Battery cell and battery

Abstract

The utility model discloses a kind of electric core and battery.The electric core includes: positive sheet, negative sheet and diaphragm, positive sheet, diaphragm and negative sheet are sequentially laminated and wound into winding structure;Positive sheet includes: current collector, including oppositely arranged inner surface and outer surface, outer surface includes coating area and blank area, the end of blank area away from coating area is the winding terminal point of positive sheet, blank area is the outer surface of winding structure, coating area is connected with blank area, blank area includes first part and second part, first part is between coating area and second part;Active material layer is set to inner surface and coating area;Fixed layer is set to first part, and fixed layer includes multiple protrusions, and the protrusion is used for abutting against shell;Back glue is set to second part, and back glue is used for bonding shell.The electric core of the utility model can effectively improve the fixing effect with shell.

Description

Technical Field

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

[0002] In the current lithium-ion manufacturing field, securing the bare cell is a crucial step in ensuring mechanical reliability. Currently, securing the bare cell primarily relies on hot melt adhesive on the non-installation side after winding. However, this method only secures one side of the bare cell, making it difficult to meet the need for securing the cell in multiple directions (length, width, and height). During drop tests, due to poor adhesion between the bare cell and the casing, and the presence of a small amount of free electrolyte inside the cell, the cell is prone to shifting along its length and width due to the lubricating effect of the free electrolyte, potentially causing the electrode to scrape against the casing and short-circuit. Utility Model Content

[0003] The present invention aims to solve at least one of the technical problems existing in the prior art. To this end, the present invention proposes a battery cell that can effectively improve the fixation effect with the casing.

[0004] This utility model also proposes a battery.

[0005] According to an embodiment of the first aspect of the present invention, a battery cell includes: a positive electrode sheet, a negative electrode sheet, and a separator, wherein the positive electrode sheet, the separator, and the negative electrode sheet are sequentially stacked and wound into a wound structure;

[0006] The positive electrode includes:

[0007] The current collector includes an inner surface and an outer surface disposed opposite to each other. The outer surface includes a coated area and a blank area. The end of the blank area away from the coated area is the winding end point of the positive electrode sheet. The blank area is the outer surface of the winding structure. The coated area is connected to the blank area. The blank area includes a first part and a second part. The first part is located between the coated area and the second part.

[0008] An active material layer is disposed on the inner surface and the coating area;

[0009] A fixing layer is disposed in the first part, the fixing layer including a plurality of protrusions for abutting against the housing;

[0010] An adhesive backing is provided on the second part, the adhesive backing being used to bond the housing.

[0011] The battery cell according to the first aspect of the present invention has at least the following beneficial effects: it can effectively improve the fixing effect with the housing.

[0012] In this application, a fixing layer and an adhesive layer are provided in the blank area of ​​the current collector. The fixing layer is located in the first part of the blank area, and the adhesive layer is located in the second part of the blank area. The fixing layer includes multiple spaced protrusions, which form a rough surface on the unadhesive surface of the battery cell (the first part), increasing the frictional resistance between the battery cell and the casing. Compared with battery cells of related technologies that only have an adhesive layer and no fixing layer, the battery cell of this application, due to its fixing layer with multiple protrusions, can increase the frictional resistance between the battery cell and the casing, effectively suppressing the movement of the battery cell in the long and wide planar directions and improving the fixing effect of the battery cell.

[0013] According to some embodiments of the present invention, the thickness of the protrusion is D1, and the thickness of the active material layer is D2, where D1 ≤ D2.

[0014] According to some embodiments of this utility model, the area of ​​the protrusion is S1, 5mm. 2 ≤S1≤30mm 2 .

[0015] According to some embodiments of the present invention, along the thickness direction of the battery cell, the projected area of ​​the battery cell is S, and the sum of the areas of all the protrusions is S2, where 0.1*S≤S2≤0.5*S.

