Explosion-proof valve for a battery

Abstract

This application relates to an explosion-proof valve for batteries. The explosion-proof valve for batteries described in this application includes: a valve body, a diaphragm, a valve cover, a locking assembly, and a puncture-propelled assembly; the valve body has a tubular pressure relief channel, and the diaphragm and the valve cover are respectively installed at both ends of the valve body; the locking assembly is installed on the valve cover, and the puncture-propelled assembly is installed in the valve body and positioned between the diaphragm and the valve cover; when the diaphragm deforms due to the gas pressure generated by the battery, it pushes the puncture-propelled assembly to open the locking assembly, thereby unlocking the valve cover relative to the valve body; and the puncture-propelled assembly punctures the diaphragm, allowing the gas pressure generated by the battery to enter the pressure relief channel and force the valve cover out. The explosion-proof valve for batteries described in this application has the advantages of convenient pressure relief, good sealing effect, and controllable and adjustable pressure relief.

Description

Technical Field

[0001] This application relates to the field of power battery technology, and in particular to explosion-proof valves for batteries. Background Technology

[0002] In the field of battery technology, especially in the power battery system of new energy vehicles, the explosion-proof valve is not a dispensable component, but a core key component that balances battery sealing protection and thermal runaway safety. Its birth, iteration and application are entirely due to the multiple constraints of the power battery itself, the vehicle's usage environment and mandatory safety standards, and there is a complete and rigorous technical causal logic behind it.

[0003] From its origins, the core contradiction in the development of explosion-proof valves lies in the inherent conflict between the gas-generating characteristics of lithium batteries during thermal runaway and the sealing and waterproofing requirements of battery packs. Currently, the mainstream ternary lithium batteries and lithium iron phosphate batteries used in new energy vehicles are highly susceptible to thermal runaway reactions when experiencing faults such as cell overcharging, external compression, puncture, internal short circuits, or high-temperature aging. The electrolyte and positive and negative electrode materials inside the cell rapidly decompose, continuously producing large amounts of flammable and toxic gases such as hydrogen, carbon monoxide, hydrocarbons, and hydrogen fluoride, causing a rapid surge in internal pressure within the cell. Simultaneously, the power battery pack, as a high-voltage energy storage component of the vehicle, must meet IP67 or even IP68 waterproof and dustproof requirements, requiring a strictly sealed outer shell to prevent rainwater, dust, and moisture from entering and causing short circuits. The sealed shell structure completely confines the high-pressure flammable gas generated by thermal runaway inside the battery pack. As the gas continues to accumulate, the internal pressure will continue to exceed the shell's tolerance limit, causing the battery pack to bulge and rupture. The high-pressure flammable gas can easily cause deflagration and flame ejection after it leaks out instantly, directly threatening the safety of the occupants.

[0004] From a technological development perspective, explosion-proof valves for new energy vehicles have undergone four generations of technological iterations, with each upgrade addressing the safety defects and user pain points of the previous generation. The earliest first-generation product was a rupture disc type explosion-proof valve, which consisted of a thin, circular metal sheet with pre-marked grooves. Pressure was released by rupturing the grooves. This simple and inexpensive structure was widely used in early low-speed electric vehicles and early new energy vehicles. However, this type of product was a one-time pressure release structure. After rupture, the battery pack would lose its waterproof sealing capability, making it extremely susceptible to water ingress and damage. Furthermore, the pressure release flow was limited, making it difficult to cope with large-scale thermal runaway scenarios. The second generation was a one-way breathable membrane type explosion-proof valve. Its core component was a waterproof and breathable membrane, which allowed air to pass through but not water or dust under normal conditions. This was used to balance the air pressure inside and outside the battery pack and to cope with the thermal expansion and contraction of the shell caused by temperature changes and altitude changes. However, in the event of thermal runaway, the breathable membrane had weak impact resistance, slow pressure release speed, and small flow rate, making it unable to quickly discharge large amounts of high-pressure gas, still posing a risk of battery pack rupture. The third generation is a spring-piston explosion-proof valve, which is also the common solution for most mainstream automakers. It integrates a waterproof and breathable membrane with a spring piston dual structure. Under low-pressure conditions, it relies on the breathable membrane to achieve air pressure balance. Under thermal runaway high-pressure impact, it can directly push open the piston to achieve rapid pressure relief with a large flow rate. In some products, the piston can automatically reset after pressure relief, retaining waterproof performance and significantly improving safety redundancy. The fourth generation is the latest intelligent active explosion-proof valve, which integrates pressure and temperature sensors and electronic control actuators. It can monitor the battery pack status in real time, predict the risk of thermal runaway, and actively open to relieve pressure, no longer passively waiting for pressure triggering. It is the future development direction of high-end models and energy storage batteries.

