A pressure relief assembly, cover plate, battery, and battery pack

Abstract

The utility model provides a kind of pressure relief assembly, cover plate, battery and battery pack, belong to battery technical field, pressure relief assembly includes valve body and the elastic sealing component of being sleeved on the outer circumferential surface of valve body, valve body is equipped with the air hole of intercommunication sealed cavity, elastic sealing component seals air hole, when the pressure of sealed cavity exceeds the pre-tightening force of elastic sealing component, elastic sealing component and valve body part separate to form the pressure relief passage of intercommunication sealed cavity and external environment;Otherwise elastic sealing component and valve body contact and seal air hole to close pressure relief passage.Affirmative effect: pressure relief assembly can control pressure relief process according to the pressure change of sealed cavity, realize the pressure relief of sealed cavity, prevent excessive accumulation of pressure, while ensure the sealing property of sealed cavity;In battery application has the cover plate of this pressure relief assembly, can realize the pressure relief of electric core inside, avoid the problem of cover plate bulging deformation due to high internal pressure in electric core, to solve the assembly problem and leakage risk etc. problem caused by cover plate deformation.

Description

Technical Field

[0001] This utility model relates to the field of battery technology, and in particular to a pressure relief component, a cover plate, a battery, and a battery pack. Background Technology

[0002] With the rapid development of electric vehicles, the safety performance of batteries, as a core component, is receiving increasing attention. During the use of battery cells, the electrode materials and electrolyte inside the cells continuously react, generating a large amount of gas. Since a battery cell is typically a relatively enclosed space, the gas generated inside cannot escape in time and accumulates continuously. As the amount of gas increases, the internal pressure of the cell gradually increases. When the internal pressure rises but does not reach the opening pressure of the explosion-proof valve, the cover may bulge and deform, thus affecting the assembly of the battery cells.

[0003] Furthermore, explosion-proof valves on battery covers are typically designed with grooves to release pressure by tearing through these grooves when the internal pressure of the battery cell becomes too high, thus ensuring the cell's safety. However, if the deformation of the cover is excessive, the grooves on the explosion-proof valve may tear prematurely, leading to a risk of electrolyte leakage inside the battery cell. This could damage surrounding equipment and the environment, and even cause a safety accident, seriously threatening the personal safety of users. Utility Model Content

[0004] To solve the above technical problems, this utility model provides a pressure relief component; on the other hand, it also provides a cover plate; furthermore, it provides a battery; and still moreover, it provides a battery pack.

[0005] The technical problem solved by this utility model can be achieved by the following technical solution:

[0006] On the one hand, a pressure relief assembly is provided for relieving pressure in a sealed cavity, comprising:

[0007] A valve body, wherein the valve body is provided with an air hole communicating with the sealing cavity;

[0008] An elastic sealing component is sleeved on the outer peripheral surface of the valve body and seals the air hole. When the pressure in the sealing cavity exceeds the preload of the elastic sealing component, the elastic sealing component partially separates from the valve body to form a pressure relief channel connecting the sealing cavity with the external environment. When the pressure in the sealing cavity does not exceed the preload of the elastic sealing component, the elastic sealing component contacts the valve body and seals the air hole to close the pressure relief channel.

[0009] Preferably, the vents are arranged at an angle.

[0010] Preferably, the outer peripheral surface of the valve body is provided with a flange, and part of the elastic sealing component is sleeved on the flange;

[0011] The vent is tilted away from the flange.

[0012] On the other hand, a cover plate is also provided for covering a housing having a receiving cavity to form a sealed cavity, the cover plate including a cover plate body having a through hole, and the through hole having a pressure relief component as described above.

[0013] Preferably, the cover plate body is provided with a cover plate explosion-proof valve, and the pre-tightening force of the pressure relief component is lower than the opening value of the cover plate explosion-proof valve.

[0014] Preferably, the cover plate body has an explosion-proof groove area, and explosion-proof grooves are formed in the explosion-proof groove area.

