CN220435526U - Explosion-proof valve, cover plate and battery - Google Patents

Abstract

The utility model discloses an explosion-proof valve, a cover plate and a battery, and relates to the technical field of batteries. The explosion-proof valve comprises a valve body, an explosion-proof piece and a locking ring, wherein the valve body is provided with a through hole, and the through hole comprises a large-diameter section and a small-diameter section which are communicated with each other; the explosion-proof piece is arranged in the through hole and is positioned on a step formed by the large-diameter section and the small-diameter section, and a first sealing ring is arranged between the explosion-proof piece and the step; the locking ring is arranged in the through hole and detachably connected with the large-diameter section, and the locking ring is configured to lock the explosion-proof sheet on the step. The explosion-proof valve can replace the explosion-proof piece, thereby greatly reducing the cost.

Description

Explosion-proof valve, cover plate and battery

Technical Field

The utility model relates to the technical field of batteries, in particular to an explosion-proof valve, a cover plate and a battery.

Background

The lithium battery has the advantages of large capacity, light weight, long cycle life, high energy density, no memory, environmental friendliness and the like, and has wide application in the fields of electric automobiles, electric tools, household appliances, military industry, aerospace and the like, and the demand of the current market for the lithium battery with large capacity and high multiplying power is more and more urgent.

The explosion-proof valve needs to ensure sealing performance, so the explosion-proof valve and the cover plate are welded together in a laser welding mode, the cover plate and the explosion-proof valve form a whole, and after a large amount of gas is generated in the lithium battery to break the explosion-proof plate, the whole cover plate needs to be replaced, so that the cost is high.

Aiming at the problems, an explosion-proof valve, a cover plate and a battery need to be developed to solve the problem that the cost is high because the whole cover plate needs to be replaced after an explosion-proof piece is broken.

Disclosure of Invention

The utility model aims to provide an explosion-proof valve, a cover plate and a battery, which can replace an explosion-proof piece, thereby greatly reducing the cost.

To achieve the purpose, the utility model adopts the following technical scheme:

an explosion protection valve comprising:

the valve comprises a valve body, wherein the valve body is provided with a through hole, and the through hole comprises a large-diameter section and a small-diameter section which are communicated with each other;

the explosion-proof piece is arranged in the through hole and is positioned on a step formed by the large-diameter section and the small-diameter section, and a first sealing ring is arranged between the explosion-proof piece and the step;

the locking ring is arranged in the through hole and detachably connected with the large-diameter section, and the locking ring is configured to lock the explosion-proof sheet on the step.

In some embodiments, the locking ring is threadably coupled to the inner side of the large diameter section.

In some embodiments, at least one side of the rupture disc is provided with a thinned groove.

In some embodiments, the thinned groove is a C-shaped groove.

In some embodiments, an end face of the locking ring facing away from the rupture disc is lower than a surface of the valve body.

In some embodiments, a plurality of screwing grooves are formed in the end, facing away from the explosion-proof sheet, of the locking ring along the circumferential direction.

The cover plate comprises a cover plate body and an explosion-proof valve, wherein the cover plate body is provided with an explosion-proof hole, and the explosion-proof valve is arranged in the explosion-proof hole.

In some embodiments, the valve body comprises a cylinder portion and a pressing edge formed by extending outwards along the periphery of the cylinder portion, the cover plate body is convexly provided with a reinforcing table along the periphery of the explosion-proof hole, the cylinder portion is arranged in the explosion-proof hole, and the pressing edge is abutted to the reinforcing table.

In some embodiments, the cover plate further comprises a second seal ring located between the pressing edge and the reinforcing table.

A battery comprises a shell and a cover plate, wherein the shell is provided with an opening, and the cover plate is fixedly connected with the shell and seals the opening.

The utility model has the beneficial effects that:

the utility model provides an explosion-proof valve, a cover plate and a battery. In the explosion-proof valve, the through hole formed in the valve body is used for being communicated to the inside of a battery, the explosion-proof piece is locked on the step by the locking ring, and the locking ring is detachably connected with the large-diameter section, so that when the explosion-proof piece needs to be replaced, the locking ring can be detached, and after the explosion-proof piece is replaced, the locking ring is utilized to lock a new explosion-proof piece on the step. And the first sealing ring between the explosion-proof piece and the step can ensure the tightness of the explosion-proof valve and avoid the leakage of the battery.

