Battery cover plate

Abstract

The utility model belongs to the technical field of batteries, and provides a battery cover plate which comprises a top cover sheet, a pole and a ceramic piece, the ceramic piece is arranged in the external space, extends into a through hole, is arranged between the pole and the top cover sheet and is fixedly connected with the pole and the top cover sheet, and the ceramic piece is arranged in the external space and extends into the through hole. The pole is fixed in the through hole and is insulated from the top cover plate; the ceramic part is used for replacing an existing upper plastic part, so that the insulating property and the mechanical property are considered at the same time, and the problem that a sealing ring is loosened due to uneven stress or mechanical fatigue of a traditional upper plastic part is effectively solved.

Description

Technical Field

[0001] The utility model belongs to the technical field of batteries and relates to a battery cover. Background Art

[0002] In modern electric vehicle technology, the power battery is a core component, and its performance directly impacts the vehicle's overall performance. The battery cover, part of the battery casing, is typically located at the top of the battery. It connects the positive and negative electrodes of the internal cells to external connections and seals the cells and electrolyte inside, ensuring a tight seal and safety. Therefore, the cover's structural design and material selection are directly related to the battery's reliability and service life.

[0003] A battery cover typically consists of a top cover, a terminal, a sealing ring, an upper plastic, and a lower plastic. Typically, the upper plastic is located on the outside of the top cover, away from the battery cells, while the lower plastic is located on the inside of the top cover, closer to the battery cells. Together, they provide isolation and insulation between the terminal and the top cover, preventing short circuits. Furthermore, due to its location, the upper plastic also bears a stress-bearing role, such as bearing pressure and preventing twisting, to protect the battery's internal structure from external forces.

[0004] Therefore, existing plastic materials (such as PPS plastic particles) need to improve mechanical strength and toughness by adding reinforcing fibers, but in practical applications, there are still some problems:

[0005] 1) Uneven stress: During battery assembly and use, the upper plastic component may be subjected to uneven mechanical stress. For example, during assembly, the fit between the terminal and the upper plastic may cause localized stress concentration, leading to material deformation. This uneven stress can cause localized damage to the upper plastic, compromising its insulation performance and mechanical strength.

[0006] 2) Mechanical fatigue: Even with the addition of reinforcing fibers, PPS plastic can still suffer fatigue damage under repeated mechanical loads. This fatigue damage gradually accumulates, ultimately leading to a decrease in sealing performance. This fatigue damage is particularly pronounced in harsh environments such as high temperature and high humidity.

[0007] 3) Loose seal ring: Due to uneven stress on the upper plastic, mechanical fatigue, or even deformation or damage, the seal ring may lose its original tight fit, causing electrolyte leakage. This not only affects battery performance but also poses a safety hazard.

[0008] In summary, a new solution is still needed to improve the insulation performance and stress conditions of the upper plastic, prevent the loosening of the sealing ring and electrolyte leakage, so as to effectively improve the safety, stability, reliability and service life of the battery and promote the further development of battery applications. Utility Model Content

[0009] In view of the problems existing in the prior art, the purpose of the present invention is to provide a battery cover that uses ceramic parts instead of the existing upper plastic parts to take into account both insulation performance and mechanical properties, and effectively solve the problems of traditional upper plastic parts such as loose sealing rings due to uneven force or mechanical fatigue.

[0010] To achieve this purpose, the present invention adopts the following technical solutions:

[0011] In a first aspect, the present invention provides a battery cover, comprising: a top cover and a pole; the side of the top cover away from the battery cell is an external space, and the side close to the battery cell is an internal space; the top cover is provided with a through hole; the pole is provided in the through hole, and its two ends protrude toward the external space and the internal space respectively;

[0012] The battery cover plate further includes a ceramic component, which is arranged in the external space and extends into the through hole, and is arranged between the pole and the top cover sheet, and is fixedly connected to the pole and the top cover sheet, so that the pole is fixed in the through hole and insulated from the top cover sheet.