[0005] From the perspective of practical function and application consequences, explosion-proof valves play three core roles: daily air pressure regulation, fault pressure relief and explosion prevention, and delaying the hazards of thermal runaway. During daily driving, changes in ambient temperature and vehicle altitude cause thermal expansion and contraction of the air inside the battery pack. The explosion-proof valve balances the internal and external air pressure through its venting structure, preventing deformation of the battery pack casing and aging and failure of the sealing strips, thus ensuring the long-term sealing performance of the battery pack. When a thermal runaway fault occurs in the power battery, the explosion-proof valve will immediately open the pressure relief channel to quickly release the high-pressure flammable gas inside, reducing the probability of the battery pack rupture, preventing high-pressure shock waves and large-scale deflagration, buying time for occupants to escape, and reducing the extent of vehicle fire damage. However, existing explosion-proof valves also have some significant problems. The venting membrane is easily clogged by dust, moisture, and battery volatiles over long-term use, causing pressure relief failure; the pressure relief port faces directly towards the vehicle chassis, posing a risk of igniting chassis wiring harnesses and pipelines from the leaked high-temperature flammable gas.

[0006] Overall, the complete cause-and-effect logic of explosion-proof valves for new energy vehicles is a clear closed loop: thermal runaway of the power battery will generate a large amount of gas, and the battery pack must be sealed and waterproof. If the gas cannot be discharged, it will cause an explosion safety accident, and explosion-proof valves have emerged to address this issue. As the safety standards for new energy vehicles continue to improve, explosion-proof valves have gradually upgraded from simple rupture discs to piston-type and intelligent active structures, continuously optimizing pressure relief efficiency and sealing reliability. Ultimately, the explosion-proof valve achieves a balance between battery pack sealing protection and thermal runaway safety, becoming an indispensable core component for ensuring the safe operation of new energy vehicles.

[0007] Existing explosion-proof valves either require high pressure to break through, making them difficult to break through and thus difficult to release pressure; or their sealing performance is not good enough, allowing insects or mud to enter; or their pressure release channels are too small, resulting in slow pressure release; and so on. Existing explosion-proof valves face many problems. Summary of the Invention

[0008] To address the problems of existing explosion-proof valves, such as difficulty in triggering pressure relief, insufficient sealing protection, small pressure relief flow, and slow response speed, this application provides an explosion-proof valve for batteries. This explosion-proof valve can achieve adjustable pressure relief, multiple sealing protection, rapid pressure relief with large flow, and linkage unlocking and puncture, and can reliably cope with high-pressure gas generation scenarios of battery thermal runaway, significantly improving the safety of battery use.