[0016] According to some embodiments of this utility model, along the thickness direction of the battery cell, the projected area of ​​the battery cell is S, and the area of ​​the fixing layer is S3, where 0.1*S≤S3≤0.9*S.

[0017] According to some embodiments of the present invention, the shape of the protrusion is one of a circle, a rhombus, a square, or a polygon.

[0018] According to some embodiments of this utility model, the protrusion is made of one of silicon oxide ceramic, alumina ceramic, or boehmite ceramic.

[0019] The battery according to a second aspect of the present invention includes the battery cell described in any of the above claims;

[0020] A housing having a cavity in which the battery cell is housed.

[0021] The battery according to the second aspect of the present invention has at least the following beneficial effects: it can effectively improve the fixing effect between the cell and the casing.

[0022] Specifically, the battery cell of this application has a fixing layer and an adhesive layer disposed in the blank area of ​​the current collector. The fixing layer is disposed in the first part of the blank area, and the adhesive layer is disposed in the second part of the blank area. The fixing layer includes multiple spaced protrusions, which form a rough surface on the unadhesive surface (first part) of the battery cell, increasing the frictional resistance between the battery cell and the casing. Compared with battery cells of related technologies that only have an adhesive layer and no fixing layer, the battery cell of this application, due to its fixing layer with multiple protrusions, can increase the frictional resistance between the battery cell and the casing, effectively suppressing the movement of the battery cell in the long and wide planes, and improving the fixing effect of the battery cell. Therefore, batteries with the battery cell of this application can also improve the fixing effect between the battery cell and the casing.

[0023] According to some embodiments of the present invention, the chamber has a first surface near the fixing layer of the battery cell, the first surface being provided with a plurality of grooves, each of the protrusions being accommodated in one of the grooves.

[0024] According to some embodiments of the present invention, the total number of grooves is greater than the total number of protrusions.

[0025] Additional aspects and advantages of this invention will be set forth in part in the description which follows, and in part will be obvious from the description, or may be learned by practice of the invention. Attached Figure Description

[0026] The present invention will be further described below with reference to the accompanying drawings and embodiments, wherein:

[0027] Figure 1 This is a schematic diagram of the outer surface of the positive electrode sheet of this utility model;

[0028] Figure 2 This is a schematic diagram of the inner surface of the positive electrode sheet of this utility model;

[0029] Figure 3 This is a schematic diagram of the blank area of ​​this utility model;

[0030] Figure 4 This is a schematic diagram of the first embodiment of the battery of this utility model;

[0031] Figure 5 This is a schematic diagram of a second embodiment of the battery of this utility model;

[0032] Figure 6 for Figure 5 Enlarged view of point A in the middle;

[0033] Figure 7 This is a schematic diagram of the third embodiment of the battery of this utility model;

[0034] Figure 8 for Figure 7 Enlarged view of point B in the middle.

[0035] Figure label:

[0036] Current collector 100; inner surface 101; outer surface 102; coating area 110; blank area 120; first part 121; second part 122; active material layer 200; fixing layer 300; protrusion 301; backing adhesive 400; battery cell 10; shell 20; groove 201; heat sealing layer 210; metal layer 220; nylon layer 230. Detailed Implementation

[0037] The embodiments of this utility model are described in detail below. Examples of these embodiments are shown in the accompanying drawings, wherein the same or similar reference numerals denote the same or similar elements or elements having the same or similar functions throughout. The embodiments described below with reference to the accompanying drawings are exemplary and are only used to explain this utility model, and should not be construed as limiting this utility model.

[0038] In the description of this utility model, it should be understood that the directional descriptions, such as up, down, front, back, left, right, etc., indicate the directional or positional relationship based on the directional or positional relationship shown in the accompanying drawings. They are only for the convenience of describing this utility model and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limitations on this utility model.