[0013] The present invention uses ceramic parts to replace the existing upper plastic parts, that is, the side (outside) of the top cover away from the battery cell is not provided with other plastic parts except the ceramic parts. By providing the ceramic parts, the insulation performance and stress conditions of traditional plastics can be improved, and the mechanical strength, insulation performance and sealing performance of the battery cover can be effectively improved. It can effectively solve the problems of traditional plastic parts such as loose sealing rings due to uneven stress or mechanical fatigue, and can extend battery life and reduce safety risks. The manufacturing and use costs of ceramic parts are low, the process is simple, and production costs can be reduced. Since ceramic parts replace plastic parts, the thickness (protruding height) of the ceramic parts can be significantly reduced while obtaining the same structural strength, which is conducive to improving the height space utilization of the entire battery pack, so that the energy is increased by 1% to 2%.

[0014] The following are preferred technical solutions of the present invention, but are not intended to limit the technical solutions provided by the present invention. Through the following technical solutions, the technical objectives and beneficial effects of the present invention can be better achieved and realized.

[0015] As a preferred technical solution of the present invention, the end surface of the pole at one end of the external space is the top surface, and the end surface of the pole at one end of the internal space is the bottom surface;

[0016] The ceramic piece is annular and is arranged around the top and bottom surfaces of the pole. The top surface of the pole protrudes from the ceramic piece and is exposed to the external space, and the bottom surface of the pole is exposed to the internal space.

[0017] It is understandable that the battery cover usually contains at least two poles to correspond to the positive and negative poles of the battery cell respectively. Therefore, there are at least two through holes on the top cover to accommodate the positive pole and the negative pole respectively.

[0018] As a preferred technical solution of the present invention, in the external space, the vertical distance between the plane where the top surface of the pole is located and the plane where the surface of the top cover sheet is located is 1 to 2 mm, for example, 1 mm, 1.1 mm, 1.2 mm, 1.4 mm, 1.5 mm, 1.6 mm, 1.7 mm, 1.8 mm, 1.9 mm or 2 mm, etc., but is not limited to the listed values, and other values ​​not listed within the above numerical range are also applicable.

[0019] That is, the height of the terminal protruding from the through-hole into the external space is 1-2 mm. When using traditional plastic parts, the height of the terminal protruding from the top cover is usually more than 3 mm. Therefore, the use of ceramic parts in the present invention can reduce the thickness of the ceramic parts while maintaining the same structural strength, thereby improving the height and space utilization of the entire battery pack, and increasing energy by 1%-2%.

[0020] As a preferred technical solution of the present invention, in the external space, the top cover sheet is provided with a first fixing protrusion on the surface close to the edge of the through hole, and the ceramic part is provided with a first matching groove corresponding to the first fixing protrusion. By clamping the first fixing protrusion in the first matching groove, the ceramic part is fixedly connected to the top cover sheet.

[0021] As a preferred technical solution of the present invention, in the through hole, relative to the axial direction of the pole, the contact surface between the ceramic component and the top cover sheet is an inclined surface, and the inclined surface faces the top surface of the pole to support the ceramic component.

[0022] As a preferred technical solution of the present invention, the ceramic part is provided with a second fixing protrusion, and the pole is provided with a second matching groove corresponding to the second fixing protrusion. By clamping the second fixing protrusion in the second matching groove, the ceramic part is fixedly connected to the pole.

[0023] As a preferred technical solution of the present invention, the second matching groove is provided along the circumferential direction on the side surface between the top surface and the bottom surface of the pole.

[0024] As a preferred technical solution of the present invention, the battery cover plate also includes a sealing ring, which is arranged in the internal space and extends into the through hole, and is arranged between the pole and the top cover plate, and is sealed and connected to the pole and the top cover plate.

[0025] It can be understood that, in the through hole, when the ceramic component extends into the through hole, the sealing ring is also in contact with the ceramic component to form a sealed connection.

[0026] As a preferred technical solution of the present invention, the battery cover further includes a lower plastic member disposed within the internal space and having a portion disposed between the top cover sheet and the terminal post, thereby insulating the terminal post from the top cover sheet. That is, within the internal space, the lower plastic member includes a portion disposed between the top cover sheet and the terminal post, in a position not occupied by the sealing ring, to achieve insulation.

