Battery cover explosion-proof valve protection device and battery cover

Abstract

The utility model relates to a battery cover explosion-proof valve protection device and a battery cover explosion-proof valve protection device. The battery cover explosion-proof valve protection device comprises a protection device main body and a moisture absorption ventilation block, the middle of the protection device body gradually protrudes upwards to form a closing-in plane, a plurality of ventilation windows are formed in the closing-in plane, a plurality of rib sets are arranged in the protection device body, each rib set is composed of two ribs symmetrically distributed on the two sides of the closing-in plane, and the rib sets are evenly distributed in the length direction of the closing-in plane. The periphery of the protection device main body is provided with a convex edge which horizontally protrudes outwards; the moisture absorption breathable block is fixed to the inner side of the upper closing-up plane. According to the anti-explosion valve, most of electrolyte can be prevented from directly permeating into the anti-explosion valve, meanwhile, it is guaranteed that a very small amount of electrolyte permeating from the ventilation window can be absorbed, the leaked electrolyte can be prevented from being gathered on the protection structure, and the leaked electrolyte in the liquid injection procedure is completely prevented from entering the position of the anti-explosion valve through the physical isolation and absorption effect.

Description

Technical Field

[0001] The utility model relates to the technical field of battery top covers, in particular to a battery cover explosion-proof valve protection device and a battery cover. Background Art

[0002] In the manufacturing process of lithium-ion batteries, liquid injection is an important process, which determines the amount and distribution of electrolyte inside the battery, affecting the performance and safety of the battery. In the liquid injection process, due to the low viscosity and permeability of the electrolyte, it is difficult to avoid leakage of the electrolyte. When the electrolyte penetrates into the explosion-proof valve position, the sealing performance of the explosion-proof valve will be reduced, affecting the normal operation of the explosion-proof valve, and even causing battery leakage. The explosion-proof valve is a safety protection device for the battery. When the air pressure inside the battery exceeds a certain value, the explosion-proof valve will automatically open to release gas to prevent the battery from exploding. If the sealing performance of the explosion-proof valve is reduced, the air pressure inside the battery cannot be effectively controlled, increasing the safety risks of the battery. In order to protect the explosion-proof valve from external damage and prevent the possible leakage of electrolyte from penetrating into the explosion-proof valve, an explosion-proof valve protection device is generally installed outside the explosion-proof valve.

[0003] The currently available protection devices are as follows:

[0004] The WO2023142648A1 patent applied by Contemporary Amperex Technology Co., Ltd., "Explosion-proof valve patch for batteries, end cap assemblies, batteries and electrical devices", provides an explosion-proof valve patch for sticking on the explosion-proof valve of batteries, end cap assemblies, batteries and electrical devices to seal the explosion-proof valve of the battery housing and protect the explosion-proof valve sheet. The explosion-proof patch is designed with ridges of different shapes on the plane to enhance the strength of the explosion-proof valve patch. There are air holes in the middle of the ridges of various shapes to balance the air pressure and leak detection. The technical solution of adding ridges enhances the structural strength of the protective sheet, but the accumulation of electrolyte and leakage from the air holes cannot be avoided due to the planar structure;

[0005] The CN217361832U patent applied by Shanghai Lanjun New Energy Technology Co., Ltd., "An explosion-proof valve protection patch and secondary battery", provides an explosion-proof valve protection patch, which is arranged on the top cover sheet outside the explosion-proof valve. The explosion-proof valve protection patch includes a protection patch body and a breathable layer. The breathable layer is arranged around the explosion-proof valve and is attached to the top cover sheet. There are no openings on the protection patch body, which effectively prevents the electrolyte from penetrating from the openings and corroding the explosion-proof valve. The design of the breathable layer around the periphery is difficult to ensure the penetration of the electrolyte with extremely strong permeability while ensuring that the gas can pass through, and the planar structure of the protection sheet will cause the electrolyte to accumulate;

[0006] Patent CN220291007U, "An explosion-proof pressure relief valve and battery", applied by Huizhou Yiwei Lithium Energy Co., Ltd., provides an explosion-proof valve patch, which is pasted on the battery casing to block the explosion-proof hole of the battery casing, and the explosion-proof patch can fall off from the battery casing under the action of a preset air pressure. A receiving hole is provided on the explosion-proof patch, and a breathable membrane covers the receiving hole, and the breathable membrane is arranged opposite the explosion-proof hole. The structural design of the explosion-proof pressure relief valve enables the battery to achieve a balance of air pressure inside and outside the battery through the breathable membrane under normal working conditions. When the battery has thermal runaway, the air pressure inside the battery can cause the explosion-proof patch to fall off from the battery casing, thereby achieving the effect of explosion-proof pressure relief. The technical solution of adding a breathable membrane in the receiving hole increases the structural complexity and manufacturing cost due to the introduction of a waterproof breathable membrane. Summary of the invention

[0007] The purpose of the utility model is to solve the deficiencies of the above-mentioned prior art, thereby providing a battery cover explosion-proof valve protection device, which can prevent most of the electrolyte from directly penetrating into the explosion-proof valve, while ensuring that a small amount of electrolyte penetrating from the air permeable window can be absorbed, and can also prevent the leakage of electrolyte from gathering on the protection structure, and completely prevent the electrolyte leaking in the injection process from entering the explosion-proof valve position through physical isolation and absorption.

