Novel housing and secondary battery

Abstract

The present application discloses a novel housing, comprising a side wall (131) and a housing bottom cover (13). The central region of the housing bottom cover (13) is an explosion-proof region (1321). The area of the explosion-proof region (1321) is not greater than 1 / 2 of the area of the housing bottom cover (13), and the thickness of the explosion-proof region (1321) is not greater than the thickness of the housing bottom cover (13). An explosion-proof notch (13211) is provided in the explosion-proof region (1321). After the explosion-proof region is provided in the central region of the bottom of the housing of the present application, when thermal runaway occurs in a battery, the explosion-proof region bursts by means of the explosion-proof notch, and blockage is not prone to occur, thereby improving the safety of the battery on the whole, and also reducing the processing and manufacturing costs of the housing.

Description

A new shell and secondary battery TECHNICAL FIELD

[0001] The utility model belongs to the field of secondary battery, especially a new shell and secondary battery. BACKGROUND

[0002] Secondary battery has the advantages of high energy and power density, many cycle times, long storage time, clean and environmental protection, etc., so it has been widely used in digital cameras, computers, mobile phones, electric tools and other electronic devices, and has a wide application prospect in electric vehicles, electric bicycles, electric ships and even electric aircraft and other electric vehicles and energy storage equipment and other large and medium-sized equipment.

[0003] With the rapid development and improvement of electric vehicle technology, electric vehicles have entered people's daily life. Therefore, electric vehicles have higher requirements for the safety performance of secondary batteries that provide power for them, especially when the battery is in thermal runaway, fire and explosion cannot occur. To improve the safety performance of the secondary battery, the prior art usually provides an explosion-proof valve on the cover plate, but the area available for setting the explosion-proof valve on the cover plate is very limited, especially for cylindrical batteries, which often does not achieve the desired effect, resulting in fire and explosion. This requires the addition of a secondary explosion-proof mechanism (eccentric position, center with adapter plate welding) on the shell to enhance the timely discharge of internal heat when the battery is in thermal runaway to prevent the battery from catching fire and exploding. However, the inventors found that the explosion-proof mechanism at the eccentric position of the bottom of the shell is prone to blockage when it is in thermal runaway, and the cost of forming processing is extremely high, and the desired explosion-proof effect and economic benefit cannot be achieved.

[0004] Therefore, a new shell and secondary battery are needed to improve the exhaust effect of secondary explosion and reduce the processing cost. UTILITY MODEL CONTENTS

[0005] The utility model aims to provide a new shell and secondary battery to avoid blockage of the explosion-proof mechanism during secondary explosion, improve the safety performance of the secondary battery, and significantly reduce the processing cost.

[0006] To achieve the above-mentioned purpose, the technical scheme of the new shell provided by the utility model is:

[0007] A new shell, comprising a side wall and a shell bottom cover, the center area of the shell 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 shell bottom cover, the thickness of the explosion-proof area is not greater than the thickness of the shell bottom cover, and the explosion-proof area is provided with explosion-proof marks.

[0008] Further, the shell is a single-sided opening cylindrical structure.

[0009] Further, the shell side wall is integrally formed with the shell bottom cover or is sealingly connected by welding.

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

[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 second thinning area, the first thinning area is arranged on the bottom surface of the shell bottom cover, and the second thinning area is arranged on the top surface of the shell bottom cover.

[0012] Further, the shell is formed by stamping or cold extrusion of a 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, and when the number of explosion-proof notches is greater than or equal to 2, all the notches are concentrically or eccentrically arranged.

[0015] The utility model discloses the beneficial effects are:

[0016] The utility model discloses a shell bottom cover, the shell bottom cover center area is explosion -proof area, after setting the explosion -proof area to the shell bottom center area of the utility model, when battery heat runaway occurs, explosion -proof area breaks through the explosion -proof notch, and it is difficult to block, thereby improve the security of battery as a whole, also reduced the processing manufacturing cost of shell.

[0017] The utility model discloses a secondary battery technical scheme is:

[0018] A secondary battery includes a shell and an electric core, the electric core is contained in the shell, and the shell is the shell in the technical scheme.

