A torsion-resistant secondary battery top cover

Abstract

This utility model provides a torsion-resistant secondary battery top cover, relating to the field of secondary battery technology. The top cover has a first surface and a second surface disposed opposite to the first surface, with the second surface facing downwards towards the plastic. The first surface of the top cover has a through-hole for mounting, and an electrode assembly is installed in the mounting hole. The first surface of the top cover and the outer side of the mounting hole have an assembly part, which consists of a connecting part and a bending part. The bending part and the connecting part are arranged vertically, respectively, which can prevent the upper plastic from moving upwards and limit the horizontal shaking of the upper plastic. After the upper plastic is formed, the positioning area and the upper plastic are interlocked, so that the circular electrode can also be prevented from torsion and loosening, ensuring the sealing of the connection.

Description

Technical Field

[0001] This utility model relates to the field of secondary battery technology, and more specifically, to a torsion-resistant secondary battery top cover. Background Technology

[0002] In recent years, with the vigorous development of new energy, various companies have flocked to the new energy sector. Intense competition has led to increasingly higher cost requirements, making the pursuit of an extremely simplified top cover a pressing need for major battery manufacturers. Lithium batteries are mainly divided into prismatic batteries and pouch batteries. In prismatic batteries, the top cover is a crucial structure that serves a sealing function. The terminals assembled within the top cover are the core components that enable electrical connections between individual cells within the battery pack. The physical characteristics of the terminals directly affect the performance of the battery system. Regarding connection processes, different types of terminals, such as externally threaded terminals and internally threaded terminals, correspond to different connection methods such as laser welding and bolt tightening. This choice directly affects the contact resistance and vibration resistance of the battery pack.

[0003] After the prismatic battery is filled with electrolyte, the sealing between the terminal and the top cover is crucial to prevent leakage. The current sealing method is the combination of a sealing ring and an upper plastic to fill the gap between the terminal and the top cover. To ensure the sealing, the sealing ring and the upper plastic must not be moved or rotated. However, the sealing ring and the upper plastic in the existing round terminal are at risk of loosening, and the connection cannot be guaranteed. Utility Model Content

[0004] The technical problem to be solved by this utility model is that the sealing ring and the upper plastic in the existing circular pole are at risk of loosening, and the connection cannot be guaranteed. In view of the problems existing in the prior art, an anti-torsion type secondary battery top cover is provided.

[0005] The purpose and effects of this utility model are achieved by the following specific technical means:

[0006] An anti-torsion type secondary battery top cover includes a top cover and a lower plastic assembly fitted to the bottom of the top cover;

[0007] The top cover has a first surface and a second surface disposed opposite to the first surface, the second surface facing downward plastic, and the first surface of the top cover has a mounting hole that passes through the top cover, and an electrode assembly is installed in the mounting hole;

[0008] The top cover has an assembly part on its first surface and outside the mounting hole. The assembly part consists of a connecting part and a bending part. The bending part and the connecting part are arranged vertically. The connecting part has several positioning areas. The top of the assembly part is a bending part, which is fixed to the top of the pole assembly.

[0009] With this design, the pole assembly is first installed in the mounting hole, and then the top of the assembly part is bent and locked to the top of the pole assembly, ensuring the installability of the pole assembly.

[0010] A further preferred embodiment: the electrode assembly includes an electrode, an upper plastic part, and a sealing ring. The electrode passes through the mounting hole and the lower plastic part. The sealing ring is disposed between the electrode and the mounting hole at the mounting position. The upper plastic part is disposed between the assembly part and the electrode.

[0011] A further preferred embodiment: the first surface of the top cover, located between the outside of the mounting hole and the inside of the assembly part, is a stepped portion, and the upper plastic covers the stepped portion, thereby positioning the upper plastic between the mounting hole and the assembly part.

[0012] A further preferred embodiment: the wall thickness of the connecting part is greater than the wall thickness of the bending part, and a wall thickness reduction zone is provided between the bending part and the connecting part. This design makes the assembly part easier to bend.

[0013] A further preferred embodiment: the number of positioning areas is one or more, the positioning areas are concave or convex, and the positioning areas are connected to the upper plastic. The positioning areas can prevent the upper plastic from rotating and restrict its movement.

[0014] A further preferred embodiment: when the positioning area is concave, the concave depth is 0.1mm-2mm.

[0015] A further preferred embodiment: the assembly part is bent inward with the thickness reduction zone as the boundary to form a bent part, and the upper plastic part is connected to the bent part to form an embedded part.

