Explosion-proof valve double-opening power battery structure

Abstract

The application discloses a power battery structure with double-opened explosion-proof valves, which comprises a shell, a top cover and a core package. The top cover comprises a positive electrode top cover and a negative electrode top cover, and the positive electrode top cover and the negative electrode top cover are symmetrically arranged on the left and right sides of the shell. An explosion-proof valve is arranged on each of the positive electrode top cover and the negative electrode top cover, and a connecting rod assembly is connected between the two explosion-proof valves. The power battery structure has high safety performance, can realize double-opened explosion-proof valves, and solves the problem that the existing multiple explosion-proof valves cannot be simultaneously opened.

Description

TECHNICAL FIELD

[0001] The application belongs to the technical field of power batteries, and particularly relates to a power battery structure with double-opening explosion-proof valves. BACKGROUND

[0002] With the rapid development of electric vehicles, the technology of batteries is also constantly breaking through, and safety performance is the top priority in the research and production of lithium batteries. Due to the electrochemical characteristics of lithium batteries, when the square lithium battery is used for a long time or is in a high-temperature environment for a long time, the battery deteriorates seriously, and thermal runaway may occur, resulting in an increase in the internal pressure of the battery. The existence of the explosion-proof valve can prevent explosion and reduce the safety risk of the battery.

[0003] CN215869506U discloses a square lithium battery with double explosion-proof valves and high safety, which increases an explosion-proof valve at the bottom of the shell to form a double explosion-proof valve structure, so as to better prevent explosion. CN217956063U discloses a cell shell structure assembly, which sets multiple explosion-proof valves on the top cover to reduce safety risks.

[0004] The above two prior arts both envisage a cell structure with multiple explosion-proof valves, but in actual product application, when the battery pack fails, one of the explosion-proof valves is usually opened first, the internal pressure of the cell is rapidly reduced, and the second explosion-proof valve cannot be opened, resulting in the redundancy design of the multiple explosion-proof valves.

[0005] Therefore, it is necessary to provide a power battery structure with high safety performance to overcome the above defects. SUMMARY

[0006] In view of the deficiencies in the prior art, the purpose of the present application is to provide a power battery structure with double-opening explosion-proof valves. The power battery structure has high safety performance and can realize double-opening explosion-proof valves, solving the problem that multiple explosion-proof valves in the prior art cannot be opened simultaneously.

[0007] To achieve the above purpose, the present application realizes the following technical scheme:

[0008] A power battery structure with double-opening explosion-proof valves comprises a shell, a top cover and a cell pack. The top cover comprises a positive electrode top cover and a negative electrode top cover, which are symmetrically arranged on the left and right sides of the shell. The positive electrode top cover and the negative electrode top cover are both provided with explosion-proof valves, and a connecting rod assembly is connected between the two explosion-proof valves.

[0009] Preferably, the connecting rod assembly is arranged close to the upper part of the shell.

[0010] Further preferably, two said explosion-proof valves are symmetrically arranged on said positive electrode top cover and said negative electrode top cover, and both of said explosion-proof valves are arranged close to the upper part of said shell.

[0011] Further preferably, said elastic buffer has a deformation amount in the length direction of said shell, and said elastic buffer is in a natural extension state or a stretched state.

[0012] Preferably, said top cover further comprises a connecting cover plate, two ends of said connecting cover plate are fixedly connected with the upper ends of said positive electrode top cover and said negative electrode top cover respectively, the top surface and the left and right side surfaces of said shell are all open, and the top surface opening of said shell is in line with said connecting cover plate.

[0013] Further preferably, a boss is arranged at the top surface opening of said shell, and the upper surface of said boss is closely attached to the lower surface of said connecting cover plate.

[0014] Further preferably, said shell is integrally bent and formed.

[0015] Preferably, the top part of said core package is provided with a space for avoiding the connection assembly, and the top elevation of said core package is not lower than the top elevation of said connection assembly.

[0016] Preferably, the top cover and the shell are connected by a penetration welding process.

[0017] Compared with the prior art, the present application has the following advantages and beneficial effects:

[0018] The present application is provided with one explosion-proof valve on the top cover of each of the left and right sides of the shell, and two explosion-proof valves are connected by a connecting rod assembly, so that when one explosion-proof valve is opened, the other explosion-proof valve will be opened simultaneously under the linkage of the connecting rod assembly, thereby solving the problem that the existing multiple explosion-proof valves cannot be opened simultaneously.

[0019] The connecting rod assembly of the present application comprises an elastic buffer, which can provide a certain deformation buffer; when the core package is expanded due to heating or other factors (without thermal runaway), the distance between the two top covers will increase, and if the length of the connecting rod assembly cannot be adjusted, the explosion-proof valve will be opened under the pulling of the connecting rod assembly, and the addition of the elastic buffer can provide adaptive extension, thereby avoiding the mis-opening of the explosion-proof valve due to the unadjustable length of the connecting rod assembly; in addition, in order to better assemble the top cover, the distance between the positive electrode top cover and the negative electrode top cover needs to be properly widened outward, and therefore the elastic buffer can provide a certain deformation amount.

