer is W2, and they satisfy the following relationship: W1≤0.1*W2.

6. The electrode for a lithium-ion battery according to claim 5, characterized in that, The width of the elastic layer is W1, and it satisfies the following relationship: 5mm≤W1≤50mm.

7. The electrode for a lithium-ion battery according to claim 5, characterized in that, The current collector has a first surface and a second surface opposite each other in its thickness direction, and both the first surface and the second surface are provided with the elastic layer and the active material layer.

8. The electrode for a lithium-ion battery according to claim 1, characterized in that, The material of the elastic layer is selected from any one of polyvinylidene fluoride, sodium carboxymethyl cellulose and styrene-butadiene rubber, polyurethane, and polyimide.

9. A battery cell, characterized in that, It includes a separator and an electrode layered and wound with the separator, the electrode being the electrode for a lithium-ion battery as described in any one of claims 1 to 8.

10. A lithium-ion battery, characterized in that, Includes the battery cell described in claim 9.

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