Explosion-proof battery valve and battery

Abstract

The present application provides an explosion-proof battery valve and a battery. The explosion-proof battery valve comprises a protective shell (1), a piercing pin (2) and a diaphragm (3). The protective shell (1) comprises a shell body (11) and a protective cover (12) which are integrally connected by means of injection molding, wherein the shell body (11) is in the shape of a cylinder with two open ends, and radial exhaust holes (111) are formed in the peripheral wall of the shell body (11); the protective cover (12) is connected to one end opening of the shell body (11) in a plugged manner; and the other end opening of the shell body (11) is a pressure relief hole (113), and the pressure relief hole (113) communicates the radial exhaust holes (111) with the interior of a battery. The piercing pin (2) is arranged on the top wall of the protective cover (12), and is located in an inner cavity of the shell body (11). The diaphragm (3) is arranged in the pressure relief hole (113) in a covering manner, and gas discharged from the interior of the battery can drive the diaphragm (3) to deform towards the piercing pin (2), such that the diaphragm (3) is pierced by the piercing pin (2).

Description

Battery explosion-proof valve and battery

[0001] This application claims priority to the Chinese patent application filed with the China Patent Office on November 18, 2024, with application number 202411648537.9. The entire contents of the above application are incorporated by reference into this application.

[0002] Technical Field

[0003] The present application relates to the field of battery technology, and in particular to a battery explosion-proof valve and a battery.

[0004] Background Art

[0005] Batteries need to balance the external atmospheric pressure during daily use, and they need to quickly discharge the gas generated inside the battery under extreme thermal runaway conditions. A battery explosion-proof valve is usually installed on the battery casing to achieve the above functions.

[0006] Technical issues

[0007] Existing battery explosion-proof valves are mostly ejector-type, with the diaphragm exposed to the outside environment. During actual use, batteries may be installed in complex environments, such as contact with gravel and water impact, which can easily affect the diaphragm and cause it to fail. In related technologies, to improve the protection of the diaphragm, a protective cover is usually added to the housing. However, the housing and protective cover are usually produced separately and then assembled together, which complicates the manufacturing process and requires additional installation, increasing processing costs.

[0008] Technical Solutions

[0009] In a first aspect, an embodiment of the present application provides a battery explosion-proof valve, comprising:

[0010] A protective shell is configured to be mounted on a battery housing of a battery, the protective shell comprising a shell body and a protective cover integrally connected by injection molding, the shell body being cylindrical with openings at both ends, radial exhaust holes being provided on the outer peripheral wall of the shell body, the protective cover being sealed and connected to one end opening of the shell body, and the other end opening of the shell body being a pressure relief hole, the pressure relief hole communicating with the radial exhaust hole and the interior of the battery;

[0011] an ejector pin, disposed on the top wall of the protective cover and located in the inner cavity of the shell body;

[0012] A diaphragm is covered in the pressure relief hole, and the gas discharged from the battery can drive the diaphragm to deform toward the ejector pin, so that the diaphragm is punctured by the ejector pin.

[0013] In a second aspect, an embodiment of the present application provides a battery, comprising a battery housing and the battery explosion-proof valve as described above, wherein the protective shell is installed on the battery housing.

[0014] Beneficial effects

[0015] The present application provides a battery explosion-proof valve, which includes a protective shell, a ejector pin and a diaphragm, wherein the protective shell includes a shell body and a protective cover connected by integral injection molding, the shell body is cylindrical with openings at both ends, radial exhaust holes are provided on the outer peripheral wall of the shell body, the protective cover is sealed and connected to the opening at one end of the shell body, and the other end of the shell body is opened as a pressure relief hole, which connects the radial exhaust hole and the interior of the battery, the ejector pin is arranged on the top wall of the protective cover and is located in the inner cavity of the shell body, and the diaphragm covers the pressure relief hole. When thermal runaway occurs inside the battery, the gas discharged from the battery can drive the diaphragm to deform toward the ejector pin, so that the diaphragm is punctured by the ejector pin, so that the gas inside the battery can be quickly discharged through the pressure relief hole and the radial exhaust hole in sequence to achieve pressure relief. The battery explosion-proof valve provided by the present application is formed by integrally injecting the shell body and the protective cover, and no additional assembly is required between the shell body and the protective cover, which simplifies the processing technology of the battery explosion-proof valve, is easy to process and has low cost. In addition, since the diaphragm is covered in the pressure relief hole in the inner cavity of the shell body, and only radial exhaust holes are opened on the outer peripheral wall of the shell body, the protective shell provides protection for the diaphragm, effectively avoiding diaphragm failure and meeting the IP6K9K protection level.

