Battery shell, single battery and battery pack

Abstract

The utility model relates to a battery shell, a single battery and a battery pack. The battery shell comprises a top side cover plate and a battery cell shell used for assembling a positive terminal, and the top side cover plate is welded to a top shell opening formed in the top of the battery cell shell; the top side cover plate is in a flat plate shape, the top shell opening of the battery cell shell is provided with a first step section which is formed by circumferentially expanding outwards and bending, and the top side cover plate abuts against and is welded with the first step section. According to the invention, different from the existing assembly structure of the shell and the top cover plate, the positive terminal is specifically assembled on the battery cell shell instead of the top side cover plate; meanwhile, the top side cover plate is of a flat-plate-shaped structure, it means that the manufacturing process of the top side cover plate is relatively simple, complex molds and machining equipment are not needed, in the production process, the forming speed of the top side cover plate is high, the quality is easy to control, the rejection rate in the production process can be reduced, and the production cost is reduced.

Description

Technical Field

[0001] The utility model relates to the technical field of batteries, and in particular to a battery shell, a single battery and a battery pack. Background Art

[0002] Lithium-ion power batteries are currently widely used in the new energy vehicle industry. The manufacturing process for battery cells is complex, requiring a series of precise steps including pulping, coating, cold pressing, slitting, winding, baking, liquid injection, formation, and secondary liquid injection. Finally, laser welding is used to seal the top cover to the cell casing.

[0003] However, after the actual welding of the battery cell casing and the top cover plate, it was found that the existing top cover plate usually needs to be punched in itself to assemble the pole terminals; or some bending structures need to be set to better assemble and weld. Such a setting requires complex curved surfaces or concave and convex shapes, which requires complex molds and processing equipment, resulting in production costs and is not conducive to large-scale production. There is room for improvement. Utility Model Content

[0004] In order to overcome at least one of the above-mentioned defects of the prior art, according to one aspect of the present invention, a battery casing is provided, comprising a top cover plate and a cell casing for assembling a positive terminal, wherein the top cover plate is welded to a top casing opening provided at the top of the cell casing;

[0005] The top cover plate is in a flat plate shape, and a first stage is formed by bending and expanding circumferentially at the top shell opening of the battery cell shell. The top cover plate abuts against and is welded to the first stage.

[0006] In one embodiment of the present application, the first stage is arranged vertically.

[0007] In one embodiment of the present application, it further includes a bottom cover plate, wherein the bottom cover plate is welded to a bottom shell opening provided at the bottom of the battery cell shell;

[0008] The bottom cover is in a flat plate shape, and the bottom shell opening of the cell housing has a second stage formed by circumferentially expanding and bending. The bottom cover abuts against and is welded to the second stage of the cell housing.

[0009] In one embodiment of the present application, the second stage is extended in a vertical direction.

[0010] In one embodiment of the present application, the first stage is tilted outward.

[0011] In one embodiment of the present application, the bending angle of the first stage is α, and the bending angle α is the angle between the inclined extension direction of the first stage and the vertical direction, and 0≤α<90°.

[0012] In one embodiment of the present application, the circumferential side edges of the top cover plate are bent inward to form an inclined top cover welding section, the first stage is inclined outward, and the outer side surface of the top cover welding section and the inner side surface of the first stage are abutted and welded.

[0013] In one embodiment of the present application, the bending angle of the first stage is α, and the bending angle α is the angle between the inclined extension direction of the first stage and the vertical direction, and 0≤α<90°;

[0014] Assume that the bending angle of the top cover welding section is β, and the bending angle β is the angle between the extension direction of the top cover welding section and the vertical direction, and β=α.

[0015] In one embodiment of the present application, an outwardly slanted expansion section is provided between the first stage and the battery cell housing.

[0016] According to another aspect of the present application, a single cell is provided, comprising the above-mentioned battery housing and a positive terminal, wherein the positive terminal is provided in the battery housing, and the battery housing serves as a negative electrode.

[0017] According to another aspect of the present application, a battery pack is provided, comprising the above-mentioned single cell battery.