[0020] The U-shaped avoiding space is designed on the top of the core package to avoid reducing the capacity density of the battery due to the setting of the connecting rod assembly.

[0021] The shell can be formed by bending, and the shell is easy to manufacture, has high yield and low cost, avoids the internal stress problem of the shell, solves the expansion of the shell, and greatly reduces the risk of welding mark failure after welding. BRIEF DESCRIPTION OF DRAWINGS

[0022] Figure 1 It is a schematic diagram of the three-dimensional structure of the power battery structure of the application;

[0023] Figure 2 It is a schematic diagram of the top cover structure of the power battery structure of the application;

[0024] Figure 3 It is a schematic diagram of the shell structure of the power battery structure of the application;

[0025] Figure 4 It is a schematic diagram of the cross-sectional structure of the power battery structure of the application.

[0026] BRIEF DESCRIPTION OF DRAWINGS: 1-shell; 2-top cover; 3-core package; 4-connecting rod assembly; 11-open; 12- boss; 21-positive electrode top cover; 22-negative electrode top cover; 23-connection cover plate; 24-explosion-proof valve; 31-avoiding space; 41-connecting rod; 42-elastic buffer. DETAILED DESCRIPTION

[0027] In order for those skilled in the art to better understand the technical solutions of the present application, the preferred embodiments of the present application will be described below in combination with specific embodiments, but it should be understood that the drawings are only used for exemplary description and cannot be understood as a limitation of the present patent; in order to better illustrate the present embodiment, some components in the drawings may be omitted, enlarged or reduced, and do not represent the actual product size; for those skilled in the art, it is understandable that some well-known structures and their descriptions in the drawings may be omitted. The positional relationship described in the drawings is only used for exemplary description and cannot be understood as a limitation of the present patent.

[0028] In order to solve the problem that the existing multiple explosion-proof valves cannot be opened at the same time, the present application provides a power battery structure with double-opening explosion-proof valve, which comprises a shell 1, a top cover 2 and a core package 3.

[0029] As Figure 1 and 2As shown, the top cover 2 includes a positive electrode top cover 21 and a negative electrode top cover 22, which are symmetrically arranged on the left and right sides of the shell 1, and the positive electrode top cover 21 and the negative electrode top cover 22 are provided with explosion-proof valves 24, and the two explosion-proof valves 24 are connected by a connecting rod assembly 4. The connecting rod assembly 4 is arranged close to the upper part of the top cover 2 and needs to avoid the battery cell. The two explosion-proof valves 24 are symmetrically arranged on the positive electrode top cover 21 and the negative electrode top cover 22, and the two explosion-proof valves 24 are arranged close to the upper part of the top cover 2. When one explosion-proof valve 24 is opened, the other explosion-proof valve 24 will be opened at the same time under the linkage of the connecting rod assembly 4, thereby solving the problem that the existing multiple explosion-proof valves 24 cannot be opened at the same time.

[0030] As shown in Figure 2 In order to avoid reducing the energy density of the battery as much as possible, an avoidance space 31 is arranged on the top of the core package 3 for the connecting assembly to pass through, and the top elevation of the core package 3 is not lower than the top elevation of the connecting assembly.

[0031] As shown in Figure 3 The connecting rod assembly 4 includes an elastic buffer 42 and two connecting rods 41, the elastic buffer 42 is connected with the connecting rods 41 at both ends, and the other ends of the two connecting rods 41 are connected to the inner walls of the explosion-proof valves 24. The elastic buffer 42 can be a spring, and the connecting rod 41 can be a straight rod. The elastic buffer 42 is in a natural stretching state or a stretched state. The elastic buffer 42 can provide a certain deformation buffer; when the core package 3 is expanded due to heat or other factors (without thermal runaway), the distance between the two top covers 2 will increase, and if the length of the connecting rod assembly 4 cannot be adjusted, the explosion-proof valve 24 will be opened under the pulling of the connecting rod assembly 4, and the addition of the elastic buffer 42 can make adaptive stretching to avoid the misopening of the explosion-proof valve 24 due to the unadjustable length of the connecting rod assembly 4; in addition, in order to better assemble the top cover 2, it is necessary to appropriately separate the distance between the positive electrode top cover 21 and the negative electrode top cover 22, so the elastic buffer 42 can provide a certain deformation amount.

[0032] As shown in Figure 3 The top cover 2 further includes a connecting cover plate 23, the connecting cover plate 23 is fixedly connected with the upper ends of the positive electrode top cover 21 and the negative electrode top cover 22 at both ends, and the positive electrode top cover 21, the negative electrode top cover 22 and the connecting cover plate 23 are integrated in one piece as a prefabricated part. When the top cover 2 is assembled into the shell, it is assembled from top to bottom.