[0016] The present application also provides a battery, which simplifies the processing technology of the battery explosion-proof valve by applying the above-mentioned battery explosion-proof valve, making it easy to process and low-cost, and effectively avoiding diaphragm failure, improving the protection effect of the diaphragm, and meeting the IP6K9K protection level.

[0017] BRIEF DESCRIPTION OF THE DRAWINGS

[0018] FIG1 is a schematic diagram of a first structure of a battery explosion-proof valve provided in an embodiment of the present application;

[0019] FIG2 is a second structural schematic diagram of a battery explosion-proof valve provided in an embodiment of the present application;

[0020] FIG3 is a cross-sectional view of the structure of a battery explosion-proof valve provided in an embodiment of the present application.

[0021] In the picture:

[0022] 20. Battery housing; 201. Mounting hole;

[0023] 1. Protective shell; 11. Shell body; 111. Radial exhaust hole; 112. Inner cavity; 113. Pressure relief hole; 114. Annular protrusion; 12. Protective cover; 13. Reinforcement rib; 14. Mounting portion; 141. Arc-shaped clamping plate; 1411. Abutment tongue;

[0024] 2. Ejector pin; 21. Connecting column; 211. Inner groove; 22. Needle head;

[0025] 3. Diaphragm;

[0026] 4. Sealing ring.

[0027] Modes for Carrying Out the Invention

[0028] As shown in Figures 1 to 3, this embodiment provides a battery explosion-proof valve, which includes a protective shell 1, a ejector pin 2 and a diaphragm 3, wherein the protective shell 1 is configured to be installed on a battery shell 20 of a battery, and the protective shell 1 includes a shell body 11 and a protective cover 12 that are integrally injection-molded. The shell body 11 is cylindrical with openings at both ends. A radial exhaust hole 111 is opened on the outer peripheral wall of the shell body 11. The protective cover 12 is sealed and connected to one end opening of the shell body 11. The other end opening of the shell body 11 is a pressure relief hole 113, which connects the radial exhaust hole 111 with the interior of the battery. The ejector pin 2 is provided on the top wall of the protective cover 12 and is located in the inner cavity 112 of the shell body 11. The diaphragm 3 covers the pressure relief hole 113. The gas discharged from the battery can drive the diaphragm 3 to deform toward the ejector pin 2, so that the diaphragm 3 is punctured by the ejector pin 2. The battery explosion-proof valve provided in this embodiment is capable of driving the diaphragm 3 to deform toward the ejector pin 2 when thermal runaway occurs inside the battery, so that the diaphragm 3 is punctured by the ejector pin 2, and the gas inside the battery can be quickly discharged in sequence through the pressure relief hole 113 and the radial exhaust hole 111, thereby achieving pressure relief. The battery explosion-proof valve provided in this embodiment is formed by integrally injection-molding the shell body 11 and the protective cover 12. No additional assembly is required between the shell body 11 and the protective cover 12, which simplifies the processing technology of the battery explosion-proof valve, facilitates processing, and is low in cost. In addition, since the diaphragm 3 covers the pressure relief hole 113 in the inner cavity 112 of the shell body 11, and only the radial exhaust hole 111 is opened on the outer peripheral wall of the shell body 11, the protective shell 1 provides good protection for the diaphragm 3, effectively avoiding failure of the diaphragm 3, and meeting the IP6K9K protection level.