[0018] In summary, the battery housing, single cell, and battery pack provided by the present invention have the following technical effects:

[0019] In this application, unlike the existing assembly structure of the housing and top cover, the positive terminal is specifically assembled on the battery cell housing rather than on the top cover. Furthermore, the top cover is a flat plate, which means that the manufacturing process for the top cover is relatively simple and does not require complex molds and processing equipment. During the production process, the top cover is formed quickly and the quality is easy to control, which can reduce the scrap rate and production costs during the production process. Furthermore, there is no need for complex curved or concave-convex shapes, which shortens the mold manufacturing cycle and reduces costs, facilitating large-scale production. BRIEF DESCRIPTION OF THE DRAWINGS

[0020] Figure 1 This is a schematic structural diagram of a battery housing according to an embodiment of the present utility model;

[0021] Figure 2 A cross-sectional view of the internal structure of a battery housing according to an embodiment of the present invention;

[0022] Figure 3 A cross-sectional view of the internal structure of a battery housing according to another embodiment of the present invention;

[0023] Figure 4A cross-sectional view of the internal structure of a battery housing according to another embodiment of the present invention;

[0024] Figure 5 A cross-sectional view of the internal structure of a battery housing according to another embodiment of the present invention;

[0025] Figures: 1-top cover, 11-top cover welding section, 2-cell casing, 21-first stage, 22-outward expansion section, 23-second stage, 3-positive terminal, 4-square battery cell, 5-accommodation space, 6-bottom cover. DETAILED DESCRIPTION

[0026] For better understanding and implementation, the technical solutions in the embodiments of the present invention will be clearly and completely described below in conjunction with the accompanying drawings in the embodiments of the present invention.

[0027] In the description of the present invention, it should be noted that the terms "upper", "lower", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inside", "outside", etc., indicating directions or positional relationships, are based on the directions or positional relationships shown in the accompanying drawings. They are only for the convenience of describing the present invention and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific direction, be constructed and operated in a specific direction. Therefore, they cannot be understood as limiting the present invention.

[0028] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as those commonly understood by those skilled in the art in the art of the present invention. The terms used herein in the specification of the present invention are only for the purpose of describing specific embodiments and are not intended to limit the present invention.

[0029] See Figure 1-Figure 5 This application discloses a battery housing and a battery pack including the battery housing.

[0030] At present, the existing top cover plate usually needs to be punched in itself to assemble the pole terminal; or some bending structures need to be set for better assembly and welding. Such a setting requires complex curved surfaces or concave and convex shapes, which requires complex molds and processing equipment, resulting in production costs and is not conducive to large-scale production. There is room for improvement.

[0031] Therefore, the present application improves the structure of the battery housing to solve the above-mentioned problems.

[0032] like Figure 2As shown, the present application discloses a specific embodiment. The battery casing includes a top cover plate 1 and a cell shell 2 for assembling a positive terminal 3. The top cover plate 1 is welded to a top shell opening provided on the top of the cell shell 2. The top cover plate 1 is flat, and the top shell opening of the cell shell 2 has a first stage 21 formed by circumferential outward expansion and bending. The top cover plate 1 and the first stage 21 are abutted and welded.

[0033] In this application, unlike the existing assembly structure of the housing and the top cover, the positive terminal 3 is specifically assembled on the battery cell housing 2 rather than on the top cover 1. At the same time, the top cover 1 is a flat plate, which means that the manufacturing process of the top cover 1 is relatively simple and does not require complex molds and processing equipment. During the production process, the top cover 1 is formed quickly and the quality is easy to control, which can reduce the scrap rate in the production process and lower production costs. At the same time, there is no need for complex curved or concave-convex shapes, which makes the mold manufacturing cycle short and the cost low, which is conducive to large-scale production.

[0034] More importantly, the flat surface of the top cover plate 1 facilitates uniform sealing pressure when sealing against the cell housing 2, ensuring the sealing effectiveness of the sealant or seal ring, and reducing the incidence of battery leakage, short circuits, or electrolyte leaks caused by poor sealing. Furthermore, the flat top cover plate 1 has a simple structure without complex concave and convex shapes, making it better able to withstand pressure from above. It also cooperates with the cell housing 2 to provide a more stable overall battery structure, making it less susceptible to distortion or deformation.

[0035] Specifically, the first stage 21 is arranged vertically. In this application, the vertically arranged first stage 21 is relatively easy to form during the manufacturing process. For example, the first stage 21 can be quickly formed at the top shell opening of the battery cell housing 2 through processes such as stamping and bending, thereby improving production efficiency. Furthermore, during assembly, the clear position and shape of the first stage 21 facilitates and simplifies the installation of the top cover plate 1, reducing assembly difficulty and error rates.