[0009] This application provides an explosion-proof valve for batteries, including a valve body, a diaphragm, a valve cover, a locking assembly, and a puncture-driving assembly. The valve body is a through-tube structure with an internal tubular pressure relief channel for rapid flow of high-pressure gas. A diaphragm and a valve cover are respectively installed at both ends of the valve body. The diaphragm serves as a pressure sensing and sealing component, while the valve cover serves as a normally closed and pressure-relief ejection component. The locking assembly is installed inside the valve cover and within the valve body, reliably locking the valve cover and valve body under normal conditions. The puncture-driving assembly is installed within the valve body, between the diaphragm and the valve cover, and receives pressure thrust, triggers unlocking, and performs a puncture action. When pressurized gas is generated inside the battery due to thermal runaway, the pressure pushes the diaphragm inward, causing it to deform. The diaphragm then pushes the puncture-driving assembly to move. The puncture-driving assembly first pushes the locking assembly open to both sides, releasing the valve cover from the valve body. Simultaneously, the puncture-driving assembly punctures the diaphragm, allowing airflow to rapidly enter the pressure relief channel and, under pressure, eject the valve cover, achieving instantaneous high-flow-rate pressure relief.

[0010] The diaphragm thickness can be changed, and the valve body channel size can also be adjusted to adapt to different air pressure and pressure relief requirements.

[0011] Furthermore, the mating contact surface between the valve cover and the valve body is provided with a sealing structure. This sealing structure can be a sealing ring, a sealing boss, or a sealing groove structure, which together with the diaphragm forms a double seal. The sealing ring can prevent external substances (water, mud, insects, dust, and corrosive substances) from entering the explosion-proof valve, thus meeting the high-level waterproof and dustproof requirements of the battery pack.

[0012] Furthermore, the driving puncture assembly includes a frame, a needle, and a driving block. The frame is securely mounted on the inner wall of the valve body, serving as a support and mounting base; the needle is fixedly mounted on the frame with its tip facing the diaphragm, used to puncture the diaphragm upon pressure relief triggering; the driving block is movably mounted on the frame and can move linearly in a set direction, used to receive the diaphragm's thrust and transmit power. Under normal conditions, the locking assembly limits and locks the valve cover to the frame, ensuring that the valve cover will not accidentally fall off due to vibration or bumps; when the diaphragm deforms under battery pressure, the diaphragm pushes the driving block to move, and the driving block then pushes the locking assembly to unlock and separate from the frame, allowing the valve cover to be in a free state that can be ejected.

[0013] Furthermore, a limiting groove is formed on the frame, and the end of the locking assembly is movably engaged in the limiting groove to achieve locking and positioning. The driving block and the frame are movably assembled, and the side of the driving block facing the locking assembly is provided with a ramp surface. This ramp surface is used to squeeze and push the locking assembly during movement, causing it to disengage from the limiting groove and complete unlocking. A through hole is formed on the driving block, which provides space for the needle to pass through, avoiding structural interference. When the diaphragm deforms and pushes the driving block to move, the driving block first completes the unlocking action. After continuous movement, the needle passes through the through hole and punctures the diaphragm, quickly opening the pressure relief path.

[0014] Furthermore, the limiting groove is a deep groove with columnar grooves;

[0015] Alternatively, the limiting groove can be a shallow groove. The limiting groove can have various depth specifications, with different depths corresponding to different unlocking air pressures and different levels of assembly tightness.

[0016] Furthermore, an inner wall sealing ring is formed on the inner sidewall of the valve body at the connection point with the valve cover. The inner wall sealing ring and the sealing structure of the end face form a double sealing effect for the valve cover, and the inner wall sealing ring, the sealing structure of the end face, and the diaphragm form a triple sealing effect.

[0017] Furthermore, the diaphragm is made of a flexible sealing material and is pressed and fixed to the inner wall of the valve body by an annular retaining ring. The retaining ring applies pressure evenly along the edge of the diaphragm to ensure that the diaphragm is installed flat and has a reliable seal, while preventing the diaphragm from falling off under air pressure. The diaphragm thickness can be flexibly adjusted according to the preset pressure relief, so as to achieve controllable and adjustable pressure relief.