[0029] In this embodiment, the diaphragm 3 is directly opposite to the ejector pin 2, and the diaphragm 3 is located on the side of the ejector pin 2 close to the battery housing 20, thereby ensuring that when thermal runaway occurs inside the battery, the gas discharged from the battery drives the diaphragm 3 to deform toward the ejector pin 2, thereby ensuring that the diaphragm 3 is punctured by the ejector pin 2.

[0030] In this embodiment, the diaphragm 3 is a breathable membrane. Under normal circumstances, the internal environment of the battery communicates with the external environment through the diaphragm 3 and radial vents 111, allowing for gas exchange. When thermal runaway occurs within the battery, the battery generates a large amount of gas, which prevents the internal gas from quickly passing through the diaphragm 3. As a result, the gas discharged from the battery drives the diaphragm 3 to deform toward the ejector pin 2, causing it to be punctured by the ejector pin 2. This ensures that the gas inside the battery can be quickly discharged through the pressure relief holes 113 and radial vents 111, achieving pressure relief.

[0031] In this embodiment, the diaphragm 3 is made of expanded polytetrafluoroethylene (E-PTFE). This material ensures that the diaphragm 3 is waterproof and breathable, enabling it to meet the battery's pressure balance requirements during daily use. It should be noted that the material of the diaphragm 3 limits the pore diameter of the diaphragm 3 to between 0.1 μm and 10 μm. This is in contrast to the average diameter of air molecules, which is only 0.00036 μm, the average diameter of water vapor, which is 0.00047 μm, and the diameter of drizzle, which is approximately 500 μm. This means that the pore diameter of the diaphragm 3 is over 1,000 times larger than the diameter of gas and a few thousandths smaller than a water droplet. Furthermore, due to the diaphragm 3's very low surface energy, surface tension (the pulling of water molecules against each other) causes small water droplets to quickly form larger beads on the surface of the diaphragm 3. This allows gas to pass smoothly through the diaphragm 3, while liquid water cannot. Consequently, the diaphragm 3 exhibits excellent waterproof and breathable properties.

[0032] In this embodiment, the diaphragm 3 is welded to the cavity wall of the protective shell 1, thereby ensuring the stability and tightness of the connection between the diaphragm 3 and the protective shell 1. In this embodiment, the diaphragm 3 and the cavity wall of the protective shell 1 can be connected using ultrasonic welding. Ultrasonic welding has the advantages of high control precision, high connection strength, stability and reliability, energy saving and environmental protection, high efficiency and low cost. In other embodiments, the diaphragm 3 and the cavity wall of the protective shell 1 can also be welded using heat welding or other welding methods.

[0033] In this embodiment, as shown in Figures 1 to 3, the ejector pin 2 is integrally injection-molded on the top wall of the protective cover 12. The above arrangement allows the housing body 11, the protective cover 12, and the ejector pin 2 to be integrally injection-molded, simplifying the process and facilitating processing while also ensuring the structural strength of the entire battery explosion-proof valve. It should be noted that in this embodiment, the protective cover 12 and the diaphragm 3 are spaced apart along the axial direction of the housing body 11, and the protective cover 12 and the diaphragm 3 are parallel to each other, thereby ensuring the protective blocking effect of the protective cover 12 on the diaphragm 3.

[0034] In this embodiment, as shown in Figures 1 to 3, the protective housing 1 further includes a mounting portion 14, which is connected to the end of the housing body 11 away from the protective cover 12. The mounting portion 14 is snap-fitted to the battery housing 20. By snapping the mounting portion 14 to the battery housing 20, the entire battery explosion-proof valve is easily installed and removed from the battery housing 20.