[0036] like Figure 3Specifically, the battery case further includes a bottom cover plate 6 welded to the bottom opening of the cell housing 2. The bottom cover plate 6 is flat and has a second step 23 formed by bending and expanding circumferentially at the bottom opening of the cell housing 2. The bottom cover plate 6 abuts against and is welded to the second step 23 of the cell housing 2. This arrangement provides the flat bottom cover plate 6 with good rigidity, evenly distributing pressure from all directions and protecting the internal cells and other components. Furthermore, the weld between the flat bottom cover plate 6 and the second step 23 forms a relatively flat sealing surface. During the welding process, the flat surface facilitates uniform weld strength and improves sealing performance. This sealing structure effectively prevents electrolyte leakage and external impurities from entering the battery, ensuring safe operation. Furthermore, the flat design is simple and easy to manufacture. It can be quickly produced using conventional processing methods such as stamping and cutting, reducing production costs. The simple structure also facilitates quality control and reduces the rate of defective products during production.

[0037] As can be seen from the accompanying drawings, in the above embodiment, the battery housing has a top shell opening and a bottom shell opening distributed vertically up and down, as well as a flat top cover plate 1 and a flat bottom cover plate 6. Such a structure can further speed up production and reduce production costs.

[0038] Specifically, such as Figure 3 As shown, the second stage 23 extends vertically. This arrangement allows the vertically extending second stage 23 to be manufactured using simple stamping and bending processes, resulting in high production efficiency. Furthermore, its well-defined shape and dimensions facilitate assembly of the bottom cover plate 6, reducing assembly difficulty and error rates. This design facilitates automated production, increasing production scale and ensuring quality stability.

[0039] like Figure 4As shown, specifically, the first stage 21 is tilted outward. In this specific embodiment, the first stage 21 tilted outward, combined with the flat top cover 1, provides an inclined support surface for the top cover 1. During the installation process, the top cover 1 can gradually slide into the correct position along this inclined surface to achieve fast and accurate positioning. Therefore, this design enables the top cover 1 to automatically align with the top shell opening of the battery cell casing 2 during installation, reducing the adjustment and calibration work during the installation process. In addition, a wedge-shaped structure is formed between the inclined first stage 21 and the flat top cover 1. When the two are connected by welding, this wedge-shaped structure can increase the contact area of ​​the welding surface and improve the strength and stability of the welding. At the same time, the outward-inclined first stage 21 can be realized through simple stamping, bending and other processes during the manufacturing process. The flat top cover plate 1 is also easy to process and manufacture, which reduces production costs. During the assembly process, this design makes the installation of the top cover plate 1 more convenient and quick, and improves production efficiency. For example, automated assembly equipment can be used for installation to reduce errors and labor intensity of manual operations.

[0040] Specifically, the bending angle of the first stage 21 is α, and the bending angle α is the angle between the inclined extension direction of the first stage 21 and the vertical direction, and 0<α<90°. For example, the bending angle α can be specifically 30°, 45° or 60°, etc. Or, for example, the bending angle α can be specifically 0<α<90° and other verticals within this range. By reasonably setting the bending angle α, the first stage 21 is more tightly combined with the top cover plate 1, and the structural stability of the top of the battery is enhanced. This structure can effectively resist external impact, vibration and pressure, and reduce the risk of deformation, damage or leakage of the battery during use. Moreover, within the range of 0<α<90°, a suitable angle can be selected according to actual needs to achieve the best sealing performance. Good sealing performance can ensure the stability of the internal chemical environment of the battery, improve the safety and reliability of the battery, and reduce the possibility of battery performance degradation and failure due to poor sealing.

[0041] In practical applications, the bending angle α can be adjusted to meet the design requirements and application scenarios of different battery types. For example, for small, portable batteries, a smaller angle α can be selected to save space; for large, high-power batteries, a larger angle α can be selected to improve structural strength and sealing performance.

[0042] like Figure 5 As shown, specifically, the circumferential side of the top cover plate 1 is bent inward to form an inclined top cover welding section 11, the first stage 21 is inclined outward, and the outer side surface of the top cover welding section 11 and the inner side surface of the first stage 21 are abutted and welded.