[0015] Preferably, the cover plate body is further provided with a stress shielding plate, which is disposed in the explosion-proof groove area and located at a position where no explosion-proof groove is made.

[0016] Preferably, the stress shielding plate is attached to the explosion-proof groove area using structural adhesive.

[0017] In another aspect, a battery is also provided, the battery comprising a housing having a receiving cavity, characterized in that the housing is covered with a cover plate as described above.

[0018] In another aspect, a battery pack is also provided, characterized in that the battery pack includes the batteries as described above.

[0019] The advantages or beneficial effects of this utility model's technical solution are as follows:

[0020] This utility model's pressure relief assembly, through the use of a valve body and an elastic sealing component sleeved on the outer circumference of the valve body, can control the pressure relief process according to the pressure changes in the sealing cavity. When the pressure in the sealing cavity exceeds the pre-tightening force of the elastic sealing component, the elastic sealing component partially separates from the valve body to form a pressure relief channel connecting the sealing cavity with the external environment, thereby achieving pressure relief in the sealing cavity and preventing excessive pressure accumulation. When the pressure in the sealing cavity does not exceed the pre-tightening force of the elastic sealing component, the elastic sealing component contacts the valve body and seals the vent to close the pressure relief channel and ensure the sealing performance of the sealing cavity. When applied to a cover plate with this pressure relief assembly in a battery, pressure relief can be achieved inside the battery cell, avoiding the problem of cover plate bulging and deformation caused by excessive internal pressure in the battery cell, thus solving the assembly difficulties and leakage risks caused by cover plate deformation. Attached Figure Description

[0021] Figure 1 This is a schematic diagram of the pressure relief assembly in a preferred embodiment of the present invention;

[0022] Figure 2This is a schematic diagram of the structure of the cover plate using the pressure relief component in a preferred embodiment of the present invention.

[0023] Figure 3 This is a schematic diagram of the structure of the cover plate with stress transfer component in a preferred embodiment of the present invention.

[0024] Figure 4 This is an enlarged schematic diagram of the stress transfer component in a preferred embodiment of the present invention.

[0025] Explanation of reference numerals in the attached figures:

[0026] 100. Pressure relief assembly; 101. Valve body; 102. Resilient sealing component; 103. Vent; 104. Flange; 105. Opening;

[0027] 200. Cover plate; 201. Cover plate body; 202. Explosion-proof grooves;

[0028] 300. Stress transfer assembly; 301. Stress shielding plate; 302. Structural adhesive. Detailed Implementation

[0029] The technical solutions of the present utility model will be clearly and completely described below with reference to the accompanying drawings of the embodiments. Obviously, the described embodiments are only some embodiments of the present utility model, and not all embodiments. Based on the embodiments of the present utility model, all other embodiments obtained by those of ordinary skill in the art without creative effort are within the protection scope of the present utility model.

[0030] It should be noted that, unless otherwise specified, the embodiments and features described in these embodiments can be combined with each other.

[0031] The present invention will be further described below with reference to the accompanying drawings and specific embodiments, but this is not intended to limit the present invention.

[0032] See Figure 1 In a preferred embodiment of the present invention, based on the above-mentioned problems existing in the prior art, a pressure relief assembly 100 is provided for pressure relief of a sealed cavity, including a valve body 101 and an elastic sealing component 102.

[0033] The valve body 101 is provided with an air hole 103 that communicates with the sealing cavity. One end of the air hole 103 communicates with the sealing cavity, and the other end communicates with the outer peripheral surface of the valve body 101.

[0034] The elastic sealing component 102 is fitted onto the outer circumferential surface of the valve body 101, and seals the vent 103. The elastic sealing component 102 can be made of rubber material, such as silicone rubber, fluororubber, or nitrile rubber. Preferably, the inner diameter of the elastic sealing component 102 is slightly smaller than the outer diameter of the valve body 101, so that the elastic sealing component 102 generates a pre-tightening force when fitted onto the valve body 101, thereby sealing the vent 103. The pre-tightening force of the elastic sealing component 102 can be controlled by adjusting the difference between the inner diameter of the elastic sealing component 102 and the outer diameter of the valve body 101.