[0035] In this embodiment, the mounting portion 14 includes a plurality of arc-shaped clips 141 arranged at intervals along the circumference of the housing body 11. The arc-shaped clips 141 are connected to the end of the housing body 11 away from the protective cover 12. The end of each arc-shaped clip 141 is provided with an abutting tongue 1411, which is snap-fitted and mounted in the mounting hole 201 of the battery housing 20. When the mounting portion 14 is inserted into the mounting hole 201 of the battery housing 20, the plurality of arc-shaped clips 141 are squeezed inward by the wall of the mounting hole 201. When the mounting portion 14 is fully inserted into the mounting hole 201 of the battery housing 20, the plurality of arc-shaped clips 141 are elastically reset, and the abutting tongue 1411 is tightly pressed against the wall of the mounting hole 201, thereby ensuring that the mounting portion 14 is securely mounted in the mounting hole 201. When the mounting portion 14 needs to be removed from the mounting hole 201, the multiple arc-shaped clips 141 are squeezed inwardly to release the abutting tongues 1411 from the wall of the mounting hole 201. By designing the mounting portion 14 as a plurality of arc-shaped clips 141 spaced apart along the circumference of the housing body 11, the reliability of the connection of the mounting portion 14 in the mounting hole 201 is ensured, and the multiple arc-shaped clips 141 are also easily deformed.

[0036] In this embodiment, as shown in Figures 1 to 3, an annular protrusion 114 is provided on the outer circumferential wall of the housing body 11. The battery explosion-proof valve also includes a sealing ring 4, which is sleeved on the outer circumferential wall of the housing body 11 and sandwiched between the annular protrusion 114 and the battery housing 20. The provision of the sealing ring 4 ensures the airtightness of the entire battery explosion-proof valve at the battery housing 20. In some embodiments, the sealing ring 4 can be a VQM sealing ring, which has the advantages of high temperature resistance and good elasticity.

[0037] In this embodiment, the protective shell 1 further includes a plurality of reinforcing ribs 13, which are arranged at intervals along the circumference of the ejector pin 2. The reinforcing ribs 13 are connected between the outer wall of the ejector pin 2 and the top wall of the protective cover 12. The provision of the reinforcing ribs 13 ensures the connection strength between the ejector pin 2 and the protective shell 1, thereby ensuring the structural strength of the entire battery explosion-proof valve. In addition, the structural design of the reinforcing ribs 13 facilitates the integral injection molding of the shell body 11, the protective cover 12, and the ejector pin 2, and also avoids blockage of the radial exhaust holes 111, thereby ensuring the communication between the radial exhaust holes 111 and the pressure relief holes 113.

[0038] In this embodiment, as shown in Figure 3, a plurality of radial exhaust holes 111 are spaced apart along the circumference of the outer wall of the housing body 11. This arrangement improves exhaust efficiency. In this embodiment, the plurality of radial exhaust holes 111 are evenly spaced along the circumference of the housing body 11 to ensure uniform exhaust at multiple locations around the outer circumference of the housing body 11. In some embodiments, the radial exhaust holes 111 can be elliptical, rectangular, circular, or polygonal in shape.

[0039] In this embodiment, as shown in Figure 3, the ejector pin 2 includes a connecting column 21 and a needle head 22, wherein the connecting column 21 is disposed on the top wall of the protective cover 12, and the needle head 22 is configured to puncture the diaphragm 3. The connecting column 21 is provided with an inner groove 211 extending along the axial direction of the connecting column 21, and the inner groove 211 penetrates the protective cover 12. The structural design of the ejector pin 2 ensures the structural strength of the entire battery explosion-proof valve. In addition, the design of the inner groove 211 facilitates the integral injection molding of the entire protective shell 1 and the ejector pin 2, which also saves material costs.

[0040] This embodiment also provides a battery comprising a battery housing and the aforementioned battery explosion-proof valve, with a protective housing 1 mounted on the battery housing. By utilizing the aforementioned battery explosion-proof valve, the battery provided by this embodiment simplifies the manufacturing process of the battery explosion-proof valve, facilitating fabrication and reducing costs. It also effectively prevents failure of the diaphragm 3 and enhances the protective effect of the diaphragm 3. In this embodiment, a mounting hole 201 is defined in the battery housing, and the mounting portion 14 of the protective housing 1 is directly mounted in the mounting hole 201.

