Anode strip and battery cell

Abstract

The utility model provides an anode strip and a battery cell. The anode strip has a thickness direction, a length direction and a width direction which are mutually vertical in pairs. The anode strip comprises a base layer, a first active substance and a second active substance; in the thickness direction, the base layer comprises a first side and a second side which are opposite, and in the length direction, at least one end of the second side is provided with a local coating area; the first active material layer covers the first side; a second active material layer covers the area outside the second side local coating area, and a part of the local coating area is covered with the second active material layer. The battery cell comprises a cathode piece, a diaphragm and the anode piece, the cathode piece is located on one side of the diaphragm, and the anode piece is located on one side, away from the cathode piece, of the diaphragm in the thickness direction. According to the anode strip and the battery cell, the winding and folding phenomenon can be effectively improved.

Description

Technical Field

[0001] The present application relates to the field of battery technology, and in particular to an anode sheet and a battery cell. Background Art

[0002] The anode sheet includes a double-sided coating area and a single-sided coating area. The single-sided coating area is usually located at the end of the anode sheet. The side of the single-sided coating area coated with active material corresponds to the cathode sheet to improve lithium deposition. The side not coated with active material can reduce space occupation and improve the energy density of the wound battery cell. However, because one side of the single-sided coating area is coated with active material and the other side is not coated with active material, the stress on both sides of the single-sided coating area is unbalanced. Under the action of stress, the side coated with active material tends to bend toward the side not coated with active material, resulting in frequent electrode sheet folding, which is not conducive to the winding production of the battery cell. Utility Model Content

[0003] The present application aims to solve at least one of the technical problems existing in the prior art. To this end, the present application proposes an anode sheet that can effectively improve the phenomenon of electrode sheet folding.

[0004] The present application also provides a battery cell having the above-mentioned anode sheet.

[0005] According to the embodiment of the present application, the anode sheet has a thickness direction, a length direction and a width direction that are perpendicular to each other. The anode sheet includes a base layer, a first active material layer and a second active material layer;

[0006] The base layer includes a first side and a second side opposite to each other in the thickness direction, and at least one end of the second side is provided with a local coating area in the length direction;

[0007] A first active material layer covers the first side;

[0008] An area outside the partially coated region on the second side is covered with the second active material layer, and a portion of the partially coated region is covered with the second active material layer.

[0009] The anode sheet according to the embodiment of the present application has at least the following beneficial effects: along the thickness direction, the area of ​​the first active material layer projected by the localized coating area is positioned toward the cathode sheet, ensuring that the active materials on the anode sheet and the cathode sheet surfaces face each other, thereby improving lithium deposition. Compared to a case where the second active material layer completely covers the localized coating area, the second active material covering a portion of the localized coating area helps reduce the space occupied by the anode sheet and also prevents the anode sheet from bending from the first side to the second side, thereby reducing the phenomenon of the anode sheet buckling.

[0010] According to some embodiments of the present application, the first active material layer includes a first main coating area and a skived coating area, the first main coating area is connected to the skived coating area, and along the thickness direction, the thickness of the skived coating area is less than the thickness of the first main coating area, and the skived coating area corresponds to the position of the second active material layer covering the local coating area.

[0011] According to some embodiments of the present application, the second active material layer includes a gap coating area, the gap coating area is located in the local coating area, and the gap coating area covers a portion of the local coating area, the thickness of the gap coating area is a, the thickness of the thinned coating area is b, and the thickness of the first main coating area is c, wherein a+b=c.

[0012] According to some embodiments of the present application, along the thickness direction, the thickness of the skived coating area is b, and the thickness of the first main coating area is c, wherein the value range of b / c is 0.95 to 0.97.

[0013] According to some embodiments of the present application, the second active material layer includes a second main coating area and a gap coating area, the second main coating area covers the area outside the local coating area on the second side, the gap coating area covers a part of the local coating area, and the thickness of the gap coating area is less than the thickness of the second main coating area.

[0014] According to some embodiments of the present application, the gap coating area includes at least two coating stripes. Along the length direction, the coating stripes extend from the edge of the base layer to connect with the second main coating area, and along the width direction, the coating stripes are spaced apart.

[0015] According to some embodiments of the present application, along the width direction, the width of the coating stripe is d, and then 0 mm < d ≤ 5 mm.

[0016] According to some embodiments of the present application, the thickness of the gap coating area is 3 um-6 um.