[0008] The utility model also aims to provide a battery cover, which uses the battery cover explosion-proof valve protection device provided by the utility model.

[0009] A battery cover explosion-proof valve protection device, comprising a protection device body and a moisture-absorbing and breathable block;

[0010] The middle part of the protective device body gradually bulges upward to form a closing plane, and a plurality of ventilation windows are opened on the closing plane. There are multiple groups of rib groups inside the protective device body, and each group of the rib groups is composed of two ribs symmetrically distributed on both sides of the closing plane. The multiple groups of rib groups are evenly distributed along the length direction of the closing plane;

[0011] The outer periphery of the protective device body has a convex edge protruding horizontally outward;

[0012] The moisture-absorbing and breathable block is fixed on the inner side of the upper closing plane.

[0013] The convex edge and the closing plane are transitioned by a first curved surface and a second curved surface, wherein the first curved surface is convex outwards and the second curved surface is concave inwards.

[0014] The total area of ​​several ventilation windows shall not exceed 5% of the front projection area of ​​the entire protective device body.

[0015] The inner side surface of the rib close to the closing plane is a vertical plane, and the distance between the inner side surfaces of two ribs in the same group is slightlyThe width of the moisture-absorbing and breathable block is smaller than that of the moisture-absorbing and breathable block, and the moisture-absorbing and breathable block is fixed at a position close to the breathable window through a rib group.

[0016] The lower end of the convex edge is adhered with double-sided adhesive.

[0017] The width of the convex edge is 0.5-3 mm.

[0018] The body of the protector is made of transparent material.

[0019] The moisture-absorbent and breathable block is made of a porous material with breathable and moisture-absorbent properties.

[0020] A battery cover comprises an upper cover plate and the explosion-proof valve protection device described in the above technical solution, wherein the explosion-proof valve protection device is pasted on the explosion-proof valve of the upper cover plate.

[0021] The utility model can effectively prevent the possible leakage of electrolyte from penetrating into the explosion-proof valve and causing adverse effects under the premise of ensuring normal ventilation of the explosion-proof valve.

[0022] The utility model can prevent the vast majority of electrolytes from directly penetrating into the explosion-proof valve, and can also absorb a small amount of electrolytes penetrating from the air-permeable window, while ensuring the connection between the explosion-proof valve and the outside world.

[0023] Compared with the prior art, the beneficial effects of the utility model are:

[0024] 1. Simple structure and low cost;

[0025] 2. Provide protection for explosion-proof valves to prevent external forces from causing damage to the explosion-proof valves;

[0026] 3. Prevent electrolyte from seeping into the explosion-proof valve during injection;

[0027] 4. Prevent the leakage of electrolyte from gathering on the protective structure, causing corrosion damage to the explosion-proof valve protection structure, and at the same time the status of the explosion-proof valve can be observed. BRIEF DESCRIPTION OF THE DRAWINGS

[0028] Figure 1 It is a three-dimensional diagram of the utility model;

[0029] Figure 2 It is the front view of the utility model;

[0030] Figure 3 It is a bottom view of the utility model;

[0031] Figure 4 It is a top view of the utility model;

[0032] Figure 5 for Figure 4 BB section view;

[0033] Figure 6It is a side view of the utility model;

[0034] Figure 7 It is an exploded view of the utility model;

[0035] Figure 8 It is a partial enlarged view of the utility model;

[0036] Fig. 9 An exploded view of the battery cover and explosion-proof valve protection device;

[0037] Fig.10 A perspective view of the battery cover. DETAILED DESCRIPTION

[0038] Figure 1 to Figure 8 In the invention, the explosion-proof valve protection device is composed of the following parts: a protection device body 1, a moisture-absorbing and breathable block 6, and a double-sided adhesive tape 9; the protection device body is made of a transparent material, which can be one or a mixture of polyolefin, polyacrylic acid, nylon, polyphenylene ether ester, and cellulose resin. The shape of the front face of the protection device body (from top to bottom) is similar to the appearance of the explosion-proof valve. The middle part of the protection device body gradually bulges upward to form a closing plane 2, and the outer periphery of the bottom surface has a horizontal outward convex edge 1, and the width of the convex edge 1 is 0.5-3mm.