[0018] Furthermore, the drive block is provided with a limiting post that extends through the frame. The limiting post constrains the movement direction of the drive block, ensuring it can only move in a straight line, preventing skewing or jamming during movement, and ensuring stable and reliable unlocking and piercing actions. Simultaneously, the limiting post also provides a connection between the drive block and the frame, guaranteeing assembly stability under normal conditions.

[0019] Furthermore, a mesh is provided at one end of the valve body near the diaphragm, located on the outside of the diaphragm, to support it. An end-face sealing ring is provided on the end face of the valve body near the diaphragm. During assembly, this sealing ring fits tightly against the surface of the battery casing, further strengthening the connection and seal between the valve body and the battery, and preventing leakage through gaps.

[0020] Furthermore, the locking assembly includes a sleeve, a spring, a locking pin, and a fastening block. The sleeve is fixedly installed on the inner wall of the valve cover, providing an installation cavity for internal parts; the locking pin, spring, and fastening block are sequentially assembled inside the sleeve from the inside out; a guide groove is provided on the side wall of the sleeve, and a protrusion on the locking pin extends from the guide groove to engage with the inclined surface of the drive block. The two ends of the spring abut against the locking pin and the fastening block respectively, providing an elastic clamping force to the locking pin, ensuring that the end of the locking pin stably abuts against the limiting groove of the frame. The fastening block is fixed to the end of the sleeve, serving a sealing and limiting function; when the drive block moves, its inclined surface pushes the protrusion on the locking pin, causing the locking pin to compress the spring and disengage from the limiting groove, thus unlocking the locking assembly from the valve body.

[0021] Furthermore, the tubular pressure relief channel of the valve body can adopt a round tube or a square tube structure. The round tube has low airflow resistance and smooth pressure relief, while the square tube structure has high strength and strong adaptability, and can be flexibly selected according to the battery pack installation space and pressure relief requirements.

[0022] Furthermore, the frame is fastened to the inner wall of the valve body by any of the following methods: fastening assembly, interference fit, or welding. It has high connection strength, is resistant to shock and impact, and ensures stable assembly under airflow impact.

[0023] Some beneficial effects of the present invention:

[0024] 1) Adjustable pressure relief. The thickness of the diaphragm can be customized and adjusted according to the preset pressure relief of the battery pack. The greater the thickness, the higher the air pressure required to trigger pressure relief, and the smaller the thickness, the more sensitive the triggering, accurately adapting to the safety pressure relief requirements of different battery models.

[0025] 2) Multiple sealing protection. The diaphragm and valve cover sealing structure form a double seal, which, together with the valve body end face sealing ring, constitutes a triple sealing system, effectively preventing mosquitoes, mud, sand and water vapor from entering, while not affecting the air pressure triggering response.

[0026] 3) High-flow-rate rapid pressure relief. The valve body adopts a through-type tubular pressure relief channel with a large diameter and low airflow resistance. In the event of thermal runaway, it can quickly discharge a large amount of high-pressure gas to prevent the battery pack from exploding.

[0027] 4) Linked unlocking and puncture. The locking assembly and the driving puncture assembly integrate locking and puncture functions. After the air pressure is triggered, the valve cover is unlocked first, and then the diaphragm is punctured. The action is smooth and without delay, achieving instantaneous pressure relief and greatly improving the explosion-proof safety performance.

[0028] To better understand and implement this application, the following detailed description is provided in conjunction with the accompanying drawings. Attached Figure Description

[0029] Figure 1 This is a three-dimensional structural schematic diagram of an explosion-proof valve for a battery, which is an example of this application.

[0030] Figure 2 This is a cross-sectional view of an exemplary explosion-proof valve for a battery according to this application;

[0031] Figure 3 This is a cross-sectional view of another exemplary explosion-proof valve for a battery in this application;

[0032] Figure 4 This is a three-dimensional structural schematic diagram of an exemplary explosion-proof valve for a battery, as shown in this application.

[0033] Figure 5 This is a three-dimensional structural diagram of an exemplary assembly structure of the locking component and the driving puncture component in this application.