[0043] In specific applications, an inward-bent top cover welding section 11 and an outward-bent first stage 21 are formed on the shell opening of the battery cell casing 2, and the top cover welding section 11 and the first stage 21 are used for positioning and assembly. Specifically, the outer side surface of the top cover welding section 11 and the inner side surface of the first stage 21 are used for positioning and assembly. Since the top cover welding section 11 and the first stage 21 are both specifically bent and the area of ​​the facing surfaces of the two is large, the area used for positioning and assembly will also be relatively strained, so that the battery cell casing 2 and the top side cover 1 are easier to position and assemble, so as to prevent the battery cell casing 2 and the top side cover 1 from tilting or shaking during welding, thereby preventing the occurrence of poor welding problems.

[0044] Furthermore, the joint strength is enhanced, ensuring a close fit between the top cover weld section 11 and the first stage 21, increasing the weld area and thus improving the strength of the connection. This helps maintain structural integrity when subjected to external forces or internal pressure, reducing the risk of deformation or damage caused by a weak connection. Furthermore, when the top cover weld section 11 and the first stage 21 are tightly aligned, a sealed weld joint is formed. This sealing performance is crucial for applications that require preventing gas, liquid, or dust leakage, and improves overall sealing performance.

[0045] Specifically, the top cover plate 1 and the battery cell housing 2 can be made of metal materials.

[0046] Specifically, the bending angle of the first stage 21 is α, and the bending angle α is the angle between the extension direction of the first stage 21 and the vertical direction, and 0≤α<90°; the bending angle of the top cover welding section 11 is β, and the bending angle β is the angle between the extension direction of the top cover welding section 11 and the vertical direction, and β=α.

[0047] Since the bending angles of the first stage 21 and the top cover welding section 11 are the same, after welding, the force on the structure in all directions is more evenly distributed. When subjected to external loads, the force can be evenly distributed along the weld, reducing local stress concentration, thereby reducing the risk of deformation or damage to the structure. Moreover, this uniform force characteristic is particularly important for structures that withstand dynamic loads or vibrations, and can improve the fatigue life and reliability of the structure. At the same time, the same bending angle allows the top cover and the shell to fit better at the weld, increasing the effective area of ​​the weld. This helps to improve the strength of the weld, making the connection more secure and reliable; and the increase in welding strength can ensure that during long-term use, the top cover 1 and the battery cell shell 2 will not easily separate, ensuring the integrity of the structure.

[0048] Specifically, an outwardly angled expansion section 22 is provided between the first stage 21 and the cell housing 2. This expansion section 22 provides a better working space for welding. When welding the first stage 21 to the top cover welding section 11, workers can more easily access the weld area, improving welding quality and efficiency. Furthermore, the expansion section 22 provides positioning and support, making the welding process more stable and reducing the occurrence of welding defects.

[0049] Specifically, both the top cover welding section 11 and the first stage 21 are constructed with straight segments. This structure evenly distributes stress across the weld after welding. Compared to curved or complex-shaped welds, straight segments more easily achieve a uniform stress distribution, reducing the risk of localized stress concentration. Furthermore, the weld area of ​​a straight segment is relatively large and regular, facilitating a more secure weld connection. Furthermore, during the welding process, the solder can better fill the weld area, ensuring weld quality.

[0050] Specifically, the battery housing is a square housing. Square housings allow for tighter arrangement during storage and installation, especially in limited spaces. Compared to cylindrical batteries, square batteries can better adapt to the internal spaces of various device shapes, reducing space waste. Furthermore, the regular shape of square batteries facilitates modular design, allowing multiple square batteries to be combined into different battery packs to meet the power and energy requirements of different devices.

[0051] Another object of the present application is to provide a single battery comprising the above-mentioned battery casing.

[0052] Specifically, the single cell battery further includes a positive terminal 3, which is located in the battery housing, with the battery housing serving as the negative electrode. Using the battery housing as the negative electrode eliminates the need for an additional independent negative electrode component, simplifying the overall battery structure and helping to reduce manufacturing costs and assembly complexity. Furthermore, since no independent negative electrode structure is required, more space is available within the battery to accommodate electrode materials and electrolyte, thereby increasing the battery's energy density.