[0039] In the description of this utility model, "several" means one or more, "multiple" means two or more, "greater than," "less than," and "exceeding" are understood to exclude the stated number, while "above," "below," and "within" are understood to include the stated number. The use of "first" and "second" in the description is merely for distinguishing technical features and should not be construed as indicating or implying relative importance, or implicitly indicating the number of indicated technical features, or implicitly indicating the order of the indicated technical features.

[0040] In the description of this utility model, unless otherwise explicitly defined, terms such as "setting," "installation," and "connection" should be interpreted broadly, and those skilled in the art can reasonably determine the specific meaning of the above terms in this utility model in conjunction with the specific content of the technical solution.

[0041] In the description of this utility model, the terms "one embodiment," "some embodiments," "illustrative embodiment," "example," "specific example," or "some examples," etc., refer to specific features, structures, materials, or characteristics described in connection with that embodiment or example, which are included in at least one embodiment or example of this utility model. In this specification, the illustrative expressions of the above terms do not necessarily refer to the same embodiment or example. Furthermore, the specific features, structures, materials, or characteristics described may be combined in any suitable manner in one or more embodiments or examples.

[0042] In the manufacturing process of lithium-ion batteries, the technology for fixing bare cells directly affects the structural stability and safety performance of the battery pack. Currently, the industry commonly uses hot melt adhesive to fix the cells to non-installation surfaces (such as the projection surface along the cell thickness direction) after winding. However, this process suffers from significant deficiencies in three-dimensional constraint. Hot melt adhesive is a material that melts at high temperatures, solidifies upon cooling, and achieves bonding. It has advantages such as low cost and simple processing, and is therefore widely used in lithium-ion battery manufacturing. However, because hot melt adhesive can only achieve localized bonding in a single direction, the cell's degrees of freedom in the length and width directions are not effectively restricted, making it prone to planar displacement under mechanical stress.

[0043] Specifically, the limitations of existing processes are reflected in the following two aspects. First, single-sided bonding cannot form a three-dimensional encapsulation structure. When the battery is subjected to external impacts such as drops or vibrations, the unbonded areas between the cell and the casing will form a displacement buffer zone. Second, the trace amounts of free electrolyte remaining inside the cell will generate a lubricating effect under dynamic operating conditions, further weakening the friction between the interfaces. This combined effect may cause the cell to slide laterally inside the casing. This can lead to relative misalignment between the electrodes and the separator, affecting electrochemical performance, or even cause the tabs to scratch the casing, leading to insulation failure, and even triggering a short circuit inside the cell.

[0044] Based on the above problems, this application proposes a battery cell 10 that can at least partially solve the above problems.

[0045] Reference Figures 1 to 8According to an embodiment of the first aspect of the present invention, the battery cell 10 includes: a positive electrode sheet, a negative electrode sheet, and a separator, wherein the positive electrode sheet, the separator, and the negative electrode sheet are sequentially stacked and wound into a wound structure. The positive electrode sheet includes a current collector 100, an active material layer 200, a fixing layer 300, and an adhesive backing 400. The current collector 100 includes an inner surface 101 and an outer surface 102 disposed opposite to each other. The outer surface 102 includes a coated area 110 and a blank area 120. The end of the blank area 120 away from the coated area 110 is the winding end point of the positive electrode sheet. The blank area 120 is the outer surface 102 of the wound structure. The coated area 110 and the blank area 120 are connected. The blank area 120 includes a first part 121 and a second part 122, wherein the first part 121 is located between the coated area 110 and the second part 122. An active material layer 200 is disposed on the inner surface 101 and the coating area 110. A fixing layer 300 is disposed on the first portion 121, and the fixing layer 300 includes a plurality of protrusions 301 for abutting against the housing 20. An adhesive backing 400 is disposed on the second portion 122 and is used to bond the housing 20.

[0046] The battery according to the first aspect of the present invention has at least the following beneficial effects: it can effectively improve the fixation effect with the housing 20.