[0017] According to some embodiments of the present application, the ratio of the thickness of the gap coating region to the thickness of the anode sheet is 0.03-0.05.

[0018] The battery cell according to an embodiment of the present application includes a cathode sheet, a separator, and the anode sheet of any of the above embodiments. Along the thickness direction, the separator is located between the anode sheet and the cathode sheet.

[0019] The battery cell according to the embodiment of the present application has at least the following beneficial effects: the use of the above-mentioned anode sheet can effectively alleviate the folding phenomenon of the end of the anode sheet during the battery cell winding operation, which is beneficial to improving the qualified rate of the battery cell and improving the structural stability of the battery cell.

[0020] Additional aspects and advantages of the present application will be given in part in the description below, and in part will become obvious from the description below, or will be learned through practice of the present application. BRIEF DESCRIPTION OF THE DRAWINGS

[0021] The present application is further described below with reference to the accompanying drawings and embodiments, wherein:

[0022] Figure 1 A top view of the anode sheet according to an embodiment of the present application;

[0023] Figure 2 for Figure 1 Cross-sectional view at AA in the middle;

[0024] Figure 3 This is a bottom view of the anode sheet according to an embodiment of the present application;

[0025] Figure 4 for Figure 1 Cross-sectional view at the middle BB;

[0026] Figure 5 This is a side view of the anode sheet according to an embodiment of the present application.

[0027] Reference numerals: base layer 100 , first side 110 , second side 120 , local coating area 130 , first local coating area 131 , second local coating area 132 , tab 140 ;

[0028] First active material layer 200, first main coating area 210, skived coating area 220;

[0029] Second active material layer 300 , second main coating area 310 , gap coating area 320 , and coating stripes 321 . DETAILED DESCRIPTION

[0030] The following describes in detail embodiments of the present application. Examples of the embodiments are shown in the accompanying drawings, wherein the same or similar reference numerals throughout represent the same or similar elements or elements having the same or similar functions. The embodiments described below with reference to the accompanying drawings are exemplary and are only used to explain the present application and are not to be construed as limiting the present application.

[0031] In the description of this application, it should be understood that descriptions involving orientations, such as up, down, front, back, left, right, etc., indicating orientations or positional relationships, are based on the orientations or positional relationships shown in the accompanying drawings. They are only for the convenience of describing this application and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation. Therefore, they cannot be understood as limitations on this application.

[0032] In the description of this application, "several" means more than one, "plurality" means two or more, "greater than," "less than," and "exceed" are understood to exclude the number itself, while "above," "below," and "within" are understood to include the number itself. The terms "first" and "second" are used solely to distinguish technical features and are not to be construed as indicating or implying relative importance, or as implicitly specifying the number or order of the technical features indicated.

[0033] In the description of this application, unless otherwise clearly defined, terms such as setting, installing, and connecting should be understood in a broad sense, and technicians in the relevant technical field can reasonably determine the specific meanings of the above terms in this application based on the specific content of the technical solution.

[0034] In the description of this application, reference to the terms "one embodiment," "some embodiments," "illustrative embodiments," "examples," "specific examples," or "some examples" means that the specific features, structures, materials, or characteristics described in conjunction with the embodiment or example are included in at least one embodiment or example of this application. In this specification, the schematic representations of the above terms do not necessarily refer to the same embodiment or example. Moreover, the specific features, structures, materials, or characteristics described can be combined in any appropriate manner in any one or more embodiments or examples.

[0035] The following describes the embodiments of the present application in conjunction with the accompanying drawings:

[0036] refer to Figures 1 to 5 According to the embodiment of the present application, the anode sheet has a thickness direction, a length direction and a width direction that are perpendicular to each other. The anode sheet includes a base layer 100, a first active material layer 200 and a second active material layer 300. Along the thickness direction, the base layer 100 includes a first side 110 and a second side 120 that are opposite to each other. Along the length direction, at least one end of the second side 120 is provided with a local coating area 130, the first active material layer 200 covers the first side 110, and the area outside the local coating area 130 in the second side 120 is covered with the second active material layer 300, and a part of the local coating area 130 is covered with the second active material layer 300. Compared with the local coating area 130 that is not coated with active material, the second active material layer 300 located in the local coating area 130 can prevent the end of the base layer 100 from bending from the first side 110 to the second side 120, so as to alleviate the curling and folding phenomenon of the end of the anode sheet and facilitate the winding production of the battery cell. In addition, in the present application, the second active material layer 300 only covers a portion of the local coating area 130. Compared with the method of fully coating the local coating area 130 with active material to resist the curling and folding of the anode sheet, it reduces the space occupied by the anode sheet and improves the volume energy density of the anode sheet.