[0027] It should be noted that, in addition to the above structures and components, the battery cover plate usually also has explosion-proof holes (air leaks) and liquid injection holes (generally arranged on the top cover plate), as well as explosion-proof components (including explosion-proof valves, protective films, etc.) that match the explosion-proof holes, and sealing parts that match the injection holes; in addition, it can be understood that when the lower plastic pad is used as a positive electrode upper gasket and / or a negative electrode upper gasket, due to the larger coverage area, the lower plastic part should also be provided with openings corresponding to the through holes, explosion-proof holes and liquid injection holes of the top cover plate and structures corresponding to the openings, so that the poles, etc. can pass through the lower plastic part and be connected to the positive and negative poles of the battery cell; since the above structures and components do not directly affect the setting position and related structures of the ceramic parts described in the utility model, they can be reasonably adjusted and selected according to actual design and needs.

[0028] As a preferred technical solution of the present invention, the vertical distance between the top surface of the ceramic part and the plane where the surface of the top cover sheet is located is 0.5 to 1 mm, for example, 0.5 mm, 0.55 mm, 0.6 mm, 0.65 mm, 0.7 mm, 0.75 mm, 0.8 mm, 0.85 mm, 0.9 mm, 0.95 mm or 1 mm, etc., but is not limited to the listed values, and other values ​​not listed within the above numerical range are also applicable.

[0029] The present invention does not limit the specific material selection of the ceramic parts. The purpose is to satisfy the effect of the ceramic parts replacing traditional plastic parts. Ceramic materials with excellent insulation properties, mechanical properties and stability are preferred. Ceramic materials or ceramic raw materials with good processing properties are further preferred to facilitate processing and manufacturing. Reasonable adjustment and selection should be made according to actual design and needs. For example:

[0030] As a preferred technical solution of the present invention, the ceramic piece includes a boron bismuth glass ceramic piece.

[0031] Bismuth borate glass is a green, lead-free, low-melting-point glass solder. It has low softening and sealing temperatures and good chemical stability. This glass material is in powder form, making it easy to process and shape.

[0032] It should be noted that the material of the ceramic parts described in the present invention not only includes "ceramics", but also glass materials (preferably bismuth borate glass) can be used. Ceramics and glass are both inorganic non-metallic materials in materials science. Ceramics usually refer to crystalline materials formed by high-temperature sintering, while glass is amorphous. However, after the sintering process, glass powder can also form materials with ceramic properties, such as high hardness, high melting point and good mechanical properties. Therefore, parts formed by sintering glass powder can also be regarded as ceramic materials and ceramic parts.

[0033] As a preferred technical solution of the present invention, the lower plastic part includes a PPS plastic part.

[0034] The present invention does not limit the manufacturing method of the ceramic component and the assembly method of the ceramic cover plate, which can be reasonably adjusted and selected according to actual conditions and needs. For example:

[0035] When the ceramic component comprises a boron bismuth glass ceramic component, the manufacturing method of the boron bismuth glass ceramic component comprises first performing powder tableting or slurry coating molding, and then sintering to achieve vitrification to obtain the boron bismuth glass ceramic component.

[0036] Specifically, the powder tableting method includes: providing bismuth borate glass powder with uniform particle size, loading it into a customized mold, and using a powder tablet press to pressurize it at a pressure of 8 to 12 MPa, preferably 10 MPa, for 4 to 5 minutes to form a green body; after removing the green body using a demolding tool, sintering it to vitrify it and then cooling it to obtain the boron bismuth glass ceramic part.

[0037] Preferably, the mold is a metal mold in consideration of high pressure resistance and ease of demoulding.

[0038] As can be seen in the present invention, the powder tableting method is suitable for the resulting ceramic component to be used for placement and connection on flat surfaces, preferably in the form of a flat plate. After high-pressure pressing and sintering, the glass powder forms a dense ceramic structure with higher hardness and fatigue resistance, better able to withstand mechanical stress and prevent uneven force. This also facilitates a more stable fit between the ceramic component and the sealing ring, reducing the possibility of the sealing ring loosening and preventing electrolyte leakage.