[0034] Figure 6 This is a three-dimensional structural diagram of an exemplary valve cover and latch assembly of this application;

[0035] Figure 7 This is a three-dimensional structural diagram of an exemplary driving puncture component of this application;

[0036] Figure 8 This is an exemplary main view of the driving piercing component in this application;

[0037] Figure 9 This is a cross-sectional view of an exemplary drive puncture component of this application. Detailed Implementation

[0038] In the description of this application, it should be understood that the terms "center," "longitudinal," "lateral," "upper," "lower," "front," "rear," "left," "right," "vertical," "horizontal," "top," "bottom," "inner," and "outer," etc., indicating orientation or positional relationships based on the orientation or positional relationships shown in the accompanying drawings, are used only for the convenience of describing this application and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation, and therefore should not be construed as a limitation on this application. In the description of this application, unless otherwise stated, "a plurality of" means two or more.

[0039] Please see Figures 1-9 An explosion-proof valve for batteries according to this application includes a valve body 10, a diaphragm 30, a valve cover 20, a locking assembly, and a drive puncture assembly;

[0040] The valve body 10 has a tubular pressure relief channel, and the diaphragm 30 and the valve cover 20 are respectively installed at both ends of the valve body 10.

[0041] The locking assembly is mounted on the valve cover 20, and the driving puncture assembly is mounted inside the valve body 10 and positioned between the diaphragm 30 and the valve cover 20;

[0042] When the diaphragm 30 deforms due to the external air pressure, it pushes the drive puncture assembly to open the locking assembly, thereby unlocking the valve cover 20 relative to the valve body 10; and by driving the puncture assembly, the diaphragm 30 is punctured, allowing airflow to enter the pressure relief channel and push the valve cover 20 out.

[0043] The diaphragm exterior here refers to the common exterior of the valve body and the diaphragm. One way to generate air pressure is through the air pressure generated by the battery pack or battery compartment.

[0044] In some preferred embodiments, the driven puncture assembly includes a skeleton 52, a needle 51, and a drive block 40;

[0045] The frame 52 is installed on the inner wall of the valve cover 20, the needle 51 is installed on the frame 52, and the tip of the needle 51 faces the diaphragm 30; the needle 51 is used to puncture the diaphragm 30; the drive block 40 is movably assembled on the frame 52.

[0046] The locking assembly limits and locks the valve cover 20 onto the frame 52. When the diaphragm 30 deforms due to the air pressure outside the diaphragm, it pushes the drive block 40 to unlock and separate the locking assembly from the frame 52, thereby unlocking the valve cover 20 from the valve body 10.

[0047] In some preferred embodiments, a limiting groove B is formed on the skeleton 52, and one end of the locking assembly is movably abutted in the limiting groove B;

[0048] The drive block 40 is movably assembled with the frame 52, and the ramp of the drive block 40 is used to push the locking assembly to separate from the limiting groove B;

[0049] A through hole is formed on the drive block 40. When the diaphragm 30 deforms and pushes the drive block 40 to move, the drive block 40 pushes the locking assembly to unlock and continues to push the drive block 40, so that the tip of the piercing needle 51 passes through the through hole and punctures the diaphragm 30.

[0050] In some preferred embodiments, a sealing structure 61 is formed on the contact surface between the valve cover 20 and the valve body 10, which forms a double seal with the diaphragm 30. In some further embodiments, the sealing structure 61 is an end sealing ring.

[0051] In some preferred embodiments, the limiting groove is a deep groove with columnar grooves;

[0052] Alternatively, the limiting groove may be a shallow groove. A shallow groove has no columnar groove, only a groove that mates with the end face of the locking post 21. A deep groove has at least one columnar groove section, and may also include a groove that matches the shape of the end face of the locking post. For example, a deep groove may have only one columnar groove, or it may be a combination of a columnar groove and an end face groove. A shallow groove has only one end face groove.