[0053] Specifically, the single battery also includes a square battery cell 4, and a receiving space 5 for assembling the square battery cell 4 is formed between the top cover plate 1 and the battery cell shell 2. The receiving space 5 provides a specific installation position for the square battery cell 4, so that it can be stably placed inside the battery. This helps prevent the battery cell from moving or shaking during battery use, and reduces the risk of loosening or damage to the internal connection due to battery cell displacement. In addition, the receiving space 5 formed by the top cover plate 1 and the battery cell shell 2 can provide certain physical protection for the square battery cell 4. It can prevent external objects from directly impacting, squeezing or scratching the battery cell, reducing the possibility of damage to the battery cell.

[0054] Another object of the present application is to provide a battery pack comprising the aforementioned single cell. In this battery pack, an inward-curved top cover welding section 11 is formed on the top cover plate 1, and an outward-curved first stage 21 is formed on the shell opening of the cell housing 2. Positioning and assembly are performed using the top cover welding section 11 and the first stage 21, specifically using the facing surfaces of the top cover welding section 11 and the first stage 21. Due to the large facing surface area of ​​the top cover welding section 11 and the first stage 21, the area used for positioning and assembly is also relatively large, effectively increasing the area used for positioning and assembly between the cell housing 2 and the top cover plate 1, thereby preventing tilting or shaking between the cell housing 2 and the top cover plate 1, and thus preventing welding defects.

[0055] The technical means disclosed in the present invention are not limited to those disclosed in the above-mentioned embodiments, but also include technical solutions composed of any combination of the above-mentioned technical features. It should be noted that those skilled in the art can make various improvements and modifications without departing from the principles of the present invention, and such improvements and modifications are also considered to be within the scope of protection of the present invention.

Claims

1. A battery housing, characterized in that: It comprises a top cover plate (1) and a battery cell shell (2) for assembling a positive terminal (3), wherein the top cover plate (1) is welded to a top shell opening provided at the top of the battery cell shell (2); The top cover plate (1) is in the shape of a flat plate, and the top shell opening of the battery cell shell (2) has a first stage (21) formed by circumferentially expanding and bending. The top cover plate (1) and the first stage (21) are abutted against and welded.

2. A battery casing according to claim 1, characterized in that: The first stage (21) is arranged vertically.

3. A battery casing according to claim 1 or 2, characterized in that: It also includes a bottom cover plate (6), which is welded to a bottom shell opening provided at the bottom of the battery cell shell (2); The bottom cover plate (6) is in the shape of a flat plate, and the bottom shell opening of the battery cell housing (2) has a second stage (23) formed by circumferentially expanding and bending. The bottom cover plate (6) abuts against and is welded to the second stage (23) of the battery cell housing (2).

4. A battery casing according to claim 3, characterized in that: The second stage (23) is extended in the vertical direction.

5. The battery casing according to claim 1, characterized in that: The first stage (21) is arranged to be inclined outwards.

6. A battery housing according to claim 5, characterized in that The bending angle of the first stage (21) is α, and the bending angle α is the angle between the inclined extension direction of the first stage (21) and the vertical direction, and 0≤α<90°.

7. The battery casing according to claim 1, characterized in that: The circumferential side of the top cover plate (1) is bent inward to form an inclined top cover welding section (11), the first stage (21) is inclined outward, and the outer side surface of the top cover welding section (11) and the inner side surface of the first stage (21) are abutted and welded.

8. A battery housing according to claim 7, characterized in that The bending angle of the first stage (21) is α, and the bending angle α is the angle between the inclined extension direction of the first stage (21) and the vertical direction, and 0≤α<90°; Assume that the bending angle of the top cover welding section (11) is β, and the bending angle β is the angle between the extension direction of the top cover welding section (11) and the vertical direction, and β=α.

9. A battery casing according to any one of claims 1, 2, 4-8, characterized in that: An outwardly slanted expansion section (22) is provided between the first stage (21) and the battery cell housing (2).

10. A single cell battery, characterized in that: The invention comprises a battery casing according to any one of claims 1 to 9, and further comprises a positive terminal (3), wherein the positive terminal (3) is provided in the battery casing, and the battery casing serves as a negative electrode.

11. A battery pack, characterized in that: The invention comprises a single battery according to claim 10.

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