[0047] Reference Figures 1 to 3 In this application, a fixing layer 300 and an adhesive backing 400 are provided in the blank area 120 of the current collector 100. The fixing layer 300 is provided in the first part 121 of the blank area 120, and the adhesive backing 400 is provided in the second part 122 of the blank area 120. The fixing layer 300 includes a plurality of spaced protrusions 301, which form a rough surface on the unadhesive surface (first part 121) of the battery cell 10, increasing the frictional resistance between the battery cell 10 and the housing 20. Compared with the battery cell 10 of the related art that only has an adhesive layer without a fixing layer 300, the battery cell 10 of this application, due to having a fixing layer 300 including a plurality of protrusions 301, can increase the frictional resistance between the battery cell 10 and the housing 20, effectively suppress the movement of the battery cell 10 in the long and wide plane directions, and improve the fixing effect of the battery cell 10.

[0048] Specifically, in this application, the non-adhesive surface of the battery cell 10 is provided with a protrusion 301 structure. This protrusion 301 increases the friction between the battery cell 10 and the housing 20, thereby improving the fixing effect of the battery cell 10 without adding an additional limiting structure. This application adopts a method of providing an adhesive backing 400 on one side of the battery cell 10 and a fixing layer 300 with multiple spaced protrusions 301 on the other side. This forms a rough area formed by multiple protrusions 301 on the non-adhesive surface of the battery cell 10, increasing the friction between it and the housing 20, thereby improving the fixing effect between the battery cell 10 and the housing 20. This avoids problems such as the battery cell 10 scraping against the housing 20 due to the adhesive backing 400 falling off, which could lead to risks such as internal short circuits in the battery cell 10. In addition, the fixing layer 300 formed by the protrusions 301 can effectively prevent direct contact between the battery cell 10 and the housing 20. When the battery cell 10 is subjected to a strong impact and is displaced, these three-dimensional protrusions 301 can play a buffering role, avoiding direct contact between the battery cell 10 and the housing 20 and causing safety problems such as internal short circuits of the battery cell.

[0049] According to some embodiments of this utility model, the thickness of the protrusion 301 is D1, and the thickness of the active material layer 200 is D2, where D1 ≤ D2. By limiting the thickness D1 of the protrusion 301 to be no greater than the thickness D2 of the active material layer 200, a smooth transition between the protrusion 301 and the active material layer 200 is ensured, avoiding stress concentration and interface delamination risks caused by height differences. Simultaneously, the overall rigidity of the cell 10 is maintained, ensuring effective frictional resistance when the fixing layer 300 contacts the housing 20 without damaging the active material. Furthermore, this thickness control keeps the top of the protrusion 301 within a safe height range, serving as a physical barrier against preferential wear to prevent the active layer from directly scratching the housing 20. It also allows for direct molding using existing production processes, avoiding additional steps. For example, the protrusion 301 can be bonded to the current collector 100 using an adhesive.

[0050] According to some embodiments of this utility model, the area of ​​protrusion 301 is S1, 5mm. 2 ≤S1≤30mm 2 In this application, multiple protrusions 301 are provided, arranged alternately, for example, in a matrix. The area of ​​each protrusion 301 should not be too large or too small. Since the friction effect is mainly located at the edges of each protrusion 301 when it contacts the housing 20, with the same area of ​​the fixing layer 300, the longer the perimeter of each protrusion 301, the stronger the friction effect, and thus the longer the fixing effect. At the same time, the area of ​​each protrusion 301 should not be designed to be too small. If the area of ​​a single protrusion 301 is too small, the adhesion of the protrusion 301 to the current collector 100 will be reduced, and the manufacturing difficulty will also increase. Therefore, the area of ​​each protrusion 301 is set at 5 mm. 2 Up to 30mm 2Between, for example, 5mm 2 8mm 2 10mm 2 12mm 2 15mm 2 20mm 2 25mm 2 30mm 2 These features enable the protrusion 301 to be easily fixed and manufactured without reducing the friction effect.