[0019] The utility model discloses the beneficial effects are:

[0020] The utility model discloses a secondary battery, the shell of secondary battery includes side wall and shell bottom cover, and the shell bottom cover center area is explosion -proof area, after setting the explosion -proof area to the shell bottom center area of the utility model, when battery heat runaway occurs, explosion -proof area breaks through the explosion -proof notch, and it is difficult to block, thereby improve the security of battery as a whole, also reduced the processing manufacturing cost of shell. DETAILED DESCRIPTION

[0021] Fig. 1 is an explosion view of the secondary battery according to the embodiment of the application;

[0022] Fig. 2 is a partial cross-sectional view of the secondary battery according to the embodiment of the application along the center;

[0023] Figure 3 is a schematic diagram of the three-dimensional structure of the novel shell provided in the embodiment of this application;

[0024] Figure 4 is a top view schematic diagram of the novel shell structure provided in the embodiment of this application;

[0025] Figure 5 is a schematic diagram of the structure of the novel shell provided in the embodiment of this application, cut along the center.

[0026] Figure 6 is an enlarged schematic diagram of the structure at point E in Figure 5;

[0027] Figure 7 is a schematic diagram of the structure in Figure 6 where the explosion-proof zone consists only of the first thinning zone;

[0028] Figure 8 is a schematic diagram of the explosion-proof valve in Figure 6 consisting only of the second thinning zone;

[0029] Figure 9 is a schematic diagram of the structure of the bottom cover of the shell when the explosion-proof zone is eccentrically designed.

[0030] Wherein: 1. Secondary battery; 11. Cover plate assembly; 111. Adapter piece; 12. Battery cell; 121. First tab; 122. Second tab; 13. Housing; 131. Housing side wall; 132. Housing bottom cover; 1321. Explosion-proof zone; 1321a. First thinning zone; 1321b. Second thinning zone; H0. Housing bottom cover thickness; H1. Explosion-proof zone thickness. Detailed Implementation

[0031] To address the problems in the background technology, the core inventive concept of this utility model is: the central area of ​​the bottom cover is an explosion-proof zone. By setting an explosion-proof zone in the central area of ​​the bottom of the casing of this utility model, in the event of thermal runaway, the explosion-proof zone will burst through the explosion-proof grooves and is less prone to blockage, thereby improving the overall safety of the battery and reducing the processing and manufacturing cost of the casing.

[0032] The present invention will be further described in detail below with reference to the embodiments.

[0033] Specific embodiments of the single-cell battery provided by this utility model:

[0034] Referring to Figures 1 and 2, the housing 13 of this embodiment is cylindrical with an opening on one side to connect to its internal accommodating space; the bottom cover 132 of the housing is used to connect to the second tab 122 of the battery cell 12 so as to output current to the outside through the housing 13.

[0035] Fig. 1 and Fig. 2 show the use of the shell 13 of the present embodiment, the electric core 12 is first electrically connected with the shell bottom cover 13, more specifically, first, through the open end of the shell 13, the electric core 12 is assembled into the shell 13 according to a certain polarity, by applying a certain pressure, the shell bottom cover 132 is tightly attached to the second lug 122 of the electric core 12, and then the shell bottom cover 132 is electrically connected with the electric core 12 by welding, thereby outputting current to the outside.

[0036] Referring to Fig. 1 and Fig. 2, the center area of the shell bottom cover 132 is the explosion-proof area 1321, in the present embodiment, the explosion-proof area 1321 is arranged at the center position of the shell bottom cover 132, in other embodiments, as shown in Fig. 9, the explosion-proof area 1321 can be offset from the center position of the shell bottom cover 132, and the explosion-proof area 1321 can also be arranged in multiple; The explosion-proof area 1321 is provided with explosion-proof notches 13211, when the secondary battery 1 is misused or improperly used, the pressure inside the secondary battery 1 rises, when the pressure value reaches a certain degree, the explosion-proof notches 13211 on the explosion-proof area 1321 break, timely discharging the energy inside the secondary battery 1 in the form of gas, thereby preventing the secondary battery 1 from catching fire or exploding and other safety accidents.

[0037] In order to realize gradient explosion-proof and better explosion-proof effect, a plurality of explosion-proof notches 13211 are arranged on one explosion-proof area 1321, as shown in Fig. 9, the plurality of explosion-proof notches 13211 are arranged concentrically or the explosion-proof notches 13211 are arranged non-concentrically, the thickness of each explosion-proof notch 13211 is not equal to realize multi-gradient explosion-proof, and the thickness of the position of the explosion-proof notch 13211 is less than the thickness of the explosion-proof area 1321.