[0039] Specifically, the slurry coating molding method includes: mixing bismuth borate glass powder with a solvent and an organic binder, adjusting the ratio of the binder according to the viscosity requirements, and stirring until a uniform slurry is formed; applying the slurry to the target part, sintering it, vitrifying it, and then cooling it to obtain the borobismuth glass ceramic part.

[0040] Preferably, the solvent comprises alcohol.

[0041] Preferably, the organic binder comprises polyvinyl alcohol.

[0042] Preferably, the coating method includes any one of brushing, spraying or knife coating.

[0043] Preferably, the coating is a multi-layer coating to ensure uniform coverage of complex surfaces.

[0044] Preferably, the slurry coating molding method is preceded by a preliminary heat treatment before sintering, so as to accelerate the volatilization of the binder and the preliminary sintering of the glass powder.

[0045] Preferably, the preliminary heat treatment is carried out in an oven.

[0046] As can be seen in the present invention, the slurry coating molding method is suitable for the placement and connection of the resulting ceramic component on complex surfaces or shapes, facilitating the formation of ceramic components on various top cover shapes. The sintered ceramic component exhibits excellent insulation properties, preventing short circuits between electrodes. The high hardness and wear resistance of the ceramic layer contribute to the overall mechanical properties of the battery top cover.

[0047] Compared with the existing technical solutions, the present invention has at least the following beneficial effects:

[0048] The present invention uses ceramic parts to replace the existing upper plastic parts, that is, the side (outside) of the top cover away from the battery cell is not provided with other plastic parts except the ceramic parts. By providing the ceramic parts, the insulation performance and stress conditions of traditional plastics can be improved, the mechanical strength, insulation performance and sealing performance of the battery cover can be effectively improved, and the problems such as loosening of the sealing ring due to uneven stress or mechanical fatigue of traditional plastic parts can be effectively solved. The manufacturing and use costs of ceramic parts are low, the process is simple, and the production costs can be reduced. Since ceramic parts replace plastic parts, the thickness (protruding height) of ceramic parts can be significantly lower than that of plastic parts while obtaining the same structural strength, which is conducive to reducing the height of the poles and improving the height space utilization of the entire battery pack, so that the energy is increased by 1% to 2%. BRIEF DESCRIPTION OF THE DRAWINGS

[0049] Figure 1 is an exploded schematic diagram of the battery cover of Example 1;

[0050] Figure 2 is a top view of the assembled battery cover of Example 1;

[0051] Figure 3 yes Figure 2 Schematic diagram of the cross-sectional structure along the AA direction;

[0052] Figure 4 yes Figure 3 An enlarged view of the positive electrode side in the figure;

[0053] In the figure: 10-top cover plate, 11-through hole, 12-explosion-proof hole, 13-liquid injection hole, 14-first fixing protrusion, 20-pole, 21-top surface, 22-bottom surface, 23-second matching groove, 30-ceramic part, 31-first matching groove, 32-second fixing protrusion, 40-sealing ring, 50-lower plastic part, 60-inclined surface, 70-explosion-proof component. DETAILED DESCRIPTION

[0054] The technical solution of the present utility model is further illustrated below through specific implementation methods.

[0055] Those skilled in the art should understand that the embodiments are only intended to help understand the present invention and should not be considered as specific limitations of the present invention.

[0056] Example 1

[0057] This embodiment provides a battery cover, such as Figures 1 to 4 Shown, including:

[0058] A top cover sheet 10, one side of which is designed to accommodate the battery cells. The side of the top cover sheet 10 away from the battery cells is the external space, and the side close to the battery cells is the internal space. Two through holes 11 are provided on the top cover sheet 10. In the external space, a first fixing protrusion 14 is provided on the surface of the top cover sheet 10 near the edge of the through hole 11.