[0035] When the pressure in the sealing cavity does not exceed the pre-tightening force of the elastic sealing member 102, the elastic sealing member 102 contacts the valve body 101 and seals the vent 103. Specifically, when the pressure in the sealing cavity is less than the pre-tightening force of the elastic sealing member 102, the elastic sealing member 102 adheres tightly to the outer circumferential surface of the valve body 101, sealing the vent 103 to prevent gas, liquid, or impurities from the external environment from entering the sealing cavity.

[0036] When the pressure in the sealing cavity exceeds the preload of the elastic sealing member 102, the elastic sealing member 102 partially separates from the valve body 101, forming a pressure relief channel connecting the sealing cavity to the external environment. Specifically, when the pressure inside the sealing cavity increases to exceed the preload of the elastic sealing member 102, the gas inside the sealing cavity pushes the elastic sealing member 102 outward through the vent 103, causing a gap to form between the elastic sealing member 102 and the outer peripheral surface of the valve body 101, thereby forming a pressure relief channel. The gas inside the sealing cavity is discharged to the external environment through the pressure relief channel, reducing the pressure inside the sealing cavity.

[0037] When the pressure inside the sealing cavity drops below the pre-tightening force of the elastic sealing component 102, the elastic sealing component 102 returns to its original shape under its own elasticity, re-adhere to the outer circumferential surface of the valve body 101, and seals the vent 103 to close the pressure relief channel.

[0038] More specifically, the valve body 101 can be made of a metallic material, such as steel, stainless steel, aluminum alloy, or copper alloy. Preferably, the valve body 101 can be made of steel.

[0039] More specifically, the valve body 101 can be designed as a cylinder with a cylindrical outer circumference. The vent 103 can be provided on the side wall of the valve body 101.

[0040] More specifically, the cylindrical valve body 101 has an opening 105 on one side, which communicates with both the vent 103 and the sealing cavity. An ear extends outward from the opening of the cylindrical valve body 101, forming a lug for connection and fixation with the outer shell of the sealing cavity, such as the cover plate that fits onto the sealing cavity shell as described below. This lug can be fixed to the sealing cavity shell by means including but not limited to interference fit, threaded connection, or welding.

[0041] Similarly, the resilient sealing component 102 can be designed as an annular ring, fitted onto the outer circumferential surface of the side wall of the valve body 101. The resilient sealing component 102 fully covers the location of the vent 103.

[0042] In a preferred embodiment, the vent 103 is inclined.

[0043] Specifically, the axis of the vent 103 forms an angle with the axis of the valve body 101, allowing gas to flow along the mating surface of the valve body 101 and the elastic sealing member 102, thereby pushing the elastic sealing member 102 to expand outward, thus forming a gap between the elastic sealing member 102 and the outer peripheral surface of the valve body 101.

[0044] The included angle can be from 30° to 60°, preferably 45°. In practical applications, it can be set according to the actual needs of the angle, and is not limited here.

[0045] More specifically, the vent can be one or more. Multiple vents are spaced apart along the outer circumferential surface of the side wall of the valve body 101.

[0046] In a preferred embodiment, the outer peripheral surface of the valve body 101 is provided with a flange 104, and a portion of the elastic sealing component 102 is sleeved on the flange 104.

[0047] Specifically, the flange 104 is a protrusion extending outward from the outer peripheral surface of the valve body 101, located at the upper or lower part of the side wall of the valve body 101. The resilient sealing member 102 covers the outer peripheral surface of the flange 104 and also covers the outer peripheral surface of the side wall of the valve body 101, covering the vent 103.

[0048] The flange helps to fix the position of the elastic sealing component 102 and prevent the elastic sealing component 102 from shifting due to expansion during the depressurization process.

[0049] More specifically, the vent 103 is inclined in a direction away from the flange, that is, the axis of the vent forms an angle with the axis of the valve body, and the outlet end of the vent is directed away from the flange.