[0051] According to some embodiments of this utility model, along the thickness direction of the battery cell 10, the projected area of ​​the battery cell 10 is S, and the sum of the areas of all protrusions 301 is S2, where 0.1*S≤S2≤0.5*S. Since the protrusions 301 inside the battery cell 10 have no effect on the energy density of the battery cell 10, if the number of protrusions 301 is too large or the overall area of ​​the protrusions 301 is too large, it will occupy too much internal space, thereby affecting the energy density of the battery cell 10. Therefore, the sum of the areas of all protrusions 301 needs to be controlled to be less than half of the projected area of ​​the battery cell 10 along the thickness direction, for example, S2=0.5*S, S2=0.4*S, S2=0.3*S, S2=0.2*S, S2=0.1*S, etc. This avoids the energy density loss caused by the excessively large area of ​​the protrusions 301, and also allows the protrusions 301 to maintain a certain frictional force with the shell 20, thereby improving the fixing effect between the battery cell 10 and the shell 20.

[0052] According to some embodiments of this utility model, along the thickness direction of the battery cell 10, the projected area of ​​the battery cell 10 is S, and the area of ​​the fixing layer 300 is S3, where 0.1*S≤S3≤0.9*S. Generally, the side of the battery cell 10 has a corner (curved surface) area, that is, the projection of the battery cell 10 in the thickness direction has a non-planar area at the side corner. The protrusion 301 set in this area cannot contact the surface of the housing 20 in the thickness direction, wasting the internal space of the battery cell 10 and not generating friction with the housing 20. Therefore, the protrusion 301 should be set away from the corner area. In addition, the strength of the top and bottom areas of the first part 121 is low, and it is not suitable to set it as a stress point. Therefore, the protrusion 301 should also be set away from the top and bottom areas of the first part 121. Thus, in this application, as Figure 3As shown, the relationship between the area S3 of the fixed layer 300 and the projected area S (area of ​​the first part 121) in the thickness direction of the cell 10 satisfies 0.1*S≤S3≤0.9*S. For example, it can be S3=0.9*S, S3=0.8*S or S3=0.7*S, etc. This avoids the loss of setting ineffective protrusions 301 in the non-planar area of ​​the side corner, and avoids structurally fragile areas such as the top / bottom. This ensures that each protrusion 301 acts on an effective contact surface with high mechanical benefits. Under the premise of ensuring sufficient friction between the protrusion 301 and the shell 20, the energy density of the cell 10 is improved.

[0053] According to some embodiments of this utility model, the shape of the protrusion 301 is one of the following: circular, rhomboid, square, or polygonal. Specifically, setting the shape of the protrusion 301 to circular increases the frictional force between it and the housing 20, improving the fixing effect of the battery cell 10. Simultaneously, its uniform stress distribution characteristics avoid stress concentration at sharp corners, making it suitable for expansion and contraction with high cycle counts. Setting the shape of the protrusion 301 to a rhomboid or polygonal structure enhances the frictional effect within the same projected area of ​​the protrusion 301 by increasing the effective contact length of the edges, thereby improving the fixing effect. Furthermore, the guide grooves formed by its ridges can guide the flow of electrolyte, improving interfacial wettability. Setting the shape of the protrusion 301 to square, due to its right-angled edges, can more effectively suppress the displacement of the battery cell 10 in the planar direction. In practical use, the shape of the protrusion 301 can be flexibly selected according to parameters such as the size of the battery cell 10 and the material of the housing 20, achieving an optimal match between frictional performance and structural strength while ensuring processing accuracy.

[0054] According to some embodiments of this utility model, the protrusion 301 is made of one of silica ceramic, alumina ceramic, or boehmite ceramic. Specifically, ceramic materials have high hardness and low coefficient of thermal expansion, maintaining stability even under severe mechanical impact and temperature changes. Boehmite ceramic materials can avoid interfacial side reactions caused by the introduction of heterogeneous materials, and can also achieve self-regulating contact pressure through the micro-expansion characteristics during lithium ion insertion / extraction, dynamically maintaining optimal frictional state during charging and discharging.