[0016] A further preferred embodiment: the assembly part is cylindrical or has several gaps. When the assembly part is cylindrical with gaps, the number of gaps is 2-5.

[0017] A further preferred embodiment: the first surface of the top cover has an explosion-proof hole and a liquid injection hole between the mounting holes, and the explosion-proof hole and the liquid injection hole penetrate through the top cover.

[0018] The beneficial effects of this utility model are:

[0019] 1. Bend the bending part at 90°, and arrange the bending part and the connecting part in an L-shape. Finally, inject the upper plastic into the space between the connecting part and the pole through one-piece injection molding. The upper plastic presses the pole and the sealing ring together. The bending part abuts against the top of the upper plastic, thereby restricting the upward displacement of the entire pole assembly. The step part can restrict the downward movement of the upper plastic. The connection position between the upper plastic and the bending part forms an embedded part. The embedded part of the upper plastic can improve the tightness. Moreover, the embedded part of the upper plastic forms a right angle and contacts the two sides of the bending part, with a larger contact area. This not only prevents the upper plastic from moving upward, but also restricts the horizontal shaking of the upper plastic, ensuring the sealing of the pole connection.

[0020] After the upper plastic is formed, the positioning area and the upper plastic are interlocked to further restrict the rotation of the upper plastic. This design also prevents the circular pole from twisting and loosening, ensuring the sealing of the connection. Attached Figure Description

[0021] The present invention will be further described below with reference to the accompanying drawings.

[0022] Figure 1 This is an exploded view of the overall structure of this utility model;

[0023] Figure 2 This is a schematic diagram of the top cover structure of this utility model;

[0024] Figure 3 This utility model Figure 2 A schematic diagram of a local structure in the image;

[0025] Figure 4 This utility model Figure 2 A schematic diagram of a local structure in the image;

[0026] Figure 5 This utility model Figure 2 The main view;

[0027] Figure 6 This is a partial front view of the top cover structure of this utility model.

[0028] Figures 1-6 Middle: Top cover (1), mounting hole (101), assembly part (2), connecting part (201), positioning area (202), bending part (3), pole post assembly (4), lower plastic (5). Detailed Implementation

[0029] To better understand the above-mentioned objectives, features, and advantages of this utility model, the present utility model will be further described in detail below with reference to the accompanying drawings and specific embodiments. The following embodiments are merely examples for implementing this utility model. It must be pointed out that the disclosed embodiments do not limit the scope of this utility model. On the contrary, any modifications and refinements made without departing from the scope of this utility model are within the patent protection scope of this utility model.

[0030] Please see Figure 1 and Figure 6 An anti-torsion secondary battery top cover includes a top cover and a lower plastic assembly fitted to the bottom of the top cover. The top cover has a first surface and a second surface disposed opposite to the first surface, with the second surface facing the lower plastic assembly. The first surface of the top cover has two mounting holes that pass through the top cover: a positive terminal hole and a negative terminal hole. A positive terminal assembly and a negative terminal assembly are respectively installed in the mounting holes. Each terminal assembly includes a terminal, an upper plastic assembly, and a sealing ring. The positive terminal is made of aluminum, and the negative terminal is made of copper-aluminum composite. The terminal passes through the mounting hole and the lower plastic assembly. The terminal can be welded to a metal connecting piece later. The metal connecting piece is the electrical transmission structure between the terminal and the bare battery cell. The sealing ring is compressed between the terminal and the mounting hole at the mounting position, and the sealing ring can seal the connection gap between the terminal and the mounting hole.

[0031] Please see Figures 1-6 The top cover has an assembly part on its first surface, located outside the mounting hole. This assembly part can be integrally formed with the top cover or welded separately. The assembly part consists of a connecting part and a bending part, arranged vertically above and below each other. Figure 3 and Figure 4 The assembly part is cylindrical or has several gaps. When the assembly part is cylindrical with gaps, the gaps are preferably 2-5, and when there are 2 gaps, the two gaps are preferably arranged horizontally and symmetrically. The assembly part does not obstruct the mounting hole in its initial state. When assembling the pole assembly, first, the sealing ring is put into the pole, then the pole with the sealing ring is assembled into the mounting hole. Then, the bent part is bent at 90° by riveting or pressing. The bent part and the connecting part are arranged in an L-shape. Finally, the upper plastic is injected into the space between the connecting part and the pole by integral injection molding. Figure 6 The upper plastic presses the pole and the sealing ring together, and the bent part presses against the top of the upper plastic, thereby restricting the upward displacement of the entire pole assembly;

[0032] Preferred, such as Figure 6 As shown, the first surface of the top cover, located between the outside of the mounting hole and the inside of the assembly part, is a stepped part. The upper plastic covers the stepped part, and the step part can restrict the downward movement of the upper plastic.

