A lithium-ion battery cover plate, battery and its manufacturing method

Abstract

This application relates to a lithium-ion battery cover plate, a battery and a manufacturing method thereof. The lithium-ion battery cover plate of this application includes: a first end plate, a first adhesive layer, a substrate, a second adhesive layer, a second end plate and a conduction body; wherein, the first adhesive layer is arranged on the lower surface of the first end plate; the substrate is arranged on the lower surface of the first adhesive layer; the second adhesive layer is arranged on the lower surface of the substrate; the second end plate is arranged on the lower surface of the second adhesive layer; both the first adhesive layer and the second adhesive layer are annular structures, forming a buffer cavity, and the conduction body is arranged in the buffer cavity. The first end plate and the second end plate of the lithium-ion battery cover plate of this application adopt a double-sided adhesive sealing method, which requires a smaller sealing space than the traditional single-sided adhesive sealing method and has a more reliable sealing performance. Its structure has higher strength and stability than the single-sided adhesive structure.

Description

Technical Field

[0001] This application relates to the technical field of lithium-ion batteries, and more particularly, to a lithium-ion battery cover plate, a battery, and a manufacturing method thereof. Background Art

[0002] Lithium-ion batteries, especially button-type structures, adopt a combination riveting structure of upper and lower half shells similar to primary button / button batteries. Currently, many domestic manufacturers have switched to developing a "cover plate + shell" combined welding structure, which includes traditional riveting structures, laminated adhesive structures, etc. For traditional riveting seal structures, considering structural strength and sealing reliability, a relatively large thickness must be set; in traditional riveting cover plates, the compression ratio of the sealing ring gradually decreases during use due to temperature aging and other reasons, resulting in a decline in sealing effect and reliability; in laminated adhesive structures, the adhesive layer serves as both a sealing adhesive and a structural adhesive. To reduce the thickness of the structure, the adhesive layer is generally set relatively thin, but it is difficult to ensure sufficient adhesive strength.

[0003] In addition, in order to set PTC (current temperature control device), CID (current interruption device), and VENT (pressure relief and explosion-proof device) in traditional large battery riveting cover plates, sufficient height space must be sacrificed. In micro-miniature battery structures, due to space limitations, it is difficult to set one or more of them, making it difficult to fully ensure the safety performance of the battery. Summary of the Invention

[0004] The purpose of this application is to provide a lithium-ion battery cover plate, a battery, and a manufacturing method thereof, so that the sealing performance and structural strength of the manufactured lithium-ion battery cover plate are both improved.

[0005] The embodiments of this application are implemented as follows:

[0006] In a first aspect, this application provides a lithium-ion battery cover plate, including: a first end plate, a first adhesive layer, a substrate, a second adhesive layer, a second end plate, and a conduction body; wherein, the first adhesive layer is disposed on the lower surface of the first end plate; the substrate is disposed on the lower surface of the first adhesive layer; the second adhesive layer is disposed on the lower surface of the substrate; the second end plate is disposed on the lower surface of the second adhesive layer; the first adhesive layer, the substrate, and the second adhesive layer are all annular structures, forming a buffer cavity, and the conduction body is disposed in the buffer cavity.

[0007] In one embodiment, the lithium-ion battery cover plate further includes: a pressure relief and explosion-proof groove, disposed on the upper surface of the second end plate.

[0008] In one embodiment, the pressure relief and explosion-proof groove is an annular structure, and the outer diameter of the pressure relief and explosion-proof groove is greater than the outer diameter of the conduction body, and the inner diameter of the pressure relief and explosion-proof groove is less than the inner diameter of the second adhesive layer.

[0009] In one embodiment, the inner diameters of the first adhesive layer, the substrate, and the second adhesive layer are all equal, and the inner diameter of the second adhesive layer is greater than the outer diameter of the conduction body.

[0010] In one embodiment, the outer diameters of the first adhesive layer and the second adhesive layer are equal, and the outer diameter of the second adhesive layer is smaller than the outer diameter of the substrate.