[0033] As shown in Figure 4As shown, the shell 1 is U-shaped in cross section, and the top surface and the left and right side surfaces of the shell 1 are provided with openings 11, and the top surface opening 11 of the shell 1 is matched with the connecting cover plate 23. The shell 1 is formed by conventional multiple stamping forming, and is changed to bending forming, thereby reducing the manufacturing cost of the shell 1, improving the production rhythm of the shell 1, and reducing the incoming material cost of the battery shell 1. The shell 1 is formed by bending forming, thereby avoiding the internal stress problem of the shell 1, solving the expansion of the shell 1, and greatly reducing the risk of welding mark failure after welding.

[0034] As shown in the drawings, Figure 4 As shown, the shell 1 is U-shaped in cross section, and the top surface and the left and right side surfaces of the shell 1 are provided with openings 11, and the top surface opening 11 of the shell 1 is matched with the connecting cover plate 23. The shell 1 is formed by conventional multiple stamping forming, and is changed to bending forming, thereby reducing the manufacturing cost of the shell 1, improving the production rhythm of the shell 1, and reducing the incoming material cost of the battery shell 1. The shell 1 is formed by bending forming, thereby avoiding the internal stress problem of the shell 1, solving the expansion of the shell 1, and greatly reducing the risk of welding mark failure after welding.

[0035] According to the description and drawings of the present application, a person skilled in the art can easily manufacture or use the anti-explosion valve double-opening power battery structure of the present application, and can produce the positive effects described in the present application.

[0036] Unless otherwise specified and limited, in the present application, if there are terms such as "length", "width", "upper", "lower", "front", "rear", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", "clockwise", "counterclockwise", "axial", "radial", "circumferential", etc. indicating the orientation or positional relationship, they are based on the orientation or positional relationship shown in the drawings, and are only for the convenience of describing the present application and simplifying the description, and therefore the terms describing the orientation or positional relationship in the present application are only used for exemplary description, and cannot be understood as limiting the present patent. For those skilled in the art, the specific meaning of the above terms can be understood in conjunction with the drawings and according to the specific circumstances.

[0037] Unless otherwise specified and limited, in the present application, if there are terms such as "setting", "connecting" and "connecting", they should be understood in a broad sense, for example, they can be fixedly connected, or can be detachably connected, or integrally connected; they can be directly connected, or indirectly connected through an intermediate medium; they can be connected inside two elements. For those skilled in the art, the specific meaning of the above terms in the present application can be understood according to the specific circumstances.

[0038] The above is only a preferred embodiment of the present application, and does not limit the present application in any form. Any simple modification or equivalent change made according to the technical essence of the present application to the above embodiment falls within the protection scope of the present application.

Claims

1. A power battery structure with a double-opening explosion-proof valve, the power battery structure comprising a housing (1), a top cover (2), and a core pack (3), characterized in that: The top cover (2) includes a positive electrode top cover (21) and a negative electrode top cover (22). The positive electrode top cover (21) and the negative electrode top cover (22) are symmetrically arranged on the left and right sides of the housing (1). An explosion-proof valve (24) is provided on both the positive electrode top cover (21) and the negative electrode top cover (22). A connecting rod assembly (4) is connected between the two explosion-proof valves (24). The linkage assembly (4) includes an elastic buffer (42) and a connecting rod (41). Both ends of the elastic buffer (42) are connected to the connecting rod (41), and the other ends of the two connecting rods (41) are respectively connected to the inner wall of the explosion-proof valve (24). The elastic buffer (42) has a deformation in the length direction of the housing (1), and the elastic buffer (42) is in a naturally extended state or a stretched state.

2. The power battery structure with double-opening explosion-proof valve according to claim 1, characterized in that: The connecting rod assembly (4) is located near the upper part of the housing (1).

3. The power battery structure with double-opening explosion-proof valve according to claim 2, characterized in that: The two explosion-proof valves (24) are symmetrically arranged on the positive electrode top cover (21) and the negative electrode top cover (22), and both explosion-proof valves (24) are located close to the upper part of the housing (1).

4. The power battery structure with double-opening explosion-proof valve according to claim 1, characterized in that: The top cover (2) also includes a connecting cover plate (23), the two ends of which are fixedly connected to the upper ends of the positive electrode top cover (21) and the negative electrode top cover (22), respectively; the shell (1) has a U-shaped cross section, and the top surface and the left and right sides of the shell (1) are all set as open openings (11), and the top opening (11) of the shell (1) matches the connecting cover plate (23).

5. The power battery structure with double-opening explosion-proof valve according to claim 4, characterized in that: A boss (12) is provided at the top opening (11) of the housing (1), and the upper surface of the boss (12) is in close contact with the lower surface of the connecting cover plate (23).

6. The power battery structure with double-opening explosion-proof valve according to claim 4, characterized in that: The shell (1) is formed by integral bending.

7. The power battery structure with double-opening explosion-proof valve according to claim 1, characterized in that: The top of the core package (3) is provided with a clearance space (31) for the connecting rod assembly (4) to pass through, and the top elevation of the core package (3) is not lower than the top elevation of the connecting rod assembly (4).

8. The power battery structure with double-opening explosion-proof valve according to claim 1, characterized in that: The top cover (2) and the shell (1) are connected by a through-welding process.

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