[0053] The cross-sectional shape of the end face groove can be circular, conical, or irregular. For deep groove designs, the end face shape of the locking post 21 can match or not match the end face groove shape of the deep groove; neither will affect the alignment and assembly of the locking post and the limiting groove. For shallow groove designs, the end face shape of the locking post 21 needs to match the end face groove shape of the shallow groove to ensure the tightness of the alignment and assembly.

[0054] The deep groove is a structure in which the shape of the columnar groove matches the shape of the end face. It is advisable that the shape of the columnar groove matches the shape of the locking post 21. In the deep groove scheme, when the locking post 21 and the limiting groove are locked, the assembly tightness is better and it is relatively not easy to loosen, thereby ensuring good assembly tightness between the valve cover and the valve body.

[0055] Compared to the deep groove, the shallow groove provides acceptable but not high tightness for the assembly of the locking post 21 and the limiting groove. Therefore, the tightness of the assembly between the valve cover and the valve body can be improved by setting a sealing structure.

[0056] In some preferred embodiments, an inner wall sealing ring 63 is formed on the inner sidewall of the valve body at the connection with the valve cover. The inner wall sealing ring 63 is provided to increase the tightness of the connection between the valve body and the valve cover and to enhance the assembly sealing effect.

[0057] Based on this, there are at least six ways to combine the limiting groove and the seal in this application.

[0058] Firstly, a sealing structure 61 is provided at the end of the valve body, and the limiting groove is a deep groove; this combination method is as follows: Figure 2 As shown,

[0059] Secondly, the end face of the valve body is provided with a sealing structure 61, and the limiting groove is a shallow groove.

[0060] Thirdly, the inner wall of the valve body is provided with an inner wall sealing ring 63, and the limiting groove is a deep groove;

[0061] Fourth, the inner wall of the valve body is provided with an inner wall sealing ring 63, and the limiting groove is a shallow groove.

[0062] Fifth, the valve body is provided with a sealing structure 61 at its end, and an inner wall sealing ring 63 is provided on its inner wall, and the limiting groove is a deep groove.

[0063] Sixth, a sealing structure 61 is provided at the end of the valve body, and an inner wall sealing ring 63 is provided on its inner wall. The limiting groove is a shallow groove; this combination method is as follows. Figure 3 As shown.

[0064] In some preferred embodiments, the diaphragm 30 is fastened to the inner wall of the valve body 10 by an annular retaining ring 31.

[0065] In some preferred embodiments, the drive block 40 is limited to the frame 52 by a limiting post 41, which extends through the frame 52 to limit the direction of movement of the drive block 40 relative to the frame 52.

[0066] In some preferred embodiments, a mesh 11 is formed at the end of the valve body 10 located on the same side as the diaphragm 30; the mesh 11 is located on one side of the diaphragm 30;

[0067] An end face sealing ring 62 is formed on the end face of the valve body 10 located on the same side as the diaphragm 30. This sealing ring is used to strengthen the sealing of the connection surface between the valve body 10 and the battery.

[0068] In some preferred embodiments, the locking assembly includes a sleeve 25, a spring 22, a locking post 21, and a fastening block 23;

[0069] The sleeve 25 is fixed to the inner wall of the valve cover 20;

[0070] The locking pin 21, the spring 22, and the fastening block 23 are sequentially assembled into the sleeve 25; the side wall of the sleeve 25 is formed with a guide groove, and the protrusion 24 of the locking pin 21 extends out of the guide groove;

[0071] The two ends of the spring 22 respectively abut against the locking post 21 and the fastening block 23;

[0072] The fastening block 23 is fastened to the end of the sleeve 25;

[0073] The end of the locking post 21 extends out of the sleeve 25 and movably abuts against the limiting groove B of the frame 52;

[0074] The inclined surface of the drive block 40 is used to push the protrusion 24 of the locking post 21 to separate the locking post 21 from the limiting groove B, so that the locking assembly is unlocked from the valve body 10.