Claims

1. A battery explosion-proof valve, comprising: A protective shell (1), the protective shell (1) being configured to be mounted on a battery housing (20) of a battery, the protective shell (1) comprising a shell body (11) and a protective cover (12) connected by integral injection molding, the shell body (11) being cylindrical with both ends open, a radial exhaust hole (111) being provided on an outer peripheral wall of the shell body (11), the protective cover (12) being sealed and connected to one end opening of the shell body (11), the other end opening of the shell body (11) being a pressure relief hole (113), the pressure relief hole (113) being connected to the radial exhaust hole (111) and the interior of the battery; A thimble (2) is provided on the top wall of the protective cover (12) and is located in the inner cavity (112) of the shell body (11); and A diaphragm (3) is covered in the pressure relief hole (113), and the gas discharged from the battery can drive the diaphragm (3) to deform toward the ejector pin (2), so that the diaphragm (3) is punctured by the ejector pin (2).

2. The battery explosion-proof valve according to claim 1, wherein: The ejector pin (2) is integrally injection-molded on the top wall of the protective cover (12).

3. The battery explosion-proof valve according to claim 2, wherein: The protective shell (1) further comprises: A plurality of reinforcing ribs (13), wherein the plurality of reinforcing ribs (13) are arranged at intervals along the circumference of the ejector pin (2), and the plurality of reinforcing ribs (13) are connected between the outer wall of the ejector pin (2) and the top wall of the protective cover (12).

4. The battery explosion-proof valve according to any one of claims 1 to 3, wherein: A plurality of radial exhaust holes (111) are provided on the outer peripheral wall of the shell body (11) at intervals along the circumference thereof.

5. The battery explosion-proof valve according to any one of claims 1 to 3, wherein: The ejector pin (2) comprises a connecting column portion (21) and a needle head portion (22) connected to each other, wherein the connecting column portion (21) is arranged on the top wall of the protective cover (12), the needle head portion (22) is configured to puncture the diaphragm (3), and an inner groove (211) extending along the axial direction of the connecting column portion (21) is provided in the connecting column portion (21), and the inner groove (211) passes through the protective cover (12).

6. The battery explosion-proof valve according to any one of claims 1 to 3, wherein: The protective shell (1) further comprises: A mounting portion (14) is connected to an end of the housing body (11) away from the protective cover (12), and the mounting portion (14) is snap-fitted and mounted on the battery housing (20).

7. The battery explosion-proof valve according to claim 6, wherein: The mounting portion (14) comprises a plurality of arc-shaped clamping plates (141) arranged at intervals along the circumference of the shell body (11), the plurality of arc-shaped clamping plates (141) being connected to the end of the shell body (11) away from the protective cover (12), and an abutting tongue (1411) is provided at the end of each arc-shaped clamping plate (141), and the abutting tongue (1411) is clamped and mounted in the mounting hole (201) of the battery housing (20).

8. The battery explosion-proof valve according to any one of claims 1 to 3, wherein: An annular protrusion (114) is provided on the outer peripheral wall of the protective shell (1), and the battery explosion-proof valve further comprises a sealing ring (4), the sealing ring (4) being sleeved on the outer peripheral wall of the protective shell (1), and the sealing ring (4) being sandwiched between the annular protrusion (114) and the battery housing (20).

9. The battery explosion-proof valve according to any one of claims 1 to 3, wherein: The diaphragm (3) is connected to the cavity wall of the protective shell (1) by welding.

10. The battery explosion-proof valve according to any one of claims 1 to 3, wherein: The diaphragm (3) is a breathable membrane.

11. A battery, comprising a battery housing (20) and the battery explosion-proof valve according to any one of claims 1 to 10, wherein the protective shell (1) is mounted on the battery housing (20).

Images