[0011] In one embodiment, the axes of the first adhesive layer, the substrate, and the second adhesive layer coincide.

[0012] In one embodiment, the first end plate and the second end plate have the same shape and structure.

[0013] In one embodiment, the axes of the first end plate and the second end plate coincide.

[0014] In a second aspect, the present application provides a battery, including a housing, an electrode group, a tab, and the lithium-ion battery cover plate according to any one of the above embodiments; the lithium-ion battery cover plate is disposed on the housing; the electrode group is disposed inside the housing; the tab is disposed on the electrode group.

[0015] In a third aspect, the present application provides a method for manufacturing a battery cover plate, including:

[0016] Dispose the first adhesive layer on the first end plate;

[0017] Cover the substrate on the first adhesive layer, wherein both the substrate and the first adhesive layer are annular structures;

[0018] Perform thermal gluing treatment and cooling treatment on the first end plate, the first adhesive layer, and the substrate to fix the first end plate, the first adhesive layer, and the substrate;

[0019] Dispose the second adhesive layer on the second end plate, and the second adhesive layer is an annular structure;

[0020] Place the conductor into the hollow part between the substrate and the first adhesive layer;

[0021] Cover the second end plate provided with the second adhesive layer on the conductor;

[0022] Perform thermal gluing treatment and cooling treatment on the second end plate, the second adhesive layer, and the substrate to fix the second end plate, the second adhesive layer, and the substrate;

[0023] Weld the two ends of the conductor to the first end plate and the second end plate respectively.

[0024] The beneficial effects of the present application compared with the prior art are as follows: The lithium-ion battery cover plate of the present application adopts a double-sided adhesive sealing method between the first end plate and the second end plate, which has higher space utilization than the traditional single-sided adhesive sealing method; it has a double sealing structure, improving the sealing performance of the cover plate; the double-sided symmetric adhesive structure has higher strength and stability than the single-sided adhesive structure, and the safety performance such as current blocking, pressure relief, and explosion prevention is improved. Description of the Drawings

[0025] To more clearly illustrate the technical solutions of the embodiments of the present application, the following will briefly introduce the drawings required for use in the embodiments. It should be understood that the following drawings only show certain embodiments of the present application, and therefore should not be regarded as a limitation of the scope. For those of ordinary skill in the art, without creative efforts, other relevant drawings can also be obtained based on these drawings.

[0026] Figure 1 Schematic diagram of a battery structure shown in an embodiment of the present application.

[0027] Figure 2 Schematic diagram of the structure of a lithium-ion battery cover plate shown in an embodiment of the present application.

[0028] Figure 3 Schematic flow chart of a manufacturing method of a battery cover plate shown in an embodiment of the present application.

[0029] Icon:

[0030] 1 - Battery; 11 - Lithium-ion battery cover plate; 12 - Housing; 13 - Electrode group; 14 - Tab; 100 - First end plate; 200 - First adhesive layer; 300 - Substrate; 400 - Second adhesive layer; 500 - Second end plate; 510 - Pressure relief and explosion-proof groove; 600 - Conductive body; 700 - Buffer cavity. Specific embodiments

[0031] The terms "first", "second", "third", etc. are only used for distinguishing descriptions, do not represent the serial number of arrangement, and cannot be understood as indicating or implying relative importance.

[0032] In addition, terms such as "horizontal", "vertical", "overhanging", etc. do not mean that the components are required to be absolutely horizontal or overhanging, but can be slightly inclined. For example, "horizontal" only means that its direction is more horizontal relative to "vertical", and does not mean that the structure must be completely horizontal, but can be slightly inclined.

[0033] In the description of the present application, it should be noted that the orientation or positional relationship indicated by terms such as "inner", "outer", "left", "right", "upper", "lower", etc. is based on the orientation or positional relationship shown in the drawings, or the orientation or positional relationship in which the product of this application is usually placed during use. It is only for the convenience of describing the present application and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as a limitation of the present application.

