Novel shell and secondary battery

Abstract

The utility model discloses a novel shell which comprises a side wall and a shell bottom cover, the central area of the shell bottom cover is an anti-explosion area, the area of the anti-explosion area is not larger than 1 / 2 of the area of the shell bottom cover, the thickness of the anti-explosion area is not larger than that of the shell bottom cover, and anti-explosion nicks are arranged in the anti-explosion area; according to the secondary battery provided by the utility model, a shell of the secondary battery comprises a side wall and a shell bottom cover, and the central area of the shell bottom cover is an explosion-proof area. After the explosion-proof area is arranged in the central area of the bottom of the shell, when the battery is subjected to thermal runaway, the explosion-proof area is exploded through the explosion-proof nicks and is not easy to block, so that the safety of the battery is integrally improved, and the processing and manufacturing cost of the shell is also reduced.

Description

Technical Field

[0001] The utility model belongs to the field of secondary batteries, and particularly relates to a novel housing and a secondary battery. Background Art

[0002] Secondary batteries have the advantages of high energy and power density, many cycle times, long storage time, clean and environmental protection, etc. Therefore, they are widely used in electronic devices such as digital cameras, computers, mobile phones, and power tools, and have broad application prospects in electric vehicles, electric bicycles, electric ships, and even large and medium-sized devices such as electric aircraft and energy storage devices.

[0003] With the rapid development and improvement of electric vehicle technology, electric vehicles have generally entered people's daily lives. Therefore, electric vehicles have higher requirements for the safety performance of secondary batteries that provide power for them. Especially when the battery has a thermal runaway, there should be no fire and explosion phenomena. To improve the safety performance of secondary batteries, an explosion-proof valve is usually set on the cover plate in the prior art. However, on the cover plate, the area available for setting the explosion-proof valve is very limited, especially for cylindrical batteries, and the ideal effect is often not achieved, resulting in fire and explosion. This requires adding a secondary explosion-proof mechanism (eccentric position, and a connecting piece is welded in the center) on the housing to strengthen the timely discharge of internal heat of the battery during thermal runaway to prevent the battery from catching fire and exploding. However, the inventor found that the explosion-proof mechanism at the eccentric position at the bottom of the housing is extremely prone to blockage during thermal runaway, and the forming and processing cost is extremely high, and the ideal explosion-proof effect and economic benefits cannot be achieved either.

[0004] Therefore, there is an urgent need for a novel housing and a secondary battery to improve the exhaust effect of secondary explosion-proof and reduce the processing and manufacturing cost. Summary of the Utility Model

[0005] The purpose of the utility model is to provide a novel housing and a secondary battery to avoid the blockage of the explosion-proof mechanism during secondary blasting, improve the safety performance of the secondary battery, and at the same time greatly reduce the processing and manufacturing cost.

[0006] To achieve the above purpose, the technical solution of the novel housing provided by the utility model is:

[0007] A novel housing includes a side wall and a housing bottom cover. The central area of the housing bottom cover is an explosion-proof area. The area of the explosion-proof area is not greater than 1 / 2 of the area of the housing bottom cover, and the thickness of the explosion-proof area is not greater than the thickness of the housing bottom cover. Explosion-proof marks are arranged in the explosion-proof area.

[0008] Further, the housing is a columnar structure with a single-side opening.

[0009] Further, the side wall of the housing and the housing bottom cover are integrally formed or sealed and connected by welding.

[0010] Further, the explosion-proof area is a circular groove-shaped structure integrally formed on the bottom cover of the housing.

[0011] Further, the explosion-proof area is composed of a first thinning area and a second thinning area, or the explosion-proof area is only composed of the first thinning area, or the explosion-proof area is only composed of the second thinning area. The first thinning area is arranged on the bottom surface of the bottom cover of the housing, and the second thinning area is arranged on the top surface of the bottom cover of the housing.

[0012] Further, the housing is formed by stamping or cold extrusion of sheet metal.

[0013] Further, the explosion-proof area is eccentrically arranged, and there is at least one explosion-proof area.

[0014] Further, there is at least one explosion-proof notch. When the number of explosion-proof notches is greater than or equal to 2, all the notches are concentrically or eccentrically arranged.

[0015] The beneficial effects of the present utility model are as follows:

[0016] For the bottom cover of the housing provided by the present utility model, the central area of the bottom cover of the housing is the explosion-proof area; after setting the explosion-proof area in the central area of the bottom of the housing of the present utility model, when the battery undergoes thermal runaway, the explosion-proof area explodes through the explosion-proof notches and is not easily blocked, thereby improving the safety of the battery as a whole and reducing the manufacturing cost of the housing at the same time.

[0017] The technical solution of the secondary battery provided by the present utility model is as follows:

[0018] A secondary battery includes a housing and an electric core, the electric core is accommodated inside the housing, and the housing is the housing in the above technical solution.