[0037] Specifically, along the length direction, a partially coated area 130 is provided at one end of the second side 120. Along the thickness direction, the first active material layer 200 completely covers the first side 110, and the second active material layer 300 completely covers the area of ​​the second side 120 outside the partially coated area 130, and the second active material layer 300 also covers a portion of the locally coated area 130. When winding the battery cell, the local coating area 130 corresponds to the beginning or end of the anode sheet winding. For example, the local coating area 130 corresponds to the end of the anode sheet winding. At the end of the anode sheet, the first side 110 of the base layer 100 is arranged toward the cathode sheet, so that the local coating area 130 is located on the side of the base layer 100 away from the cathode sheet. The second active material layer 300 covering the local coating area 130 is used to locally thicken the anode sheet at the location of the local coating area 130, alleviate the problem of uneven stress distribution between the first side 110 and the second side 120 of the anode sheet tail end, and resist bending of the anode sheet tail end, and the second active material layer 300 does not need to cover the entire local coating area 130. Therefore, the anode sheet of the present application can take into account the continuity of the battery cell winding production and reduce the space occupied, which is beneficial to ensure that the battery cell formed by winding has a high volume energy density and quality.

[0038] refer to Figures 1 to 5 In other embodiments, along the length direction, the second side 120 includes a first partially coated area 131 and a second partially coated area 132. The first partially coated area 131 and the second partially coated area 132 are located at opposite ends of the second side 120, and the second active material layer 300 covers the area between the first partially coated area 131 and the second partially coated area 132 on the second side 120. The second active material layer 300 also covers a portion of the first partially coated area 131 and a portion of the second partially coated area 132. Along the thickness direction, the first side 110 is completely covered by the first active material layer 200. The second active material layer 300 located within the first partially coated area 131 and the second partially coated area 132 is used to improve the bending phenomenon at the opposite ends of the anode sheet along the length direction.

[0039] Specifically, the two opposing ends of the anode sheet along its length serve as the leading and trailing ends of the wound cell, respectively. The provision of the localized coating area 132 reduces the volume occupied by the anode sheet and ensures the relative placement of the active materials on the anode and cathode surfaces. Furthermore, the second active material layer 300 covers a portion of the localized coating area 130, further improving the bending of the anode sheet ends and preventing bending at the beginning and / or end of cell winding, which could result in cell failure.

[0040] It should be noted that along the length direction, the anode sheet has an intermediate region between its two ends. The first side 110 of the intermediate region is coated with the first active material layer 200, and the second side of the intermediate region is coated with the second active material layer 300. The intermediate region can be understood as the double-sided coating area of ​​the anode sheet, and the two end regions can be understood as the single-sided coating area of ​​the anode sheet. In addition, along the length direction, the opposite ends of the second side 120, the opposite ends of the base layer 100, and the opposite ends of the anode sheet all refer to the same location.

[0041] refer to Figures 1 to 4 The base layer 100 is also provided with a tab 140. The number of the tabs 140 can be multiple, and each tab 140 is connected to the same side edge of the base layer 100, which is beneficial to improving the current transmission capacity of the anode sheet, and further beneficial to improving the output power and charging speed of the battery cell.

[0042] refer to Figures 1 to 5 In some embodiments, the first active material layer 200 includes a first main coating area 210 and a skived coating area 220. The first main coating area 210 is connected to the skived coating area 220. Along the thickness direction, the thickness of the skived coating area 220 is less than the thickness of the first main coating area 210, and the skived coating area 220 corresponds to the position of the second active material layer 300 covering the local coating area 130. It can be understood that, along the thickness direction, the projections of the second active material layer 300 and the skived coating area 220 in the local coating area 130 are almost overlapping. The second active material layer 300 includes a gap coating area 320 for covering the local coating area 130. The sum of the thicknesses of the thinned coating area 220 and the gap coating area 320 is the first thickness, and the thickness of the first main coating area 210 is the second thickness. Compared with the anode sheet structure of the present application, the thinned coating area 220 is not provided, which is beneficial to reducing the difference between the first thickness and the second thickness, so that the thickness of the base layer 100 at the end along the length direction tends to be consistent, which is beneficial to improving the consistency of the anode sheet thickness, and thus beneficial to ensuring the performance of the battery cell.