[0034] In the description of the present application, unless otherwise clearly specified and limited, the terms "arranged", "installed", "connected", and "coupled" shall be understood in a broad sense. For example, it may be a fixed connection, a detachable connection, or an integral connection; it may be a mechanical connection or an electrical connection; it may be directly connected or indirectly connected through an intermediate medium, and it may be the communication inside two components.

[0035] The technical solution of the present application will be clearly and completely described below with reference to the accompanying drawings.

[0036] Please refer to Figure 1 , which is a schematic structural diagram of the battery 1 shown in an embodiment of the present application. A battery 1 includes a lithium-ion battery cover plate 11, a housing 12, an electrode group 13, and a tab 14. Among them, the lithium-ion battery cover plate 11 is arranged on the housing 12, and the lithium-ion battery cover plate 11 can be welded to the opening of the housing by laser welding, resistance welding, ultrasonic welding, etc. to form an external support and sealing structure of the battery 1. The electrode group 13 is arranged in the housing 12, and the tab 14 is arranged on the electrode group 13.

[0037] Please refer to Figure 2 , which is a schematic structural diagram of the lithium-ion battery cover plate 11 shown in an embodiment of the present application. A lithium-ion battery cover plate 11 includes: a first end plate 100, a first adhesive layer 200, a substrate 300, a second adhesive layer 400, a second end plate 500, and a conductor 600. The first adhesive layer 200 is arranged on the lower surface of the first end plate 100; the substrate 300 is arranged on the lower surface of the first adhesive layer 200; the second adhesive layer 400 is arranged on the lower surface of the substrate 300; the second end plate 500 is arranged on the lower surface of the second adhesive layer 400; the first adhesive layer 200 and the substrate 300 and the second adhesive layer 400 are all annular structures to form a buffer cavity 700, and the conductor 600 is arranged in the buffer cavity 700.

[0038] In one embodiment, a pressure relief and explosion-proof groove 510 is further arranged on the upper surface of the second end plate 500. The pressure relief and explosion-proof groove 510 is located at the bottom of the buffer cavity 700. The pressure relief and explosion-proof groove 510 is an annular structure, and the outer diameter of the pressure relief and explosion-proof groove 510 is greater than the outer diameter of the conductor 600, and the inner diameter of the pressure relief and explosion-proof groove 510 is smaller than the inner diameter of the second adhesive layer 400.

[0039] Among them, the material of the first end plate 100 can be metals and their alloys such as aluminum, iron, nickel, etc., and the processing method can be stamping, machining, powder metallurgy, etc. In one embodiment, the material of the first end plate 100 is preferably a stainless steel iron-based alloy material with relatively high strength and stiffness, and is formed by stamping and machining to ensure the overall structural strength and stability of the lithium-ion battery cover plate 11. The surface of the first end plate 100 can be treated according to the size, use, and adhesive material of the battery 1 to improve the adhesive bonding performance.

[0040] The material of the first adhesive layer 200 can be non-metallic adhesive materials such as epoxy resin, polypropylene (PP), polyethylene (PE), acrylic acid, etc., and the processing method can be lamination, screen printing, etc. The first adhesive layer 200 is used to connect the first end plate 100 and the substrate 300, providing sufficient connection strength, sealing performance, and insulation. In one embodiment, the material of the first adhesive layer 200 is preferably a single-component polypropylene (PP) semi-solid adhesive film, which is formed by die-cutting.

[0041] The material of the substrate 300 can be metals and their alloys such as aluminum, iron, nickel, etc., and the processing method can be stamping, machining, powder metallurgy, etc. In one embodiment, the material of the substrate 300 is preferably a stainless steel iron-based alloy material with high strength and stiffness, which is formed by stamping and machining to ensure the overall structural strength and stability of the lithium-ion battery cover plate 11. The surface of the substrate 300 can be treated according to the size, use, and adhesive material of the battery 1 to improve the adhesive bonding performance.

[0042] The material of the second adhesive layer 400 can be non-metallic adhesive materials such as epoxy resin, PP, PE, acrylic acid, etc., and the processing method can be lamination, screen printing, etc. The second adhesive layer 400 is used to connect the substrate 300 and the second end plate 500, providing sufficient connection strength, sealing performance, and insulation. In one embodiment, the material of the second adhesive layer 400 is preferably an epoxy resin semi-solid adhesive film, which is formed by die-cutting.