[0019] The beneficial effects of the present utility model are as follows:

[0020] For the secondary battery provided by the present utility model, the housing of the secondary battery includes a side wall and a bottom cover of the housing, and the central area of the bottom cover of the housing is the explosion-proof area. After setting the explosion-proof area in the central area of the bottom of the housing of the present utility model, when the battery undergoes thermal runaway, the explosion-proof area explodes through the explosion-proof notches and is not easily blocked, thereby improving the safety of the battery as a whole and reducing the manufacturing cost of the housing at the same time. Description of the Drawings

[0021] Figure 1 It is an exploded view of the structure of the secondary battery provided by the embodiment of the present application;

[0022] Figure 2 It is a schematic partial sectional structure view of the secondary battery provided by the embodiment of the present application along the center section;

[0023] Figure 3Schematic diagram of the three-dimensional structure of the novel housing provided by the embodiment of the present application;

[0024] Figure 4 Schematic diagram of the top view structure of the novel housing provided by the embodiment of the present application;

[0025] Figure 5 Schematic diagram of the structure of the novel housing cut along the center provided by the embodiment of the present application;

[0026] Figure 6 For Figure 5 Schematic diagram of the enlarged structure at position E in

[0027] Figure 7 For Figure 6 Schematic diagram of the structure in which the explosion-proof area consists of only the first thinning area in

[0028] Figure 8 For Figure 6 Schematic diagram of the structure in which the explosion-proof valve consists of only the second thinning area in

[0029] Figure 9 Schematic diagram of the bottom cover of the housing when the explosion-proof area is eccentrically designed.

[0030] Wherein: 1. Secondary battery; 11. Cover plate assembly; 111. Adapter piece; 12. Electric core; 121. First pole ear; 122. Second pole ear; 13. Housing; 131. Housing side wall; 132. Housing bottom cover; 1321. Explosion-proof area; 1321a. First thinning area; 1321b. Second thinning area; H0. Thickness of the housing bottom cover; H1. Thickness of the explosion-proof area. Detailed implementation manners

[0031] To solve the problems in the background art, the core inventive concept of the present utility model is that the central area of the housing bottom cover is an explosion-proof area. After setting the explosion-proof area in the central area of the bottom of the housing of the present utility model, when the battery undergoes thermal runaway, the explosion-proof area bursts through the explosion notch and is not easily blocked, thereby generally improving the safety of the battery and also reducing the manufacturing cost of the housing.

[0032] The following further describes the present utility model in detail with reference to embodiments.

[0033] Specific embodiment of the single cell provided by the present utility model:

[0034] Refer to Figures 1 to 2 , the housing 13 of the embodiment of the present utility model is cylindrical and has a single-sided opening to communicate with the internal accommodation space through the opening; the housing bottom cover 132 is used to connect the second pole ear 122 of the electric core 12 to output current outward through the housing 13.

[0035] Figure 1 AndFigure 2 The usage scenario of the housing 13 of this embodiment is shown. First, the battery cell 12 is electrically connected to the bottom cover 13 of the housing. More specifically, first, through the open end of the housing 13, the battery cell 12 is assembled into the housing 13 according to a certain polarity setting. By applying a certain pressure, the bottom cover 132 of the housing is closely attached to the second tab 122 of the battery cell 12, and then through welding, the bottom cover 132 of the housing is electrically connected to the battery cell 12, so as to output current outward.

[0036] Reference Figure 1 and Figure 2 As shown in and, the central area of the bottom cover 132 of the housing is an explosion-proof area 1321. In this embodiment, the explosion-proof area 1321 is arranged at the center of the bottom cover 132 of the housing. In some other embodiments, such as Figure 9 shown in, the explosion-proof area 1321 can deviate from the center position of the bottom cover 132 of the housing, and multiple explosion-proof areas 1321 can also be arranged; explosion-proof notches 13211 are arranged on the explosion-proof area 1321. When the secondary battery 1 is abused or used improperly, the pressure inside the secondary battery 1 increases. When the pressure value reaches a certain level, the explosion-proof notches 13211 on the explosion-proof area 1321 rupture, and the energy inside the secondary battery 1 is discharged in the form of gas in time, thereby preventing safety accidents such as fire or explosion of the secondary battery 1.

[0037] In order to achieve stepped explosion-proof and better explosion-proof effect, there are multiple explosion-proof notches 13211 on one explosion-proof area 1321. For example, Figure 9 shown in, multiple explosion-proof notches 13211 are concentrically arranged or the explosion-proof notches 13211 are not concentrically arranged. The thickness of each position where the explosion-proof notch 13211 is located is not equal to achieve multi-step explosion-proof, and the thickness of the position where the explosion-proof notch 13211 is located is less than the thickness of the explosion-proof area 1321.

[0038] Reference Figures 3 to 5 As shown in, the central area of the bottom cover 132 of the housing is an explosion-proof area 1321, and the area of the explosion-proof area 1321 ≤ 1 / 2 of the area of the bottom cover 132 of the housing. Specifically, considering the strength of the housing 13 and the exhaust rate during blasting, the area of the explosion-proof area 1321 is specifically set to ≤ 1 / 2 of the area of the bottom cover 132 of the housing. If the area of the explosion-proof area 1321 is set too large, the strength of the housing 13 will be insufficient, and the bottom cover 132 of the housing will be deformed and bulged during use, thus affecting the use performance of the secondary battery 1.