[0075] In some preferred embodiments, the pressure relief channel is tubular, either round or square.

[0076] In some preferred embodiments, the skeleton 52 is mounted on the inner wall of the valve body 10 by any of the following methods: close contact, interference fit, or welding.

[0077] The following provides a specific example to better understand the technical solution of this application.

[0078] An explosion-proof valve for batteries includes a valve body 10, a diaphragm 30, a valve cover 20, a locking assembly, and a puncture-propelled assembly. The valve body 10 has a tubular pressure relief channel, with the diaphragm 30 and valve cover 20 respectively mounted at both ends. The locking assembly is mounted on the valve cover 20, and the puncture-propelled assembly is installed inside the valve body 10, located between the diaphragm 30 and the valve cover 20. When the gas pressure generated by the battery increases, causing the diaphragm 30 to deform, it pushes the puncture-propelled assembly to open the locking assembly, unlocking the valve cover 20 from the valve body 10. Simultaneously, the puncture-propelled assembly punctures the diaphragm 30, allowing high-pressure gas to enter the pressure relief channel and eject the valve cover 20, thus completing rapid pressure relief.

[0079] The contact surface between the valve cover 20 and the valve body 10 is provided with a sealing structure, which forms a double seal with the diaphragm 30, thereby improving the overall protection performance.

[0080] The puncture drive assembly includes a frame 52, a needle 51, and a drive block 40. The frame 52 is fixed to the inner wall of the valve body 10, the needle 51 is mounted on the frame 52 with its tip facing the diaphragm 30, and the drive block 40 is movably mounted on the frame 52. The locking assembly locks the valve cover 20 onto the frame 52. When the diaphragm 30 deforms, it pushes the locking assembly to unlock from the frame 52, and the valve cover 20 is unlocked accordingly.

[0081] The frame 52 has a limiting groove B, and the end of the locking assembly is engaged in the limiting groove B; the drive block 40 has a ramp and a through hole. When the diaphragm 30 pushes the drive block 40 to move, the ramp pushes the locking assembly to disengage from the limiting groove B, and the needle 51 passes through the through hole and punctures the diaphragm 30.

[0082] The diaphragm 30 is secured to the inner wall of the valve body 10 by an annular retaining ring 31, ensuring a firm installation and reliable seal. The drive block 40 is connected to the frame 52 via a limiting post 41, ensuring stable movement.

[0083] The valve body 10 has a mesh 11 and an end face sealing ring 62 on the side of the diaphragm 30. The mesh 11 protects the diaphragm 30, and the end face sealing ring 62 strengthens the installation seal.

[0084] The locking assembly consists of a sleeve 25, a spring 22, a locking post 21, and a fastening block 23. The sleeve 25 is fixed to the valve cover 20. The locking post 21 is locked into the limiting groove B under the action of the spring 22. The inclined surface of the drive block 40 pushes the locking post 21 to unlock.

[0085] The pressure relief channel can be made of round or square tube, and the frame 52 is fixed by interference fit or welding. The overall structure is stable and the pressure relief response is rapid.

[0086] During assembly, the diaphragm 30 is first fixed to one end of the valve body 10 using the retaining ring 31. Then, the frame 52 is fixed inside the valve body 10. The drive block 40, the piercing needle 51, the locking assembly, and the valve cover 20 are then assembled in sequence, so that the locking pin 21 is engaged with the limiting groove B to complete the locking. In use, the end of the valve body 10 with the sealing ring is sealed to the battery housing. Under normal conditions, multiple seals ensure the protection level. When thermal runaway high voltage is triggered, the deformation of the diaphragm 30 drives the unlocking and piercing, and the valve cover 20 is ejected to achieve rapid pressure relief and ensure battery safety.

[0087] The embodiments described above are merely examples of several implementation methods of this application, and while the descriptions are relatively specific and detailed, they should not be construed as limiting the scope of the patent application. It should be noted that those skilled in the art can make various modifications and improvements without departing from the concept of this application, and these modifications and improvements all fall within the protection scope of this application.