The explosion-proof valve can only replace the explosion-proof piece, thereby greatly reducing the cost.

Drawings

FIG. 1 is a cross-sectional view of a cover plate provided by the present utility model;

FIG. 2 is a top view of the rupture disc provided by the present utility model;

fig. 3 is a top view of a locking ring provided by the present utility model.

In the figure:

1. a cover plate body; 2. an explosion-proof valve; 3. a second seal ring;

11. a reinforcement stand; 21. a valve body; 22. explosion-proof sheet; 23. a locking ring; 24. a first seal ring;

211. a through hole; 212. a large diameter section; 213. a small diameter section; 214. a cylinder portion; 215. a pressing edge; 221. thinning the groove; 231. the groove is screwed.

Detailed Description

Embodiments of the present utility model are described in detail below, examples of which are illustrated in the accompanying drawings, wherein like or similar reference numerals refer to like or similar elements or elements having like or similar functions throughout. The embodiments described below by referring to the drawings are illustrative and intended to explain the present utility model and should not be construed as limiting the utility model.

In the description of the present utility model, it should be noted that the directions or positional relationships indicated by the terms "center", "upper", "lower", "left", "right", "vertical", "horizontal", "inner", "outer", etc. are based on the directions or positional relationships shown in the drawings, are merely for convenience of describing the present utility model and simplifying the description, and do not indicate or imply that the devices or elements referred to must have a specific orientation, be configured and operated in a specific orientation, and thus should not be construed as limiting the present utility model. Furthermore, the terms "first," "second," and the like, are used for descriptive purposes only and are not to be construed as indicating or implying relative importance. Wherein the terms "first position" and "second position" are two different positions.

Unless specifically stated or limited otherwise, the terms "mounted," "connected," and "fixed" are to be construed broadly, and may be, for example, either fixed or removable; can be mechanically or electrically connected; can be directly connected or indirectly connected through an intermediate medium, and can be communicated with the inside of two elements or the interaction relationship of the two elements. The specific meaning of the above terms in the present utility model can be understood by those of ordinary skill in the art according to the specific circumstances.

Unless expressly stated or limited otherwise, a first feature being "above" or "below" a second feature may include the first feature and the second feature being in direct contact, or may include the first feature and the second feature not being in direct contact but being in contact with each other by way of additional features therebetween. Moreover, a first feature being "above," "over" and "on" a second feature includes the first feature being directly above and obliquely above the second feature, or simply indicating that the first feature is higher in level than the second feature. The first feature being "under", "below" and "beneath" the second feature includes the first feature being directly under and obliquely below the second feature, or simply means that the first feature is less level than the second feature.

The technical scheme of the utility model is further described below by the specific embodiments with reference to the accompanying drawings.

The embodiment provides a battery, which comprises a shell, a cover plate, a positive plate, a negative plate, a diaphragm, electrolyte and the like, wherein the positive plate, the negative plate, the diaphragm, the electrolyte and the like are arranged in the shell. The shell is provided with an opening, the positive plate, the negative plate and the diaphragm are arranged in the shell through the opening, the cover plate is fixedly connected with the shell and seals the opening, then electrolyte is injected into the shell through the electrolyte injection hole of the cover plate, and finally the electrolyte injection hole is sealed.

In this embodiment, a lithium battery will be described as an example. The lithium battery has the advantages of large capacity, light weight, long cycle life, high energy density, no memory, environmental friendliness and the like, and has wide application in the fields of electric automobiles, electric tools, household appliances, military industry, aerospace and the like, and the demand of the current market for the lithium battery with large capacity and high multiplying power is more and more urgent.

However, the high energy density means that a large amount of high temperature gas is released when the battery cells are thermally out of control, and in order to prevent explosion of the battery, the released large amount of gas needs to be discharged out of the housing. As shown in fig. 1, in the present embodiment, the cover plate includes a cover plate body 1 and an explosion-proof valve 2, the cover plate body 1 is provided with an explosion-proof hole, and the explosion-proof valve 2 is disposed in the explosion-proof hole. When the battery core releases a large amount of gas, the air pressure in the shell rises along with the release of the battery core, and when the air pressure rises to exceed the threshold value of the explosion-proof valve 2, the explosion-proof valve 2 is broken, so that the pressure relief effect is realized.