[0043] The material of the second end plate 500 can be metals and their alloys such as aluminum, iron, nickel, etc., and the processing method can be stamping, machining, powder metallurgy, etc. In one embodiment, the material of the second end plate 500 is preferably aluminum or aluminum alloy with moderate strength and stiffness, which is convenient for the manufacturing and pressure relief action of the pressure relief and explosion-proof groove 510 on the second end plate 500. The second end plate 500 is formed by stamping and machining. The surface of the second end plate 500 can be treated according to the size, use, and adhesive material of the battery 1 to improve the adhesive bonding performance.

[0044] The conductor 600 can be made of PTC functional material (Positive Temperature Coefficient, abbreviated as PTC, that is, positive temperature coefficient, generally referring to semiconductor materials or components with a very large positive temperature coefficient). Its material can be metals and their alloys such as aluminum, iron, copper, nickel, etc., or non-PCT functional conductive metal materials such as aluminum, iron, copper, nickel, etc. Its shape can be in the form of a shrapnel structure, and it elastically contacts the first end plate 100 and the second end plate 500 by its own elasticity. The processing method of the conductor 600 can be stamping, machining forming, etc. The main function of the conductor 600 is to electrically connect the first end plate 100 and the second end plate 500, which is the necessary path for the current of the battery 1. When the temperature rises during large current discharge such as short circuit of the battery 1, the conductor 600 can rapidly increase its internal resistance to prevent the battery 1 from continuously discharging with large current. In one embodiment, the material of the conductor 600 is preferably PTC functional material, and it is formed by stamping and machining.

[0045] In one embodiment, the working principle of the battery 1: Under normal charge and discharge conditions of the battery 1, the current sequentially passes through the tab 14, the edge of the lower surface of the second end plate 500, the central part of the second end plate 500, the conductor 600, and the first end plate 100.

[0046] In one embodiment, the electrolyte blocking principle: A buffer cavity 700 that can buffer a small amount of electrolyte is provided between the bonded and sealed areas of the first end plate 100, the substrate 300, and the second end plate 500. The buffer cavity 700 can be a cavity or filled with a foaming material or asbestos material that can adsorb a small amount of electrolyte. When the battery 1 fails after long-term use, a small amount of electrolyte leaks along the bonded and sealed path inside the lithium-ion battery cover 11. The small amount of electrolyte can be buffered in the buffer cavity 700 to prevent further leakage of the electrolyte, making the sealing structure of the lithium-ion battery cover 11 more durable and reliable.

[0047] In one embodiment, the pressure relief, explosion-proof and current blocking principle: When the internal pressure of the battery 1 rises, the pressure pushes the central part of the pressure relief and explosion-proof groove 510 on the second end plate 500 to deform outward. When the internal pressure rises to the strength threshold of the pressure relief and explosion-proof groove 510, the second end plate 500 breaks at the pressure relief and explosion-proof groove 510. At this time, the central part of the pressure relief and explosion-proof groove 510, the conductor 600, and the first end plate 100 as a whole fall off outward, forming an exhaust channel from the inside to the outside of the battery 1. When the battery 1 undergoes a pressure relief and explosion-proof action, the central part of the second end plate 500 breaks and separates at the pressure relief and explosion-proof groove 510, blocking the current channel from the inside to the outside of the battery 1 and preventing dangers such as combustion and explosion during continued charge and discharge when the battery 1 is abnormally used.

[0048] In one embodiment, when the conductor 600 selects a PTC functional material, the working principle of current temperature control is as follows: When the battery 1 undergoes large current charging and discharging beyond the normal operating range, the overall temperature of the battery 1 will rise abnormally. When the temperature of the conductor 600 rises to the threshold value, the resistance of the conductor 600 will increase rapidly, thereby effectively suppressing the continued sharp rise in the temperature of the battery 1, rapidly reducing the loop current of the battery 1, and effectively suppressing the dangers such as combustion and explosion of the battery 1 caused by excessive temperature.