[0055] Reference Figures 4 to 6 The battery according to a second aspect of the present invention includes a cell 10 as described above, and a housing 20. The housing 20 has a chamber in which the cell 10 is housed.

[0056] The battery according to the second aspect of the present invention has at least the following beneficial effects: it can effectively improve the fixing effect between the cell 10 and the casing 20.

[0057] Reference Figure 4Specifically, the battery cell 10 of this application provides a fixing layer 300 and an adhesive layer in the blank area 120 of the current collector 100. The fixing layer 300 is disposed in the first part 121 of the blank area 120, and the adhesive layer is disposed in the second part 122 of the blank area 120. The fixing layer 300 includes a plurality of spaced protrusions 301, which form a rough surface on the unadhesive surface (first part 121) of the battery cell 10, increasing the frictional resistance between the battery cell 10 and the casing 20. Compared with the battery cell 10 of the related art that only has an adhesive layer and no fixing layer 300, the battery cell 10 of this application, due to the fixing layer 300 including a plurality of protrusions 301, can increase the frictional resistance between the battery cell 10 and the casing 20, effectively suppressing the movement of the battery cell 10 in the long and wide plane directions, and improving the fixing effect of the battery cell 10. Therefore, the battery with the battery cell 10 of this application can also improve the fixing effect between the battery cell 10 and the casing 20.

[0058] According to some embodiments of the present invention, the chamber has a first surface near the fixing layer 300 of the battery cell 10, and the first surface is provided with a plurality of grooves 201, each protrusion 301 being accommodated in a groove 201.

[0059] In related technologies, there are some technical means to fix the battery cell 10 by setting an additional limiting structure or fixing structure inside the housing 20. Although such a structure can constrain the battery cell 10 in multiple directions, such a structure is often complicated in process and will increase the size of the battery cell 10, resulting in a decrease in the energy density of the battery cell 10.

[0060] Based on this, refer to Figure 5 , Figure 6In this application, multiple grooves 201 are provided on the first surface of the fixing layer 300 near the cell 10 in the cavity to match multiple protrusions 301. When the cell 10 is installed in the cavity of the housing 20, the protrusions 301 are accommodated within the grooves 201. Thus, the grooves 201 provide directional limiting space for the protrusions 301 and form multi-directional constraints through the sidewall contact surfaces of the grooves 201, further improving the fixing effect between the cell 10 and the housing 20. At the same time, a gap can be reserved between the inner wall of the grooves 201 and the protrusions 301. This gap can form an adaptive buffer layer. When the cell 10 is subjected to severe impact, there is a certain sliding gap between the protrusions 301 and the grooves 201, avoiding a rigid connection between the protrusions 301 and the grooves 201, and preventing excessive local stress from tearing the electrode sheets when the cell 10 is subjected to impact. While ensuring the high energy density of the battery, mechanical fixing and flexible adaptation between the cell 10 and the housing 20 are achieved. Furthermore, the meshing structure between the groove 201 and the protrusion 301 can guide the deformation direction of the cell 10 during volume expansion, transforming disordered displacement into directional release along the axial direction of the groove 201, thus avoiding stress concentration that could damage the cell 10. Simultaneously, because the groove 201 is provided on the inner surface of the housing 20, corresponding protrusions are formed on the outer surface of the housing 20. These protrusions create a rough surface on the outer surface of the housing 20. Using adhesive tape on this rough surface to bond the battery to the device (such as a mobile phone or other electronic device) helps increase the adhesion between the battery and the device, improving the battery's fixation and preventing it from falling off.