[0059] The electrode 20 includes a positive electrode 20 and a negative electrode 20, each of which is disposed in a corresponding through hole 11 (i.e., the positive through hole and the negative through hole), and the two ends of the electrode 20 protrude into the external space and the internal space, respectively; the end surface of the electrode 20 at one end of the external space is a top surface 21, and the end surface of the electrode 20 at one end of the internal space is a bottom surface 22; a second mating groove 23 is circumferentially provided on the side surface between the top surface 21 and the bottom surface 22 of the electrode 20;

[0060] The ceramic member 30 is a boron bismuth glass ceramic member 30, which is arranged in the external space and extends into the through hole 11, and is arranged between the pole 20 and the top cover sheet 10, and is fixedly connected to the pole 20 and the top cover sheet 10, so that the pole 20 is fixed in the through hole 11 and insulated from the top cover sheet 10; the ceramic member 30 is annular, and the ceramic member 30 is surrounded by the top surface 21 and the bottom surface 22 of the pole 20. The top surface 21 of the pole 20 protrudes from the ceramic member 30 and is exposed to the external space, and the bottom surface 22 of the pole 20 is exposed to the internal space; and in the external space, the plane where the top surface 21 of the pole 20 is located is the same as the plane where the surface of the top cover sheet 10 is located. The shortest vertical distance is 1.6 mm; the ceramic component 30 is provided with a first matching groove 31 corresponding to the first fixing protrusion 14, and the ceramic component 30 is fixedly connected to the top cover sheet 10 by clamping the first fixing protrusion 14 in the first matching groove 31; the ceramic component 30 is also provided with a second fixing protrusion 32 corresponding to the second matching groove 23, and the ceramic component 30 is fixedly connected to the pole 20 by clamping the second fixing protrusion 32 in the second matching groove 23; in the through hole 11, relative to the axial direction of the pole 20, the contact surface between the ceramic component 30 and the top cover sheet 10 is an inclined surface 60, and the inclined surface 60 faces the top surface 21 of the pole 20 to support the ceramic component 30;

[0061] a sealing ring 40 disposed in the internal space and extending into the through hole 11, and disposed between the pole 20 and the top cover sheet 10, and forming a sealed connection with the pole 20, the top cover sheet 10, and the ceramic member 30 extending into the through hole 11;

[0062] The lower plastic member 50 is disposed in the internal space and in the space between the top cover sheet 10 and the pole 20 that is not occupied by the sealing ring 40 , so as to insulate the pole 20 from the top cover sheet 10 .

[0063] Comparative Example 1

[0064] This comparative example provides a battery cover, which does not use the ceramic part 30 of Example 1, but replaces the ceramic part 30 of Example 1 with an upper plastic part formed of PPS plastic particles. Except for the above, other conditions are exactly the same as those of Example 1.

[0065] After assembling the battery cover plates obtained in Example 1 and Comparative Example 1 into a battery for application, it can be seen that the present invention uses ceramic parts to replace the existing upper plastic parts, that is, the side (outside) of the top cover plate away from the battery cell is not provided with other plastic parts except the ceramic parts. By providing the ceramic parts, it is possible to improve the insulation performance and stress conditions of traditional plastics, effectively improve the mechanical strength, insulation performance and sealing performance of the battery cover, and effectively solve the problems of traditional plastic parts such as loose sealing rings due to uneven stress or mechanical fatigue, which can extend battery life and reduce safety risks. The manufacturing and use costs of ceramic parts are low, the process is simple, and production costs can be reduced. Since ceramic parts replace plastic parts, the thickness (protruding height) of ceramic parts can be significantly lower than that of plastic parts while achieving the same structural strength, which is conducive to reducing the height of the poles and improving the height space utilization of the entire battery pack, resulting in an energy increase of 1% to 2%.

[0066] The preferred embodiments of the present invention are described in detail above. However, the present invention is not limited to the specific details of the above embodiments. Within the technical concept of the present invention, various simple modifications can be made to the technical solution of the present invention, and these simple modifications all fall within the scope of protection of the present invention.

[0067] It should also be noted that the various specific technical features described in the above specific embodiments can be combined in any appropriate manner without contradiction. In order to avoid unnecessary repetition, the present invention will not further describe various possible combinations.