[0049] In one embodiment, the inner diameters of the first adhesive layer 200, the substrate 300, and the second adhesive layer 400 are all equal, and the inner diameter of the second adhesive layer 400 is greater than the outer diameter of the conductor 600. In the lithium-ion battery cover plate 11 of this embodiment, the substrate 300 is used as the main supporting structure, and the first adhesive layer 200 and the second adhesive layer 400 with equal inner diameters are used to adhesively bond the first end plate 100 and the second end plate 500. While ensuring reliable sealing performance, this structure can provide higher structural strength and stability than a single-sided adhesive bonding structure.

[0050] In one embodiment, the outer diameters of the first adhesive layer 200 and the second adhesive layer 400 are equal, and the outer diameter of the second adhesive layer 400 is smaller than the outer diameter of the substrate 300. In the lithium-ion battery cover plate 11 of this embodiment, the first adhesive layer 200 and the second adhesive layer 400 with equal outer diameters are used for double-sided adhesive bonding and sealing of the first end plate 100 and the second end plate 500, which has more reliable sealing performance than the traditional single-sided adhesive bonding and sealing method.

[0051] In one embodiment, the axes of the first adhesive layer 200, the substrate 300, and the second adhesive layer 400 coincide.

[0052] In one embodiment, the shapes and structures of the first end plate 100 and the second end plate 500 are the same, and the axes of the first end plate 100 and the second end plate 500 coincide. Through such a structure, the strength and stability of the overall structure of the lithium-ion battery cover plate 11 can be ensured.

[0053] Please refer to Figure 3 , which is a schematic flow chart of the manufacturing method of the battery cover plate shown in an embodiment of the present application. A manufacturing method of a battery cover plate for manufacturing the lithium-ion battery cover plate 11 as shown in Figure 1 is as follows. The specific steps include:

[0054] Step S210: Dispose the first adhesive layer 200 on the first end plate 100.

[0055] The first end plate 100 made of stainless steel iron-based alloy is stamped and machined to form a circular first end plate 100. The first adhesive layer 200 made of polypropylene adhesive material is uniformly coated on the surface of the first end plate 100, and the middle of the first adhesive layer 200 is made to be an annulus during coating.

[0056] Step S220: Cover the substrate 300 on the first adhesive layer 200, where both the substrate 300 and the first adhesive layer 200 are annular structures.

[0057] Pre-stamp and process the substrate 300 made of stainless steel iron-based alloy into an annular substrate 300 with an annular structure in the middle, and the inner diameter of the substrate 300 is equal to the inner diameter of the first adhesive layer 200. Cover the annular substrate 300 on the first adhesive layer 200, and gently tap it to make the surface of the substrate 300 fully contact with the first adhesive layer 200.

[0058] Step S230: Perform thermal gluing treatment and cooling treatment on the first end plate 100, the first adhesive layer 200, and the substrate 300 to fix the first end plate 100, the first adhesive layer 200, and the substrate 300.

[0059] Under certain temperature and pressure conditions, perform thermal gluing treatment on the first end plate 100, the first adhesive layer 200, and the substrate 300. The temperature, pressure, and thermal gluing treatment time can be determined according to specific process requirements and the material of the first adhesive layer 200. After the thermal gluing treatment is completed, perform cooling to make the first end plate 100, the first adhesive layer 200, and the substrate 300 fully fixed by gluing. The cooling time and temperature are determined according to specific process requirements.

[0060] Step S240: Set the second adhesive layer 400 on the second end plate 500, and the second adhesive layer 400 is an annular structure.

[0061] Adopt the same method as setting the first adhesive layer 200 on the first end plate 100 to evenly coat the second adhesive layer 400 made of epoxy resin material on the surface of the second end plate 500, and make the middle of the second adhesive layer 400 annular when coating. During manufacturing, ensure that the axes of the first adhesive layer 200, the substrate 300, and the second adhesive layer 400 coincide.