Claims

1. An explosion-proof valve for batteries, characterized in that: Includes valve body, diaphragm, valve cover, locking assembly, and drive puncture assembly; The valve body has a tubular pressure relief channel, and the diaphragm and the valve cover are respectively installed at both ends of the valve body; The locking assembly is mounted on the valve cover, and the driving puncture assembly is mounted in the valve body and positioned between the diaphragm and the valve cover; When the diaphragm deforms due to external air pressure, it pushes the puncture assembly to open the locking assembly, thus unlocking the valve cover relative to the valve body; and the puncture assembly punctures the diaphragm, allowing airflow to enter the pressure relief channel and push the valve cover out.

2. The explosion-proof valve for batteries according to claim 1, characterized in that: The driving puncture assembly includes a skeleton, a needle, and a driving block; The skeleton is installed on the inner wall of the valve cover, the needle is installed on the skeleton with the tip of the needle facing the diaphragm; the needle is used to puncture the diaphragm; the drive block is movably assembled on the skeleton; The locking assembly locks the valve cover onto the frame. When the diaphragm deforms due to external air pressure, it pushes the drive block to unlock and separate the locking assembly from the frame, thus unlocking the valve cover from the valve body.

3. The explosion-proof valve for batteries according to claim 2, characterized in that: A limiting groove is provided on the frame, and one end of the locking assembly is movably abutted in the limiting groove; The drive block is movably assembled with the skeleton, and the ramp of the drive block is used to push the locking assembly to separate from the limiting groove; A through hole is formed on the drive block. When the diaphragm deforms and pushes the drive block to move, the drive block pushes the locking assembly to unlock. The drive block continues to push, causing the tip of the needle to pass through the through hole and puncture the diaphragm.

4. The explosion-proof valve for batteries according to claim 3, characterized in that: The limiting groove is a deep groove with columnar grooves; Alternatively, the limiting groove may be a shallow groove.

5. The explosion-proof valve for batteries according to claim 4, characterized in that: A sealing structure is formed on the contact surface between the valve cover and the valve body, and this sealing structure forms a double seal with the diaphragm.

6. The explosion-proof valve for batteries according to claim 4, characterized in that: An inner wall sealing ring is formed on the inner side wall of the valve body and at the connection with the valve cover.

7. The explosion-proof valve for batteries according to claim 3, characterized in that: The diaphragm is fastened to the inner wall of the valve body by an annular retaining ring.

8. The explosion-proof valve for batteries according to claim 3, characterized in that: The drive block is connected to the frame by a limiting post, which moves through the frame to limit the direction of movement of the drive block relative to the frame.

9. The explosion-proof valve for batteries according to claim 3, characterized in that: The locking assembly includes a sleeve, a spring, a locking pin, and a fastening block; The sleeve is fixed to the inner wall of the valve cover; The locking pin, the spring, and the fastening block are sequentially assembled into the sleeve; a guide groove is formed on the side wall of the sleeve, and the protrusion of the locking pin extends out of the guide groove; The two ends of the spring respectively abut against the locking post and the fastening block; The fastening block is securely installed at the end of the sleeve; The end of the locking pin extends out of the sleeve and movably abuts against the limiting groove of the frame; The inclined surface of the drive block is used to push the protrusion of the locking post to separate the locking post from the limiting groove, thereby unlocking the locking assembly from the valve body.

10. The explosion-proof valve for batteries according to any one of claims 3-9, characterized in that: A mesh is formed at the end of the valve body located on the same side of the diaphragm; the mesh is located on one side of the diaphragm. An end face sealing ring is formed on the end face of the valve body located on the same side of the diaphragm. This sealing ring is used to strengthen the sealing of the connection surface between the valve body and the battery. The skeleton is installed on the inner wall of the valve body by any of the following methods: close contact, interference fit, or welding.

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