[0068] In addition, the various embodiments of the present invention may be arbitrarily combined, and as long as they do not violate the concept of the present invention, they should also be regarded as the contents disclosed by the present invention.

[0069] The preferred embodiments of the present invention are described in detail above. However, the present invention is not limited to the specific details of the above embodiments. Within the technical concept of the present invention, various simple modifications can be made to the technical solution of the present invention, and these simple modifications all fall within the scope of protection of the present invention.

[0070] It should also be noted that the various specific technical features described in the above specific embodiments can be combined in any appropriate manner without contradiction. In order to avoid unnecessary repetition, the present invention will not further describe various possible combinations.

[0071] In addition, the various embodiments of the present invention may be arbitrarily combined, and as long as they do not violate the concept of the present invention, they should also be regarded as the contents disclosed by the present invention.

Claims

1. A battery cover, characterized in that: include: A top cover sheet (10) and a pole (20); the side of the top cover sheet (10) away from the battery core is an external space, and the side close to the battery core is an internal space; the top cover sheet (10) is provided with a through hole (11); the pole (20) is provided in the through hole (11), and its two ends protrude toward the external space and the internal space respectively; The battery cover plate further comprises a ceramic component (30), which is arranged in the external space and extends into the through hole (11), and is arranged between the pole (20) and the top cover sheet (10), and is fixedly connected to the pole (20) and the top cover sheet (10), so that the pole (20) is fixed in the through hole (11) and insulated from the top cover sheet (10).

2. The battery cover according to claim 1, characterized in that: The end surface of the pole (20) at one end of the external space is a top surface (21), and the end surface at one end of the internal space is a bottom surface (22); The ceramic part (30) is annular and is arranged around the top surface (21) and the bottom surface (22) of the pole (20). The top surface (21) of the pole (20) protrudes from the ceramic part (30) and is exposed to the external space, and the bottom surface (22) of the pole (20) is exposed to the internal space.

3. The battery cover according to claim 2, characterized in that: In the external space, a vertical distance between a plane where the top surface (21) of the pole (20) is located and a plane where the surface of the top cover sheet (10) is located is 1 to 2 mm.

4. The battery cover according to claim 1, characterized in that: In the external space, the top cover sheet (10) is provided with a first fixing protrusion (14) on a surface close to the edge of the through hole (11), and the ceramic component (30) is provided with a first matching groove (31) corresponding to the first fixing protrusion (14). By clamping the first fixing protrusion (14) in the first matching groove (31), the ceramic component (30) is fixedly connected to the top cover sheet (10).

5. The battery cover according to claim 1 or 4, characterized in that: In the through hole (11), relative to the axial direction of the pole (20), the contact surface between the ceramic component (30) and the top cover plate (10) is an inclined surface (60), and the inclined surface (60) faces the top surface (21) of the pole (20) to support the ceramic component (30).

6. The battery cover according to claim 1 or 4, characterized in that: The ceramic component (30) is provided with a second fixing protrusion (32), and the pole (20) is provided with a second matching groove (23) corresponding to the second fixing protrusion (32). By clamping the second fixing protrusion (32) in the second matching groove (23), the ceramic component (30) and the pole (20) are fixedly connected.

7. The battery cover according to claim 6, characterized in that: The second matching groove (23) is arranged along the circumferential direction on the side surface between the top surface (21) and the bottom surface (22) of the pole (20).

8. The battery cover according to claim 1, characterized in that: The battery cover plate further includes a sealing ring (40), which is arranged in the internal space and extends into the through hole (11), and is arranged between the pole (20) and the top cover plate (10), and is sealed and connected to the pole (20) and the top cover plate (10).

9. The battery cover according to claim 1 or 8, characterized in that: The battery cover plate further comprises a lower plastic part (50), which is arranged in the internal space and has a portion arranged between the top cover plate (10) and the pole (20), so as to insulate the pole (20) from the top cover plate (10).

10. The battery cover according to claim 1, characterized in that: The vertical distance between the top surface of the ceramic piece (30) and the plane where the surface of the top cover sheet (10) is located is 0.5 to 1 mm.

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