[0043] Specifically, along the thickness direction, the shapes of the skived coating area 220 and the gap coating area 320 match. For example, both the skived coating area 220 and the gap coating area 320 can be rectangular, and the length and width of the two areas are equal. In addition, the positions of the skived coating area 220 and the gap coating area 320 correspond to each other to achieve the thickness superposition of the skived coating area 220 and the gap coating area 320. The corresponding positions of the two, that is, the projection of the first main coating area 210 along the thickness direction is located in the area within the local coating area 130 that is not covered by the gap coating area 320, to avoid excessive protrusion caused by the thickness superposition of the gap coating area 320 and the first main coating area 210. Therefore, along the length direction, the thickness of the end of the anode sheet is the sum of the first thickness and the thickness of the base layer 100, or the thickness of the end of the anode sheet is the sum of the second thickness and the thickness of the base layer 100. The sum of the thickness of the second active material layer 300 covering the second side 120 of the local coating area 130 is beneficial to further improve the consistency of the thickness of the end of the anode sheet.

[0044] It should be noted that the gap coating area 320 may include active materials in the shape of points, blocks, rectangles, etc., and the active materials between each point, block, rectangle, etc. may be distributed at intervals. Accordingly, the thinned coating area 220 may have multiple areas, which may be spaced apart from each other. The shape of the outer contour of the thinned coating area 220 is consistent with the shape inside the gap coating area 320, and the sizes of the two are also consistent.

[0045] refer to Figures 1 to 5 In some embodiments, the second active material layer 300 includes a gap coating area 320, which is located in the local coating area 130 and covers a portion of the local coating area 130. The thickness of the gap coating area 320 is a, the thickness of the skived coating area 220 is b, and the thickness of the first main coating area 210 is c. Then, a+b=c, that is, the sum of the thicknesses of the gap coating area 320 and the skived coating area 220 is equal to the thickness of the first main coating area 210 (the first thickness is equal to the second thickness). As a result, the thickness of the end portion of the anode sheet along the length direction is more uniform, and the bending of the end portion of the anode sheet can be prevented, thereby improving the bending phenomenon of the anode sheet.

[0046] It should be noted that along the length direction, the thickness of the ends of the anode sheet is thinner than that of the middle portion. The thickness of the ends of the anode sheet is the sum of the thicknesses of the first main coating area 210 and the base layer 100. The thickness of the middle portion of the anode sheet is the sum of the thicknesses of the second active material layer 300 covering the middle portion of the base layer 100, the base layer 100, and the first main coating area 210. During the winding operation, the thinner end of the anode sheet is easier to wind and bend as the leading end, and the thinner end of the anode sheet is easier to fit and close as the trailing end, which is beneficial to improving the compactness of the battery cell and reducing the volume of the battery cell.

[0047] refer to Figures 1 to 5In some embodiments, along the thickness direction, the thickness of the skimmed coating zone 220 is b, and the thickness of the first main coating zone 210 is c. The value of b / c ranges from 0.95 to 0.97, that is, the thickness of the skimmed coating zone 220 is 95% to 97% of the thickness of the first main coating zone 210. For example, the value of b / c can be 0.95, 0.96, 0.97, or any other value between 0.95 and 0.97. By defining an upper limit for b / c, the coating thickness of the gap coating zone 320 is guaranteed and the impact on the surface uniformity of the end of the anode sheet is reduced. By defining a lower limit for b / c, an excessively large thickness difference between the first main coating zone 210 and the skimmed coating zone 220 is avoided.

[0048] It should be noted that the thickness reduction of the skived coating area 220 is used to provide coating space for the gap coating area 320 to ensure the uniformity of the thickness of the end of the anode sheet. When b / c increases, the thickness difference between the first main coating area 210 and the skived coating area 220 decreases. When b / c decreases, the thickness difference between the first main coating area 210 and the skived coating area 220 increases. Limiting the value of b / c is beneficial to better balance the thickness of the gap coating area 320 and the thickness difference between the first main coating area 210 and the skived coating area 220.

[0049] refer to Figures 1 to 5 In some embodiments, the second active material layer 300 includes a second main coating area 310 and a gap coating area 320. The second main coating area 310 covers the area outside the local coating area 130 on the second side 120, and the gap coating area 320 covers a portion of the local coating area 130. The thickness of the gap coating area 320 is less than that of the second main coating area 310, which is beneficial to reducing the space occupied by the anode sheet and, in turn, beneficial to improving the volume energy density of the battery cell.