[0033] Preferred, such as Figure 6As shown, the upper plastic and the bending part are connected to form an embedded part. The embedded part of the upper plastic can improve the tightness. The embedded part of the upper plastic forms a right angle and contacts the two sides of the bending part, resulting in a larger contact area. This not only prevents the upper plastic from moving upward, but also limits the horizontal shaking of the upper plastic, ensuring the sealing of the pole connection.

[0034] Please see Figures 3-6 The wall thickness of the connecting part is greater than that of the bending part, and a wall thickness reduction zone is provided between the bending part and the connecting part, such as... Figure 3 The top of the inner wall of the connecting part gradually thins out at an angle to form a wall thickness reduction zone. When bending, the bending part is formed by bending inward with the thickness reduction zone as the boundary. The wall thickness of the thickness reduction zone is thinner, making it easier to fold and process. Taking the riveting process as an example, because the assembly part is round, the riveting end of the processing equipment moves down while rotating to bend the assembly part. The processing can be completed in 3-4 seconds. The processing speed is fast, and the processing efficiency of circles is higher than that of ellipses and polygons.

[0035] Furthermore, such as Figure 3 and 4 The connecting part is provided with several positioning areas, one or more of which are concave or convex. After the upper plastic is injected into the assembly part and the pole, it will connect with the upper plastic. After the upper plastic is formed, the positioning area and the upper plastic are interlocked to further restrict the rotation of the upper plastic. Through this design, the circular pole can also be prevented from twisting and loosening, ensuring the sealing of the connection.

[0036] Please see Figure 1 An explosion-proof hole and a liquid injection hole are provided on the first surface of the top cover between the mounting holes. The explosion-proof hole and the liquid injection hole pass through the top cover. An explosion-proof valve is installed in the explosion-proof hole for explosion-proof pressure relief. Electrolyte can be injected into the shell through the liquid injection hole.

Claims

1. A torsion-resistant secondary battery top cover, comprising a top cover and a lower plastic assembly fitted to the bottom of the top cover, characterized in that: The top cover has a first surface and a second surface disposed opposite to the first surface, the second surface facing downward plastic, and the first surface of the top cover has a mounting hole that passes through the top cover, and an electrode assembly is installed in the mounting hole; The first surface of the top cover is provided with an assembly part located outside the mounting hole. The assembly part consists of a connecting part and a bending part. The bending part and the connecting part are arranged vertically. The connecting part is provided with several positioning areas. The top of the assembly part is a bending part, which is fixed to the top of the pole assembly.

2. The anti-torque type secondary battery top cover according to claim 1, characterized in that: The electrode assembly includes an electrode, an upper plastic part, and a sealing ring. The electrode passes through a mounting hole and a lower plastic part. The sealing ring is disposed between the electrode and the mounting hole at the mounting position. The upper plastic part is disposed between the assembly part and the electrode.

3. The anti-torque type secondary battery top cover according to claim 2, characterized in that: The first surface of the top cover, located between the mounting hole and the assembly part, is a stepped portion, and the upper plastic covers the stepped portion.

4. The anti-torque type secondary battery top cover according to claim 2, characterized in that: The wall thickness of the connecting part is greater than that of the bending part, and a wall thickness reduction zone is provided between the bending part and the connecting part.

5. The anti-torque type secondary battery top cover according to claim 2, characterized in that: The number of positioning areas is one or more, and the positioning areas are concave or convex, and the positioning areas are connected to the upper plastic.

6. The anti-torque type secondary battery top cover according to claim 5, characterized in that: When the positioning area is concave, the concave depth is 0.1mm-2mm.

7. The anti-torque type secondary battery top cover according to claim 4, characterized in that: The assembly part bends inward from the thickness reduction zone to form a bent part, and the upper plastic part connects with the bent part to form an embedded part.

8. The anti-torque type secondary battery top cover according to claim 1, characterized in that: The assembly part is cylindrical or has several gaps. When the assembly part is cylindrical with gaps, the number of gaps is 2-5.

9. The anti-torque type secondary battery top cover according to claim 1, characterized in that: The top cover has an explosion-proof hole and a liquid injection hole on its first surface between the mounting holes, and the explosion-proof hole and the liquid injection hole penetrate through the top cover.

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