Further, the explosion-proof valve 2 includes a valve body 21, the valve body 21 includes a tube portion 214 and a pressing edge 215 extending outward along the outer circumference of the tube portion 214, the cover plate body 1 is provided with a reinforcing table 11 protruding along the circumference of the explosion-proof hole, the tube portion 214 is disposed in the explosion-proof hole, and the pressing edge 215 abuts against the reinforcing table 11. The tube portion 214 is located in the explosion-proof hole so that the valve body 21 is connected with the cover plate body 1, and the pressing edge 215 abuts against the reinforcing table 11 to play a limiting role between the valve body 21 and the cover plate body 1, so that stability between the valve body 21 and the cover plate body 1 is improved.

The cylindrical portion 214 is in threaded connection with the cover plate body 1, so that the valve body 21 and the cover plate body 1 can be conveniently assembled and disassembled. When the valve body 21 is screwed into the explosion-proof hole until the pressing edge 215 abuts against the reinforcing table 11, the valve body 21 and the cover plate body 1 are assembled in place.

It is worth noting that the reinforcing table 11 of the cover plate body 1 can increase the axial thickness of the explosion-proof hole, not only can increase the length of the threaded connection between the explosion-proof valve 2 and the explosion-proof hole, but also can increase the strength near the explosion-proof hole, and when the high-temperature gas released by the thermal runaway of the battery cell impacts the explosion-proof valve 2, the cover plate body 1 cannot deform or be damaged.

As shown in fig. 1, the cover plate further includes a second sealing ring 3, and the second sealing ring 3 is located between the pressing edge 215 and the reinforcing table 11. Since the explosion-proof valve 2 is installed in the explosion-proof hole and is not integrally formed, the tightness between the explosion-proof valve 2 and the cover plate body 1 is improved by the second sealing ring 3, and the electrolyte in the shell is prevented from leaking through the gap between the explosion-proof valve 2 and the cover plate body 1. The pressing edge 215 and the reinforcing table 11 can enable the extrusion force of the explosion-proof valve 2 and the cover plate body 1 to the second sealing ring 3 to be applied along the axial direction, so that the extrusion force received by the second sealing ring 3 is gradually increased along with the screwing of the cylinder part into the explosion-proof hole, and the sealing effect is good.

It can be understood that the second sealing ring 3 is sleeved on the periphery of the cylindrical portion 214 and is arranged at intervals with the cylindrical portion 214, so that the direction of the extrusion force of the explosion-proof valve 2 and the cover plate body 1 to the second sealing ring 3 is the same as the axial direction of the explosion-proof hole, and the deformation direction and the deformation amount of the second sealing ring 3 are controllable, so that the preset sealing effect is achieved.

To achieve the above object, at least one of the reinforcing table 11 and the pressing edge 215 is provided with a first annular groove, and the second seal ring 3 is positioned in the first annular groove, so that the size of the gap between the second seal ring 3 and the cylindrical portion 214 is kept stable.

Due to the arrangement of the pressing edge 215, the axial section of the explosion-proof valve 2 is T-shaped with a hole in the middle.

It will be appreciated that the sealing performance of the explosion-proof valve 2 needs to be ensured, so the explosion-proof valve 2 and the cover plate are welded together in a laser welding manner, so that the cover plate and the explosion-proof valve 2 form a whole, and when a large amount of gas is generated in the lithium battery to break the explosion-proof sheet 22, the whole cover plate needs to be replaced, so that the cost is high.

As shown in fig. 1 to 3, in the present embodiment, the explosion-proof valve 2 further includes an explosion-proof sheet 22 and a locking ring 23, the valve body 21 is provided with a through hole 211, the through hole 211 includes a large diameter section 212 and a small diameter section 213 which are communicated, the explosion-proof sheet 22 is disposed in the through hole 211 and is located on a step formed by the large diameter section 212 and the small diameter section 213, the locking ring 23 is disposed in the through hole 211 and is detachably connected with the large diameter section 212, and the locking ring 23 is configured to lock the explosion-proof sheet 22 on the step.