[0050] It should be noted that Figure 1 The dotted frame represents the range of the gap coating area 320 , and the dotted frame is distinguished from the cutting lines at AA and BB, that is, the dotted frame and the cutting lines represent different meanings.

[0051] refer to Figures 1 to 5 In some embodiments, the gap coating area 320 includes at least two coating stripes 321. Along the length direction, the coating stripes 321 extend from the edge of the base layer 100 to the second main coating area 310, and along the width direction, the coating stripes 321 are spaced apart. The intervals between the coating stripes 321 can be adjusted as needed. Each coating stripe 321 is located in the local coating area 130 to prevent the anode sheet from bending toward the side where the local coating area 130 is located. At the same time, the intervals between the coating stripes 321 can reduce the space occupied by the anode sheet and ensure the volume energy density of the battery cell.

[0052] Specifically, the gap coating area 320 includes two coating stripes 321. The coating stripes 321 can be rectangular. The length direction of the anode sheet is the length direction of the coating stripes 321, and the width direction of the anode sheet is the width direction of the coating stripes 321. The two coating stripes 321 extend from the edge of the base layer 100 in the length direction to the second main coating area 310. In the width direction, the edges of the two coating stripes 321 are flush with the edges of the base layer 100, and the area between the two coating stripes 321 is an empty foil area. The empty foil area is used to accommodate structures such as protective glue to reduce the space occupied by the anode sheet. In addition, the edge of the base layer 100 is less stable than the middle area. Placing the two coating stripes 321 at the edge can effectively prevent the bending of the anode sheet and reduce the space occupied and the amount of active material used.

[0053] It should be noted that the coating stripe 321 is connected to the second main coating area 310 , and the connection between the two is located at the boundary of the partial coating area 130 .

[0054] refer to Figures 1 to 5 In some embodiments, the width of the coating stripe 321 along the width direction is d, then 0mm<d≤5mm. On the basis of keeping the thickness of the coating stripe 321 unchanged, by limiting the upper limit of the width of the coating stripe 321, it is possible to avoid the coating stripe 321 being too wide and resulting in excessive space occupation. It is also possible to set a larger number of coating stripes 321 in the local coating area 130. The multiple coating stripes 321 can be more flexibly arranged in the local coating area 130, which is beneficial to optimizing the stress distribution in the local coating area 130. On the basis of ensuring that the anode sheet resists bending, the space occupied by the anode sheet is reduced.

[0055] Specifically, the width of the coating stripe 321 can be 1 mm, 2 mm, 3 mm, 4 mm, 5 mm or any other value in the range of 0 mm to 5 mm, or the value range of the width of the coating stripe 321 can be an interval value with any two values ​​of 1 mm, 2 mm, 3 mm, 4 mm and 5 mm as endpoint values, so as to further optimize the arrangement of the coating stripe 321 in the local coating area 130.

[0056] refer to Figures 1 to 5 In some embodiments, the thickness of the gap coating area 320 is 3um-6um. The upper limit of the thickness of the gap coating area 320 is defined to avoid the thickness of the gap coating area 320 being greater than the thickness of the second main coating area 310 and causing local bulges. The lower limit of the thickness of the gap coating area 320 is defined to avoid the thickness of the gap coating area 320 being too thin and difficult to resist the stress difference between the first side 110 and the second side 120. Therefore, by limiting the thickness of the gap coating area 320, the bending resistance of the anode sheet can be guaranteed and it helps to reduce space occupancy.

[0057] For example, the thickness of the gap coating area 320 can be any value among 3um, 4um, 5um and 6um, or the thickness of the gap coating area 320 can be an interval value with any two values ​​of 3um, 4um, 5um and 6um as endpoint values, which is beneficial to further optimize the thickness of the gap coating area 320, so as to better balance the reduction of the space occupied by the gap coating area 320 and the bending resistance of the anode sheet, and reduce the space occupied by the anode sheet while ensuring that the anode sheet can resist bending.

[0058] refer to Figures 1 to 5 In some embodiments, the ratio of the thickness of the gap coating area 320 to the thickness of the anode sheet is 0.03-0.05, that is, the thickness of the gap coating area 320 is 3% to 5% of the thickness of the anode sheet. Limiting this ratio allows the user to adjust the thickness of the gap coating area 320 according to the actual thickness of the anode sheet, which can not only ensure that the curling and bending phenomenon of the end of the anode sheet is alleviated, but also avoid the thickness of the gap coating area 320 being too thick and occupying a large space, affecting the volume energy density of the battery cell.