[0050] The flange is located on the side of the vent 103 near the sealing cavity.

[0051] See Figure 2 In a preferred embodiment of the present invention, a cover plate 200 is also provided for covering a housing having a receiving cavity to form a sealed cavity. The cover plate 200 includes a cover plate body 201, on which a through hole is provided, and a pressure relief component 100 as described above is provided at the through hole.

[0052] More specifically, at least one through hole is formed in the cover plate body 201. The pressure relief assembly 100 is installed at the through hole and can be connected and fixed to the cover plate 200 by laser welding.

[0053] The valve body 101 of the pressure relief assembly 100 is positioned with the opening 105 facing the sealing cavity, allowing gas in the sealing cavity to enter the opening 105 and the vent 103.

[0054] Under normal circumstances, the pressure inside the sealing cavity is less than the pre-tightening force of the elastic sealing component 102 of the pressure relief assembly 100. The elastic sealing component 102 is in close contact with the outer peripheral surface of the valve body 101 to seal the vent 103.

[0055] When the pressure inside the sealing cavity increases to exceed the preload of the elastic sealing component 102, the gas inside the sealing cavity pushes the elastic sealing component 102 outward through the vent 103, causing a gap to form between the elastic sealing component 102 and the outer peripheral surface of the valve body 101, thereby forming a pressure relief channel. The gas inside the sealing cavity is discharged into the external environment through the pressure relief channel, reducing the pressure inside the sealing cavity.

[0056] When the pressure inside the sealing cavity decreases to less than the pre-tightening force of the elastic sealing component 102, the elastic sealing component 102 returns to its original shape under its own elasticity and re-adheres tightly to the outer circumferential surface of the valve body 101, sealing the vent 103.

[0057] More specifically, the pressure relief assembly 100 can be configured as one or more. When multiple pressure relief assemblies 100 are configured, the pressure relief assemblies 100 simultaneously release the gas inside the sealed cavity.

[0058] In a preferred embodiment, the cover plate body 201 is provided with a cover plate explosion-proof valve, and the pre-tightening force of the pressure relief assembly 100 is lower than the opening value of the cover plate explosion-proof valve.

[0059] Specifically, an explosion-proof valve is typically installed on the cover plate body 201 to release pressure through rupture or deformation when the pressure inside the sealed cavity exceeds a certain value, thus preventing the sealed cavity from exploding. The pressure relief assembly 100 is located within the diameter of the explosion-proof valve. The explosion-proof valve can be installed separately from the pressure relief assembly 100 or integrated with it.

[0060] The preload of the pressure relief assembly 100 is lower than the opening threshold of the explosion-proof valve. When the pressure inside the sealing chamber increases, the pressure relief assembly 100 is activated first to release some pressure. If the pressure relief assembly 100 cannot release enough pressure in time, and the pressure inside the sealing chamber continues to increase until it exceeds the opening threshold of the explosion-proof valve, then the explosion-proof valve will activate to release more pressure through a larger opening.

[0061] In a preferred embodiment, the cover plate body 201 has an explosion-proof groove area, and an explosion-proof groove 202 is provided in the explosion-proof groove area.

[0062] The explosion-proof notch 202 is usually located on the cover plate body 201 at the diameter position corresponding to the explosion-proof valve of the cover plate, that is, the pressure relief component 100 is also located inside the diameter of the explosion-proof notch.

[0063] By setting explosion-proof grooves, when the pressure inside the sealed cavity exceeds a certain value, the cover plate body 201 will break first at the explosion-proof grooves, forming an opening to release the pressure and preventing the sealed cavity from exploding in other locations.

[0064] Furthermore, the cover plate body 201 is provided with a stress transfer component 300, which transfers the pressure on the cover plate to the steel ring by means of stress transfer, thereby solving the problem of deformation under stress of the groove and avoiding leakage.

[0065] In a preferred embodiment, the cover plate body 201 is further provided with a stress shielding plate 301, which is disposed in the explosion-proof groove area and located at a position where the explosion-proof groove 202 is not opened.