In the explosion-proof valve 2, the through hole 211 formed in the valve body 21 is used for being communicated to the inside of a battery, the explosion-proof sheet 22 is locked on a step by the locking ring 23, and the locking ring 23 is detachably connected with the large-diameter section 212, so that when the explosion-proof sheet 22 needs to be replaced, the locking ring 23 can be detached, and after the explosion-proof sheet 22 is replaced, a new explosion-proof sheet 22 is locked on the step by using the locking ring 23, thereby greatly reducing the cost of replacing the explosion-proof sheet 22.

Preferably, the valve body 21 further comprises a first sealing ring 24, the first sealing ring 24 being arranged between the rupture disc 22 and the step. The first sealing ring 24 between the explosion-proof piece 22 and the step can ensure the tightness of the explosion-proof valve 2 and avoid battery leakage. Moreover, the position of the first sealing ring 24 is closest to the small diameter section 213, that is, when the high temperature gas flows to the small diameter section 213, the first sealing ring 24 can play a role in sealing, so that the explosion-proof valve 2 cannot leak gas when the explosion-proof sheet 22 is not broken.

Preferably, the locking ring 23 is in threaded connection with the inner side surface of the large-diameter section 212, so that the locking ring 23 is convenient to disassemble and assemble, and the locking ring 23 can be prevented from being jacked up by the explosion-proof sheet 22 when the explosion-proof sheet is subjected to small pressure, so that the reliability of the explosion-proof valve 2 is improved.

Wherein the inner diameter of the small diameter section 213 is 70% -85% of the inner diameter of the large diameter section 212. The difference between the inner diameter of the small diameter section 213 and the inner diameter of the large diameter section 212 cannot be too small, which would result in a smaller step width and an inability to stably place the first seal ring 24; the difference between the inner diameter of the small diameter section 213 and the inner diameter of the large diameter section 212 cannot be too large, if the difference is too large, the diameter of the small diameter section 213 is relatively small, and when the battery core is in thermal runaway, the pressure applied to the explosion-proof sheet 22 is small, so that the explosion-proof sheet cannot be broken, and the potential safety hazard of explosion exists. Specifically, the inner diameter of small diameter section 213 is 80% of the inner diameter of large diameter section 212.

As shown in fig. 1 and 2, at least one side of the rupture disc 22 is provided with a thinning groove 221. The thinning grooves 221 can reduce the local strength of the rupture disc 22, so that when the rupture disc 22 bears the gas pressure in the casing, the rupture disc 22 is ruptured at the position where the thinning grooves 221 are arranged preferentially, and the rupture state when the rupture disc 22 is ruptured is ensured to be consistent with the preset rupture state.

As shown in fig. 2, the thinning groove 221 is a C-shaped groove, that is, the thinning groove 221 is annular and is not connected end to end. When blasting occurs, the pressure is released by the internal pressure directly bursting the C-shaped groove due to the weaker notched part, and the part between the head and the tail of the C-shaped groove is not burst due to the pressure released by the C-shaped groove, so that the internal harmful substances can be prevented from splashing, and the explosion-proof piece 22 can be prevented from being burst into a plurality of parts to scatter around.

Wherein, the length of the C-shaped groove accounts for 70% -90% of the circumference of the C-shaped groove, the ratio of the C-shaped groove to the circumference of the C-shaped groove is too low, which causes the bursting area of the anti-explosion sheet 22 to be too small, but increases the release speed of the high temperature gas, the ratio of the C-shaped groove to the circumference of the C-shaped groove is too high, which causes the part between the head and the tail of the C-shaped groove to be too short, the strength of the C-shaped groove to be too low, and the part in the C-shaped groove is easy to be directly broken and scattered around when the anti-explosion sheet 22 is burst.

In this embodiment, the length of the C-shaped groove is 80% of the circumferential length of the groove, and the ungrooved portion is 20% of the circumferential length of the groove.