[0061] In addition to the aforementioned method of forming protrusions on the outer surface of the casing 20 to increase the fixing strength between the battery and the device, there are some scenarios where a flat outer surface of the battery is required. Therefore, referring to... Figure 7 , Figure 8 The housing 20 includes a heat-sealing layer 210, a metal layer 220, and a nylon layer 230 from the inside to the outside (i.e., from the direction closest to the battery cell to the direction furthest from the battery cell). The groove 201 is provided in the heat-sealing layer 210. This ensures that the inner surface of the housing 20 is provided with a groove 201 that matches the protrusion 301, increasing the fixing strength between the battery cell 10 and the housing 20. It also ensures that the outer surface of the housing 20 is smooth and flat, meeting different design requirements.

[0062] According to some embodiments of this utility model, the total number of grooves 201 is greater than the total number of protrusions 301. Furthermore, the total number of grooves 201 on the housing 20 is set to be greater than the total number of protrusions 301 on the cell 10. When installing the cell 10 onto the housing 20, this increases the tolerance for errors in cell 10 installation, ensuring that even with minor adjustments to the cell 10's position, the protrusions 301 can still accurately fall into the grooves 201, guaranteeing a tight fit between the cell 10 and the housing 20, further enhancing the overall stability and safety of the battery. This optimized configuration of grooves 201 and protrusions 301 not only simplifies the manufacturing process and reduces manufacturing costs but also improves the ease of installation of the cell 10. Through this design, the cell 10 maintains excellent fixation during long-term use, extending battery life and improving battery safety performance.

[0063] The embodiments of the present invention have been described in detail above with reference to the accompanying drawings. However, the present invention is not limited to the above embodiments. Within the scope of knowledge possessed by those skilled in the art, various changes can be made without departing from the spirit of the present invention. Furthermore, the embodiments of the present invention and the features thereof can be combined with each other unless otherwise specified.

Claims

1. A battery cell, characterized in that, include: A positive electrode, a negative electrode, and a separator, wherein the positive electrode, the separator, and the negative electrode are sequentially stacked and wound into a wound structure; The positive electrode includes: The current collector includes an inner surface and an outer surface disposed opposite to each other. The outer surface includes a coated area and a blank area. The end of the blank area away from the coated area is the winding end point of the positive electrode sheet. The blank area is the outer surface of the winding structure. The coated area is connected to the blank area. The blank area includes a first part and a second part. The first part is located between the coated area and the second part. An active material layer is disposed on the inner surface and the coating area; A fixing layer is disposed in the first part, the fixing layer including a plurality of protrusions for abutting against the housing; An adhesive backing is provided on the second part, the adhesive backing being used to bond the housing.

2. The battery cell according to claim 1, characterized in that, The thickness of the protrusion is D1, and the thickness of the active material layer is D2, where D1 ≤ D2.

3. The battery cell according to claim 1, characterized in that, The area of ​​the protrusion is S1, 5mm. 2 ≤S1≤30mm 2 .

4. The battery cell according to claim 1, characterized in that, Along the thickness direction of the battery cell, the projected area of ​​the battery cell is S, and the sum of the areas of all the protrusions is S2, where 0.1*S≤S2≤0.5*S.

5. The battery cell according to claim 1, characterized in that, Along the thickness direction of the battery cell, the projected area of ​​the battery cell is S, and the area of ​​the fixing layer is S3, where 0.1*S≤S3≤0.9*S.

6. The battery cell according to claim 1, characterized in that, The protrusion can be circular, rhomboid, square, or polygonal in shape.

7. The battery cell according to claim 1, characterized in that, The protrusion is made of one of the following materials: silicon dioxide ceramic, alumina ceramic, or boehmite ceramic.

8. A battery, characterized in that, include: The battery cell according to any one of claims 1 to 7: A housing having a cavity in which the battery cell is housed.

9. The battery according to claim 8, characterized in that, The chamber has a first surface near the fixing layer of the battery cell, and the first surface is provided with a plurality of grooves, each of the protrusions being accommodated in one of the grooves.

10. The battery according to claim 9, characterized in that, The total number of grooves is greater than the total number of protrusions.

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