[0039] The side wall from the convex edge to the closing plane 2 is in a curved transition, the curved surface 1 4 protrudes outward, and when transitioning to the second curved surface, the curved surface 2 5 is concave inward. The curved surface 2 5 gradually closes, and there are a number of ventilation windows 3 on the closing plane 2. There are multiple groups of rib groups inside the protective device body, each group of the rib groups is composed of two ribs 7 symmetrically distributed on both sides of the closing plane 2, and the multiple groups of rib groups are evenly distributed along the length direction of the closing plane 2. The inner side surface 71 of the rib 7 close to the closing plane 2 is a vertical plane, and the distance between the inner side surfaces 71 of the two ribs 7 in the same group is slightly The hygroscopic and breathable block 6 is smaller than the width of the hygroscopic and breathable block 6, and the hygroscopic and breathable block 6 is fixed at a position close to the breathable window through a rib group. The hygroscopic and breathable block 6 is made of a porous material with breathability and moisture absorption, and the material can be artificial sponge, porous ceramics, activated carbon, porous fibers, water-absorbing resin, etc. The width of the hygroscopic and breathable block 6 is slightly larger than the width of the closing plane 2, and can completely cover the breathable window. A double-sided adhesive tape 9 is adhered to the lower end of the convex edge 1, and the width of the double-sided adhesive tape 9 is consistent with the width of the convex edge 1.

[0040] Figure 9~Figure 10 In the embodiment, the protective device of the utility model can be adhered to the explosion-proof valve position of the top cover by double-sided adhesive tape 9, and a seal is formed between the protective device and the top cover. The moisture-absorbing and breathable block 6 is fixed at a position close to the ventilation window by a rib group, and the protective device is fixed to the top cover by double-sided adhesive tape. After the cooperation, the explosion-proof valve of the top cover is covered by the protective device and a sealing structure is formed except for the ventilation window.

[0041] The total area of ​​all the air windows occupies ≤5% of the front projection area of ​​the entire protective device. When electrolyte splashes during liquid injection, due to the small front projection area of ​​the air windows and the design that is higher than the top cover plane, there is a very small probability that the electrolyte will pass through the air windows and enter the interior. The electrolyte splashed to the outside can quickly drip onto the top cover due to the hyperbolic shape of the outer wall of the protective device, and will not gather on the surface of the protective device, which can effectively prevent the accumulated electrolyte from corroding the protective device and causing poor appearance. The electrolyte that has a very small probability of passing through the air window and entering the interior can be absorbed by the hygroscopic breathable block to prevent it from dripping onto the explosion-proof valve and corroding the explosion-proof valve. The utility model uses a variety of technical measures to ensure that the electrolyte cannot penetrate into the explosion-proof valve, while the explosion-proof valve can be connected to the outside, so as to achieve the purpose of leak detection and air pressure balance.

Claims

1. A battery cover explosion-proof valve protection device, characterized in that: It comprises a protective device body and a moisture-absorbing and breathable block (6); The middle part of the protective device body gradually bulges upward to form a closing plane (2), and a plurality of air permeable windows (3) are provided on the closing plane (2). A plurality of rib groups are provided inside the protective device body, and each of the rib groups is composed of two ribs (7) symmetrically distributed on both sides of the closing plane (2). The plurality of rib groups are evenly distributed along the length direction of the closing plane (2); The outer periphery of the protective device body has a convex edge (1) protruding horizontally outward; The moisture-absorbing and breathable block (6) is fixed on the inner side of the upper closing plane (2).

2. A battery cover explosion-proof valve protection device according to claim 1, characterized in that: The convex edge (1) and the closing plane (2) are transitioned by a first curved surface (4) and a second curved surface (5), wherein the first curved surface (4) is convex outwards and the second curved surface (5) is concave inwards.

3. A battery cover explosion-proof valve protection device according to claim 1, characterized in that: The total area of ​​several ventilation windows shall not exceed 5% of the front projection area of ​​the entire protective device body.

4. A battery cover explosion-proof valve protection device according to claim 1, characterized in that: The inner side surface (71) of the rib (7) close to the closing plane (2) is a vertical plane, and the distance between the inner side surfaces (71) of two ribs (7) in the same group is smaller than the width of the moisture-absorbing and breathable block (6). The moisture-absorbing and breathable block (6) is fixed at a position close to the ventilation window by the rib group.

5. A battery cover explosion-proof valve protection device according to claim 1, characterized in that: The lower end of the convex edge (1) is adhered with a double-sided adhesive tape (9).

6. A battery cover explosion-proof valve protection device according to claim 1 or 5, characterized in that: The width of the convex edge (1) is 0.5-3 mm.

7. A battery cover explosion-proof valve protection device according to claim 1, characterized in that: The body of the protector is made of transparent material.

8. A battery cover explosion-proof valve protection device according to claim 1, characterized in that: The moisture-absorbent and breathable block (6) is made of a porous material having the properties of breathability and moisture absorption.

9. A battery cover, characterized in that: It comprises an upper cover plate and the explosion-proof valve protection device according to any one of claims 1 to 8, wherein the explosion-proof valve protection device is pasted on the explosion-proof valve of the upper cover plate.

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