[0062] Step S250: Place the conductor 600 into the hollow part between the substrate 300 and the first adhesive layer 200.

[0063] Place the conductor 600 made of ceramic composite material into the buffer cavity 700 formed by the hollow part between the substrate 300 and the first adhesive layer 200.

[0064] Step S260: Cover the second end plate 500 provided with the second adhesive layer 400 on the conductor 600.

[0065] The second end plate 500 made of aluminum alloy is pre-stamped and machined into a circular structure with the same shape and structure as the first end plate 100. The middle parts of the first adhesive layer 200 and the second adhesive layer 400 are both annular structures, which can accommodate the conductor 600. Cover the second end plate 500 provided with the second adhesive layer 400 on the conductor 600, align the axes of the second end plate 500 and the first end plate 100 vertically, and ensure the stability of the overall structure.

[0066] Step S270: Perform heat gluing treatment and cooling treatment on the second end plate 500, the second adhesive layer 400 and the substrate 300 to fix the second end plate 500, the second adhesive layer 400 and the substrate 300.

[0067] Using the same method as in step S230, under certain temperature and pressure conditions, perform heat gluing treatment on the second end plate 500, the second adhesive layer 400 and the substrate 300. The temperature, pressure and heat gluing treatment time can be determined according to specific process requirements and the material of the second adhesive layer 400. After the heat gluing treatment is completed, perform cooling to fully fix and bond the second end plate 500, the second adhesive layer 400 and the substrate 300. The cooling time and temperature are determined according to specific process requirements.

[0068] Perform fine grinding on the overall structure of the cooled lithium-ion battery cover plate 11 so that the inner diameters of the first adhesive layer 200, the substrate 300 and the second adhesive layer 400 are equal. At the same time, process and grind the first adhesive layer 200 and the second adhesive layer 400 so that the outer diameters of the first adhesive layer 200 and the second adhesive layer 400 are equal, and the outer diameter of the second adhesive layer 400 is smaller than the outer diameter of the substrate 300, and the inner diameter of the second adhesive layer 400 is larger than the outer diameter of the conductor 600.

[0069] Step S280: Weld the two ends of the conductor 600 to the first end plate 100 and the second end plate 500 respectively.

[0070] After the heat gluing treatment, the conductor 600 is wrapped inside the first end plate 100 and the second end plate 500. By means of laser welding, resistance welding or ultrasonic welding, one end of the conductor 600 is welded to the surface of the first end plate 100, and the other end of the conductor 600 is welded to the surface of the second end plate 500, so that the conductor 600 is electrically connected to the first end plate 100 and the second end plate 500, thereby forming a necessary path for the current of the battery 1. During welding, it is necessary to ensure that the first end plate 100 and the second end plate 500 are vertically aligned and there is as little misalignment as possible.

[0071] The selection of different thicknesses and materials for each structure in the lithium-ion battery cover plate 11 is related to the overall strength, stiffness, sealing performance, pressure relief and explosion-proof pressure and other characteristics of the lithium-ion battery cover plate 11. In one embodiment, according to the actual manufacturing process requirements of the lithium-ion battery cover plate 11, the thickness ranges of the various structures in the lithium-ion battery cover plate 11 can be as follows:

[0072] The thickness of the first end plate 100 < 0.2 mm;

[0073] The thickness of the first adhesive layer 200 < 0.2 mm;

[0074] The thickness of the substrate 300 < 0.5 mm;

[0075] The thickness of the second adhesive layer 400 < 0.2 mm;

[0076] The thickness of the second end plate 500 < 0.2 mm;

[0077] The thickness of the conductor 600 < 1 mm;

[0078] The overall thickness of the lithium-ion battery cover plate 11 < 1 mm.

[0079] Stack and assemble the various structures in the lithium-ion battery cover plate 11 according to the above steps. The stacking and assembly relationship is related to the hot pressing process and also to the process requirements for manufacturing the lithium-ion battery cover plate 11. A single-piece hot pressing process can be selected, which is convenient for automated production, reduces the hot pressing time, and thus improves the manufacturing efficiency; a multi-piece hot pressing process can also be selected, which increases the hot pressing time, improves the bonding strength and the sealing durability of the lithium-ion battery cover plate 11, and at the same time ensures the manufacturing efficiency.