[0038] Referring to Fig. 3 to Fig. 5, the center area of the shell bottom cover 132 is the explosion-proof area 1321, and the area of the explosion-proof area 1321 is ≤1 / 2 the area of the shell bottom cover 132. Specifically, considering the strength of the shell 13 and the exhaust rate when exploding, the area of the explosion-proof area 1321 is specially set to ≤1 / 2 the area of the shell bottom cover 132. If the area of the explosion-proof area 1321 is too large, it will cause the shell 13 to be insufficient in strength, and the shell bottom cover 132 will deform and bulge during use, thereby affecting the use performance of the secondary battery 1.

[0039] Referring to Fig. 3 to Fig. 8, the explosion-proof area 1321 is a groove-shaped structure in the center area of the shell bottom cover 132, and correspondingly, the thickness H1 of the explosion-proof area 1321 is ≤ the thickness H0 of the shell bottom cover 132. More specifically, the explosion-proof area 1321 is thinned in the center area of the shell bottom cover 132, considering the feasibility and reliability of manufacturing, the explosion-proof area 1321 is designed as a circular groove-shaped structure, in other embodiments, the explosion-proof area 1321 can also be designed as a square or other polygonal shape.

[0040] As shown in FIGS. 5-8, the explosion-proof area 1321 is composed of the first thinning area 1321a and the second thinning area 1321b (as shown in FIG. 6) or the explosion-proof area 1321 is only composed of the first thinning area 1321a (as shown in FIG. 7) or the explosion-proof area 1321 is only composed of the second thinning area 1321b (as shown in FIG. 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 center area of the shell bottom cover 132; 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 center area of the shell bottom cover 1321; 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 center area of the shell bottom cover 1321.

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

[0042] Referring to FIGS. 3-8, the shell side wall 131 is integrally formed with the shell bottom cover 132 or is sealingly connected by welding.

[0043] Preferably, the shell side wall 131 is integrally formed with the shell bottom cover 132.

[0044] Referring to FIGS. 3-8, the shell 13 is formed by sheet metal stamping or cold extrusion.

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

[0046] Referring to FIGS. 3-8, the explosion-proof notch 13211 is disposed in the explosion-proof area 1321 and can be placed inside the explosion-proof area 1321 or outside the explosion-proof area 1321.

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

[0048] Finally, it needs to be explained that the above is only the preferred embodiment of the present application, and is not used to limit the present application, although the present application is described in detail with reference to the foregoing embodiments, for those skilled in the art, it still can modify the technical solutions recorded in the foregoing embodiments without paying creative labor, or make equivalent replacement for part of the technical features. Any modification, equivalent replacement, improvement, etc. made within the spirit and principles of the present application shall be included in the protection scope of the present application.

Claims

A new type of housing, characterized in that: The shell comprises a side wall and a shell bottom cover, a center area of the shell bottom cover is an anti-explosion area, an area of the anti-explosion area is not greater than 1 / 2 of an area of the shell bottom cover, a thickness of the anti-explosion area is not greater than a thickness of the shell bottom cover, and an anti-explosion notch is arranged in the anti-explosion area. The new housing according to claim 1, characterized in that The shell is a single-side opening columnar structure. The new housing according to claim 2, characterized in that The shell side wall is integrally formed with the shell bottom cover or is sealingly connected through welding. The new housing according to claim 3, characterized in that The anti-explosion area is a groove-shaped structure integrally formed on the shell bottom cover. The new housing according to claim 4, characterized in that: The anti-explosion area is composed of a first thinning area and a second thinning area, or the anti-explosion area is composed of only the first thinning area or only the second thinning area, the first thinning area is arranged on a bottom surface of the shell bottom cover, and the second thinning area is arranged on a top surface of the shell bottom cover. The new housing according to claim 5, characterized in that The shell is formed by stamping or cold extrusion of a sheet metal. The new housing according to claim 1, characterized in that The anti-explosion area is eccentrically arranged, and there is at least one anti-explosion area. The new housing according to claim 7, characterized in that There is at least one anti-explosion notch, and when the number of the anti-explosion notches is greater than or equal to 2, all the notches are concentrically or eccentrically arranged. A secondary battery includes a case and an electrode group accommodated inside the case, characterized by: The shell is the shell according to any one of claims 1-8.

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