In other embodiments, the thinned groove 221 may also be other shapes, such as a cross shape. When the thermal runaway of the battery cell occurs, the cross-shaped thinning groove 221 breaks from the middle and extends along the cross-shaped periphery, so that the pressure relief effect is realized, the broken part cannot be broken thoroughly, and the explosion-proof piece 22 is prevented from being broken into a plurality of parts to scatter around.

Preferably, the end face of the locking ring 23 facing away from the rupture disc 22 is lower than the surface of the valve body 21. That is, the locking ring 23 is completely located within the large diameter section 212 without protruding the valve body 21, thereby preventing the locking ring 23 from interfering with other structures of the battery pack to cause safety accidents.

As shown in fig. 1 and 3, a plurality of screwing grooves 231 are formed in the circumferential direction at one end of the locking ring 23 facing away from the explosion proof plate 22. Since the locking ring 23 is completely immersed into the large diameter section 212, it is inconvenient to mount or dismount the locking ring 23, and it is difficult for an operator to drive the locking ring 23 to rotate. The locking ring 23 is provided with a plurality of screw grooves 231, into which a tool such as a screwdriver or other pointed object can be inserted, and then the locking ring 23 is driven to rotate by the screw grooves 231.

Preferably, the plurality of screwing grooves 231 are provided at equal intervals so that the force of the locking ring 23 is more balanced by inserting the plurality of tools into the symmetrical screwing grooves 231, thereby facilitating the rotation of the locking ring 23. In the present embodiment, the locking ring 23 is provided with two screw grooves 231 in total, and is located at both ends of the locking ring 23 in the radial direction.

The foregoing is merely exemplary of the present utility model, and those skilled in the art should not be considered as limiting the utility model, since modifications may be made in the specific embodiments and application scope of the utility model in light of the teachings of the present utility model.

Claims (10)

1. An explosion-proof valve, comprising:

the valve comprises a valve body (21), wherein the valve body (21) is provided with a through hole (211), and the through hole (211) comprises a large-diameter section (212) and a small-diameter section (213) which are communicated with each other;

the explosion-proof piece (22) is arranged in the through hole (211) and is positioned on a step formed by the large-diameter section (212) and the small-diameter section (213), and a first sealing ring (24) is arranged between the explosion-proof piece (22) and the step;

-a locking ring (23), said locking ring (23) being arranged in said through hole (211) and being removably connected to said large diameter section (212), said locking ring (23) being configured to lock said rupture disc (22) onto said step.

2. The explosion-proof valve according to claim 1, wherein the locking ring (23) is screwed with the inner side of the large diameter section (212).

3. Explosion-proof valve according to claim 1, characterized in that at least one side of the explosion-proof disc (22) is provided with a thinning groove (221).

4. An explosion-proof valve according to claim 3, characterized in that the thinning groove (221) is a C-shaped groove.

5. An explosion-proof valve according to claim 1, characterized in that the end face of the locking ring (23) facing away from the explosion-proof disc (22) is lower than the surface of the valve body (21).

6. The explosion-proof valve according to claim 1, characterized in that the end of the locking ring (23) facing away from the explosion-proof plate (22) is provided with a plurality of screwing grooves (231) in the circumferential direction.

7. A cover plate, characterized by comprising a cover plate body (1) and the explosion-proof valve (2) according to any one of claims 1-6, wherein the cover plate body (1) is provided with explosion-proof holes, and the explosion-proof valve (2) is arranged in the explosion-proof holes.

8. The cover plate according to claim 7, wherein the valve body (21) comprises a cylindrical portion (214) and a pressing edge (215) formed by extending outwards along the periphery of the cylindrical portion (214), the cover plate body (1) is convexly provided with a reinforcing table (11) along the circumference of the explosion-proof hole, the cylindrical portion (214) is arranged in the explosion-proof hole, and the pressing edge (215) is abutted against the reinforcing table (11).

9. The cover plate according to claim 8, further comprising a second sealing ring (3), the second sealing ring (3) being located between the pressing edge (215) and the reinforcement table (11).

10. A battery comprising a housing provided with an opening and a cover plate according to any one of claims 7 to 9, the cover plate being fixedly connected to the housing and closing the opening.