[0080] The lithium-ion battery cover plate 11 manufactured by the above method, when combined with the housing 12 to form the battery 1, can provide functions such as current temperature control, current interruption, and pressure relief and explosion prevention, making the battery 1 have higher safety performance during use.

[0081] It should be noted that, without conflict, the features in the embodiments of the present application can be combined with each other.

[0082] The above are only the preferred embodiments of the present application and are not used to limit the present application. For those skilled in the art, the present application can have various changes and modifications. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present application shall be included in the protection scope of the present application.

Claims

1. A lithium-ion battery cover plate, characterized in that, Comprising: A first end plate; A first adhesive layer disposed on the lower surface of the first end plate; A substrate disposed on the lower surface of the first adhesive layer; A second adhesive layer disposed on the lower surface of the substrate, the inner diameters of the first adhesive layer, the substrate, and the second adhesive layer being equal; A second end plate disposed on the lower surface of the second adhesive layer; And A conductor, the first adhesive layer, the substrate, and the second adhesive layer are all annular structures, forming a buffer cavity, and the conductor is disposed in the buffer cavity; wherein, the inner diameter of the second adhesive layer is greater than the outer diameter of the conductor; A pressure relief and explosion-proof groove disposed on the upper surface of the second end plate, the pressure relief and explosion-proof groove being an annular structure, and the outer diameter of the pressure relief and explosion-proof groove being greater than the outer diameter of the conductor, and the inner diameter of the pressure relief and explosion-proof groove being less than the inner diameter of the second adhesive layer.

2. The lithium-ion battery cover plate according to claim 1, characterized in that, The outer diameters of the first adhesive layer and the second adhesive layer are equal, and the outer diameter of the second adhesive layer is less than the outer diameter of the substrate.

3. The lithium-ion battery cover plate according to claim 1, wherein The axes of the first adhesive layer, the substrate, and the second adhesive layer coincide.

4. The lithium-ion battery cover plate according to claim 1, characterized in that, The shapes and structures of the first end plate and the second end plate are the same.

5. The lithium-ion battery cover plate according to claim 4, characterized in that, The axes of the first end plate and the second end plate coincide.

6. A battery, characterized in that, Comprising a housing, an electrode group, a tab, and the lithium-ion battery cover plate according to any one of claims 1 to 5; The lithium-ion battery cover plate is disposed on the housing; The electrode group is disposed in the housing; The tab is disposed on the electrode group.

7. A manufacturing method of a battery cover plate, characterized in that, The manufacturing method of the battery cover plate is used to manufacture the lithium-ion battery cover plate according to any one of claims 1 to 5; the method includes: Disposing a first adhesive layer on a first end plate; Covering the substrate on the first adhesive layer, wherein the substrate and the first adhesive layer are both annular structures; Performing heat gluing treatment and cooling treatment on the first end plate, the first adhesive layer, and the substrate to fix the first end plate, the first adhesive layer, and the substrate; Disposing a second adhesive layer on a second end plate, the second adhesive layer being an annular structure, the inner diameters of the first adhesive layer, the substrate, and the second adhesive layer being equal, and the inner diameter of the second adhesive layer being greater than the outer diameter of the conductor; Placing the conductor into the hollow part of the substrate and the first adhesive layer; Covering the second end plate provided with the second adhesive layer on the conductor; Performing heat gluing treatment and cooling treatment on the second end plate, the second adhesive layer, and the substrate to fix the second end plate, the second adhesive layer, and the substrate; Welding the two ends of the conductor to the first end plate and the second end plate respectively; Providing a pressure relief and explosion-proof groove on the upper surface of the second end plate, the pressure relief and explosion-proof groove being an annular structure, and the outer diameter of the pressure relief and explosion-proof groove being greater than the outer diameter of the conductor, and the inner diameter of the pressure relief and explosion-proof groove being less than the inner diameter of the second adhesive layer.

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