[0039] Reference Figures 3 to 8, the explosion-proof area 1321 is a groove-shaped structure in the central area of the bottom cover 132 of the housing. Accordingly, the thickness H1 of the explosion-proof area 1321 ≤ the thickness H0 of the bottom cover 132 of the housing. More specifically, the explosion-proof area 1321 is thinned in the central area of the bottom cover 132 of the housing. Considering the feasibility and reliability of manufacturing, the explosion-proof area 1321 is designed as a circular groove-shaped structure. In some other embodiments, the explosion-proof area 1321 can also be designed as a square or other polygonal shape.

[0040] As Figures 5 to 8 shown, the explosion-proof area 1321 is composed of a first thinning area 1321a and a second thinning area 1321b (as Figure 6 ), or the explosion-proof area 1321 is only composed of the first thinning area 1321a (as Figure 7 ), or the explosion-proof area 1321 is only composed of the second thinning area 1321b (as Figure 8 ). More specifically, when the explosion-proof area 1321 is composed of the first thinning area 1321a and the second thinning area 1321b, the explosion-proof area 1321 is thinned on the inner side and the outer side of the central area of the bottom cover 132 of the housing respectively; when the explosion-proof area 1321 is only composed of the first thinning area 1321a, the explosion-proof area 1321 is thinned on the outer side of the central area of the bottom cover 1321 of the housing; when the explosion-proof area 1321 is only composed of the second thinning area 1321b, the explosion-proof area 1321 is thinned on the inner side of the central area of the bottom cover 1321 of the housing.

[0041] Preferably, the explosion-proof area 1321 is composed of a first thinning area 1321a and a second thinning area 1321b (as Figure 6 ). When the explosion-proof area 1321 is composed of the first thinning area 1321a and the second thinning area 1321b, the explosion-proof indentation 13211 can be effectively protected from damage and the decay of the explosion-proof value caused by external contact.

[0042] Refer to Figures 3 to 8 , the housing side wall 131 and the housing bottom cover 132 are integrally formed or sealed and connected by welding.

[0043] Preferably, the housing side wall 131 and the housing bottom cover 132 are integrally formed.

[0044] Refer to Figures 3 to 8 , the housing 13 is formed by stamping or cold extrusion of sheet metal.

[0045] Preferably, the housing 13 is formed by cold extrusion process

[0046] Refer to Figures 3 to 8 , the explosion-proof indentation 13211 is arranged in the explosion-proof area 1321 and can be placed on the inner side or the outer side of the explosion-proof area 1321.

[0047] The present application also provides a secondary battery 1 using the novel housing 13, which includes a cover assembly 11, a battery cell 12, and the housing 13 as described above; after the battery cell 12 is welded to the bottom cover 132 of the housing, it outputs current outward.

[0048] Finally, it should be noted that the above are only the preferred embodiments of the present utility model and are not used to limit the present utility model. Although the present utility model has been described in detail with reference to the foregoing embodiments, for those skilled in the art, they can still make modifications to the technical solutions recorded in the foregoing embodiments without creative efforts, or perform equivalent replacements for some of the technical features. Any modifications, equivalent replacements, improvements, etc. made within the spirit and principle of the present utility model shall be included within the protection scope of the present utility model.

Claims

1. A new type of housing, characterized in that: It includes a side wall and a bottom cover of the housing. The central area of the bottom cover of the housing is an explosion-proof area. The area of the explosion-proof area is not greater than 1 / 2 of the area of the bottom cover of the housing, and the thickness of the explosion-proof area is not greater than the thickness of the bottom cover of the housing. Explosion-proof notches are provided in the explosion-proof area.

2. The novel housing according to claim 1, characterized in that: The housing is a columnar structure with a single-sided opening.

3. The novel housing according to claim 2, wherein: The side wall of the housing and the bottom cover of the housing are integrally formed or sealed and connected by welding.

4. The novel housing according to claim 3, wherein: The explosion-proof area is a groove-shaped structure integrally formed on the bottom cover of the housing.

5. The novel housing according to claim 4, wherein: The explosion-proof area is composed of a first thinning area and a second thinning area, or the explosion-proof area is only composed of the first thinning area, or the explosion-proof area is only composed of the second thinning area. The first thinning area is provided on the bottom surface of the bottom cover of the housing, and the second thinning area is provided on the top surface of the bottom cover of the housing.

6. The novel housing according to claim 5, wherein: The housing is formed by stamping or cold extrusion of sheet metal.

7. The novel housing according to claim 1, wherein: The explosion-proof area is eccentrically arranged, and there is at least one explosion-proof area.

8. The novel housing according to claim 7, characterized in that: There is at least one explosion-proof notch. When the number of explosion-proof notches is greater than or equal to 2, all the notches are concentrically or eccentrically arranged.

9. A secondary battery, comprising a housing and an electrode assembly, wherein the electrode assembly is received inside the housing, characterized in that: The housing is the housing described in any one of claims 1-8.

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