[0059] For example, the ratio of the thickness of the gap coating area 320 to the thickness of the anode sheet can be any value among 0.03, 0.04 and 0.05, so that the gap coating area 320 can reduce the space occupied while preventing the bending of the end of the anode sheet, and is beneficial to ensuring the uniformity of the surface of the end of the anode sheet.

[0060] It should be noted that, along the length direction, the local coating area 130 is located at the end of the second side 120 of the base layer 100. After winding to form a battery cell, the local coating area 130 is located on the side of the base layer 100 away from the cathode sheet. Along the thickness direction, the area of ​​the first active material layer 200 covered by the projection of the local coating area 130 faces the active material on the surface of the cathode sheet.

[0061] refer to Figures 1 to 5 According to the battery cell of the embodiment of the present application, it includes a cathode sheet, a diaphragm and an anode sheet in any of the above embodiments. Along the thickness direction, the diaphragm is located between the cathode sheet and the anode sheet. The diaphragm is used to separate the cathode sheet from the anode sheet to prevent the battery cell from short circuiting.

[0062] Specifically, the size of the anode sheet is larger than that of the cathode sheet, that is, the length of the anode sheet is greater than the length of the cathode sheet, and the width of the anode sheet is greater than the width of the cathode sheet. This ensures that the active material on the surface of the anode sheet corresponds to the active material on the surface of the cathode sheet, which is beneficial to improving lithium precipitation. In addition, the ends of the anode sheet have anti-bending properties along the length direction. After the anode sheet is cut, the gap coating area located within the local coating area can prevent the anode sheet from bending, facilitating the battery cell winding operation, and helping to improve the quality and pass rate of the battery cell.

[0063] The embodiments of the present application have been described in detail above with reference to the accompanying drawings. However, the present application is not limited to the above embodiments. Various modifications can be made within the scope of knowledge possessed by ordinary technicians in the relevant technical field without departing from the purpose of the present application. In addition, the embodiments of the present application and the features of the embodiments can be combined with each other unless there is a conflict.

Claims

1. An anode sheet having a thickness direction, a length direction and a width direction perpendicular to each other, characterized in that: include: A base layer, wherein the base layer includes a first side and a second side opposite to each other along the thickness direction, and at least one end of the second side is provided with a local coating area along the length direction; a first active material layer covering the first side; A second active material layer is provided, wherein an area other than the second side partial coating region is covered with the second active material layer, and a portion of the partial coating region is covered with the second active material layer.

2. The anode sheet according to claim 1, characterized in that: The first active material layer includes a first main coating area and a thinned coating area, the first main coating area is connected to the thinned coating area, along the thickness direction, the thickness of the thinned coating area is less than the thickness of the first main coating area, and the thinned coating area corresponds to the position of the second active material layer covering the local coating area.

3. The anode sheet according to claim 2, characterized in that: The second active material layer includes a gap coating area, the gap coating area is located in the local coating area, and the gap coating area covers a portion of the local coating area, the thickness of the gap coating area is a, the thickness of the thinned coating area is b, and the thickness of the first main coating area is c, wherein a+b=c.

4. The anode sheet according to claim 2, characterized in that: Along the thickness direction, the thickness of the skived coating area is b, and the thickness of the first main coating area is c, wherein the value range of b / c is 0.95 to 0.

97.

5. The anode sheet according to claim 1, characterized in that: The second active material layer includes a second main coating area and a gap coating area, the second main coating area covers the area outside the local coating area on the second side, the gap coating area covers a part of the local coating area, and the thickness of the gap coating area is less than the thickness of the second main coating area.

6. The anode sheet according to claim 5, characterized in that: The intermittent coating area includes at least two coating stripes. Along the length direction, the coating stripes extend from the edge of the base layer to connect with the second main coating area, and along the width direction, the coating stripes are distributed at intervals.

7. The anode sheet according to claim 6, characterized in that: Along the width direction, the width of the coating stripe is d, and then 0mm<d≤5mm.

8. The anode sheet according to claim 5, characterized in that: The thickness of the gap coating area is 3um-6um.

9. The anode sheet according to claim 5, characterized in that: The ratio of the thickness of the gap coating area to the thickness of the anode sheet is 0.03-0.

05.

10. A battery cell, characterized in that: include: cathode sheet; diaphragm; The anode sheet according to any one of claims 1 to 9, wherein the separator is located between the anode sheet and the cathode sheet along the thickness direction.

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