[0066] Specifically, the stress transfer assembly 300 includes a stress shielding plate 301. The stress shielding plate 301 is disposed within the explosion-proof scoring area but does not cover the explosion-proof scoring 202; instead, it is located at a position where the explosion-proof scoring 202 is not formed. By adding the stress shielding plate 301 to the stress-weak area corresponding to the scoring, when the cover plate is deformed under pressure, the applied stress shielding plate 301 will form a stress shielding effect when the force is transmitted to the vicinity of the scoring area. Due to the stress shielding effect of the stress shielding plate 301, the force is transmitted to the stress shielding plate 301 without passing through the scoring. The stress shielding plate 301 acts as a force-bearing body, thereby protecting the weak scoring and avoiding the risk of cracking and leakage due to cover plate deformation.

[0067] Furthermore, through the stress conversion effect of the stress shielding plate 301, the depth of the explosion-proof groove 202 can be further increased during the groove design. For example, the thickness of the cover plate body 202 at the explosion-proof groove 202 can be reduced from 1 mm to 0.1 mm.

[0068] Furthermore, the stress shield 301 can be plate-shaped. The shape of the plate-shaped stress shield 301 can match the shape of the explosion-proof notch 202. For example, the explosion-proof notch 202 can be C-shaped, and similarly, the plate-shaped stress shield 301 can also be C-shaped. Of course, this is not the only limitation. In practical applications, the shape of the explosion-proof notch area and the layout of the explosion-proof notch can be designed according to the specific requirements, and no specific limitations are imposed here.

[0069] Furthermore, the stress shield 301 can be set to one, or it can be set to a number that corresponds one-to-one with the explosion-proof grooves 202.

[0070] Furthermore, the stress-shielding plate 301 can be disposed on one side of the cover plate body 201, such as on the inner side of the cover plate body 201 or on the outer side of the cover plate body 201. Alternatively, stress-shielding plates 301 can be disposed on both sides of the cover plate body 201.

[0071] More specifically, the stress shielding plate 301 may be made of a metallic material, such as steel.

[0072] In a preferred embodiment, the stress shielding plate 301 is attached to the explosion-proof groove area by structural adhesive 302.

[0073] Specifically, the stress shield 301 is adhered to the explosion-proof notch area using structural adhesive 302. The structural adhesive can be, but is not limited to, epoxy resin, polyurethane, or silicone.

[0074] When thermal runaway occurs in the battery cell, the internal temperature of the battery cell rises sharply. The structural adhesive 302 between the stress shielding plate 301 and the cover plate is melted by the high temperature and dissolved, so that the stress shielding plate 301 loses its stress shielding effect and thus does not affect the opening of the explosion-proof valve of the battery cell cover plate.

[0075] In a preferred embodiment of the present invention, a battery is also provided, the battery including a housing having a receiving cavity, characterized in that a cover plate 200 as described above is covered on the housing.

[0076] A cover plate 200 having the aforementioned pressure relief assembly 100 and / or stress transfer assembly 300 is used in the battery.

[0077] A pressure relief component 100, with a value lower than the opening valve, is added within the diameter of the explosion-proof valve on the cover plate. During battery use, the chemical reaction inside the battery produces gas, causing an increase in pressure within the sealed cavity. When the pressure within the sealed cavity is less than the pre-tightening force of the pressure relief component 100, the pressure relief component 100 is in the closed state. When the pressure within the sealed cavity increases to exceed the pre-tightening force of the pressure relief component 100, the pressure relief component 100 automatically opens, forming a pressure relief channel to expel the large amount of gas generated during battery cell use, maintaining constant pressure inside the battery cell and preventing the cover plate from bulging and deforming due to increased internal pressure, leading to risks such as inability to assemble and leakage due to scoring. When the pressure within the sealed cavity decreases to less than the pre-tightening force of the pressure relief component 100, the pressure relief component 100 automatically closes, resealing the sealed cavity.

[0078] By adding a stress transfer component 300 near the weak groove, when the cover plate is deformed under pressure, the applied stress shielding plate 301 will form a stress shielding effect, allowing the force to be transferred to the steel ring without passing through the groove, thus avoiding stress deformation on the groove. When thermal runaway occurs in the battery cell, the high temperature will melt the structural adhesive between the stress shielding plate 301 and the cover plate body 201, causing the stress shielding plate 301 to lose its stress shielding effect, thereby not affecting the opening of the battery cell cover plate.

[0079] In a preferred embodiment of the present invention, a battery pack is also provided, characterized in that the battery pack includes the battery as described above.

[0080] The advantages or beneficial effects of adopting the above technical solution are as follows: The pressure relief component of this utility model, by using a valve body and an elastic sealing component sleeved on the outer circumferential surface of the valve body, can control the pressure relief process according to the pressure change of the sealing cavity. When the pressure of the sealing cavity exceeds the pre-tightening force of the elastic sealing component, the elastic sealing component separates from the valve body to form a pressure relief channel connecting the sealing cavity with the external environment, thereby realizing the pressure relief of the sealing cavity and preventing excessive pressure accumulation. When the pressure of the sealing cavity does not exceed the pre-tightening force of the elastic sealing component, the elastic sealing component contacts the valve body and seals the air hole to close the pressure relief channel and ensure the sealing performance of the sealing cavity. When a cover plate with this pressure relief component is used in a battery, pressure relief inside the battery cell can be realized, avoiding the problem of cover plate bulging and deformation caused by excessive internal pressure of the battery cell, thereby solving the problems of assembly difficulties and leakage risks caused by cover plate deformation.

[0081] The above are merely preferred embodiments of the present utility model and are not intended to limit the implementation methods and protection scope of the present utility model. Those skilled in the art should realize that any equivalent substitutions and obvious changes made using the content of this specification and illustrations should be included within the protection scope of the present utility model.

Claims

1. A pressure relief assembly for pressure relief of a sealed cavity, characterized in that, include: A valve body, wherein the valve body is provided with an air hole communicating with the sealing cavity; An elastic sealing component is sleeved on the outer peripheral surface of the valve body, and the elastic sealing component seals the air hole. When the pressure in the sealing cavity exceeds the pre-tightening force of the elastic sealing component, the elastic sealing component separates from the valve body to form a pressure relief channel connecting the sealing cavity with the external environment. And when the pressure in the sealing cavity does not exceed the preload of the elastic sealing member, the elastic sealing member contacts the valve body and seals the air hole to close the pressure relief channel.

2. The pressure relief assembly of claim 1, wherein, The vents are set at an angle.

3. The pressure relief assembly of claim 1, wherein, The outer peripheral surface of the valve body is provided with a flange, and part of the elastic sealing component is sleeved on the flange; The vent is tilted away from the flange.

4. A cover plate for covering a housing having a receiving cavity to form a sealed cavity, characterized in that, The cover plate includes a cover plate body, the cover plate body has a through hole, and the through hole is provided with a pressure relief component as described in any one of claims 1-3.

5. The cover sheet of claim 4, wherein, The cover plate body is equipped with a cover plate explosion-proof valve, and the pre-tightening force of the pressure relief component is lower than the opening value of the cover plate explosion-proof valve.

6. The cover sheet of claim 5, wherein, The cover plate body has an explosion-proof etched area, and explosion-proof etched marks are made in the explosion-proof etched area.

7. The cover sheet of claim 6, wherein The cover plate body is also provided with a stress shielding plate, which is located in the explosion-proof groove area and at a position where no explosion-proof groove is opened.

8. The cover sheet of claim 7, wherein, The stress shielding plate is attached to the explosion-proof groove area using structural adhesive.

9. A battery comprising a case having a receiving cavity, characterized by The housing is covered with a cover plate as described in any one of claims 4-8.

10. A battery pack, characterized by, The battery pack includes the battery as described in claim 9.

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