Explosion-proof valve and battery pack
By designing a combination of valve body, guide rod, spring and waterproof and breathable membrane for the explosion-proof valve, the problems of unrecoverable and functional failure of existing explosion-proof valves are solved, achieving waterproof, breathable and reliable pressure relief effects, improving battery safety and space utilization.
Patent Information
- Application Number
- CN202520078022.3
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- Filing Date
- 2025-01-14
- Publication Date
- 2026-02-27
- Estimated Expiration
- 2035-01-14
AI Technical Summary
Existing explosion-proof valves cannot be restored after pressure relief, resulting in functional failure, high cost, and difficulty in simultaneously meeting the requirements of waterproofing, breathability, and reliable pressure relief, affecting the performance and safety of batteries in various environments.
An explosion-proof valve was designed, including a valve body, a guide rod, a spring, a waterproof and breathable membrane, and a sealing ring. The valve achieves reliable sealing and pressure relief functions through the cooperation of the limiting step and the sealing ring. The design of the "7"-shaped airflow channel and the elastic diaphragm ensures breathability and stability.
It achieves the requirements of waterproofing, breathability, and reliable pressure relief, simplifies the structural design, improves the reliability and space utilization of the explosion-proof valve, and ensures the performance and safety of the battery in various environments.
Smart Images
Figure CN223956754U_ABST
Abstract
Description
TECHNICAL FIELD
[0001] The utility model relates to battery manufacturing technical field especially relates to a kind of explosion-proof valve and battery package. BACKGROUND
[0002] When short circuit, overcharge, overdischarge and other abnormal conditions occur during the use of power battery, a large amount of gas will be generated inside the battery due to the reaction, causing the pressure inside the battery to increase rapidly, leading to deformation of the battery shell or even the risk of explosion. Therefore, an explosion-proof valve is usually installed on the battery shell. When the pressure inside the battery increases to a certain pressure value, the explosion-proof valve opens, thereby releasing the gas inside the battery to relieve pressure.
[0003] The existing explosion-proof valve generally cannot recover to the original state after the pressure relief action, resulting in functional failure and the need for frequent replacement, which has the disadvantages of high cost and inconvenience of use. Moreover, the existing explosion-proof valve cannot effectively meet the requirements of waterproofing, air permeability and reliable pressure relief at the same time, affecting the performance and safety of the battery in various environments. SUMMARY
[0004] The utility model aims at providing an explosion-proof valve that can effectively meet the requirements of waterproofing, air permeability and reliable pressure relief at the same time, ensuring the performance and safety of the battery in various environments.
[0005] The utility model achieves the above-mentioned purpose by adopting the following technical solutions:
[0006] An explosion-proof valve is installed on a target shell and includes:
[0007] A valve body has a first cavity extending inward from the side wall and a second cavity extending inward from the bottom surface, wherein the first and second cavities are connected, and a limiting step is provided in front of the connection point of the first cavity;
[0008] A guide rod is movably arranged in the first cavity, and a first sealing ring is arranged on the guide rod;
[0009] A spring is arranged in the first cavity, and the spring is used to apply a backward load to the guide rod;
[0010] A waterproof and air-permeable film is arranged below the second cavity;
[0011] In the natural state, the guide rod tightly presses the first sealing ring against the limiting step to form a seal. When the air pressure inside the target shell is greater than the load of the spring, the guide rod moves forward, causing the first sealing ring to separate from the limiting step and release pressure.
[0012] The explosion-proof valve can effectively meet the requirements of waterproofing, air permeability and reliable pressure relief at the same time, and ensure the performance and safety of the battery in various environments. Moreover, the waterproof and air-permeable film is arranged away from the guide rod, which simplifies the structure design and avoids accidental damage to the waterproof and air-permeable film caused by the installation or use of the valve rod, thereby improving the reliability of the function of the explosion-proof valve.
[0013] In some embodiments, the first cavity is arranged transversely, and the second cavity is arranged obliquely, and the two cavities are communicated to form a "7"-shaped air flow channel.
[0014] In the above scheme, by transversely installing the guide rod in the first cavity and obliquely arranging the second cavity to shorten the distance from the bottom surface to the top surface of the valve body 1, the volume of the valve body is greatly reduced while meeting the functional requirements, thereby saving space.
[0015] In some embodiments, the limiting step includes an inclined matching surface, and the angle between the matching surface and the horizontal plane is 110°-130°.
[0016] In the above scheme, if the angle is less than 110°, the contact area between the matching surface and the first sealing ring is small, and the sealing performance is difficult to maintain in a good state. If the angle is greater than 130°, the limiting effect of the matching surface on the first sealing ring decreases, which may cause the first sealing ring to pass over the limiting step and result in sealing. When the angle between the matching surface and the horizontal plane is 110°-130°, the sealing effect formed by the first sealing ring and the matching surface is better.
[0017] In some embodiments, the rear part of the guide rod is provided with spaced first and second convex ring parts, the spring is located on the front side of the first convex ring part, and the first sealing ring is located between the first and second convex ring parts.
[0018] In the above scheme, by providing the first and second convex ring parts, the installation and positioning of the spring and the first sealing ring are facilitated.
[0019] In some embodiments, the first and second convex ring parts are respectively arranged in the first and second cavity sections of the first cavity, and the outer periphery of each of the first and second convex ring parts is provided with a gas guide groove.
[0020] In the above scheme, either of the first and second convex ring parts can guide the movement of the guide rod in a small range, so as to improve the stability during pressure relief switching, and the gas guide groove is provided to ensure the smoothness of the air flow channel.
[0021] In some embodiments, the front end of the first cavity is provided with a hollow rivet column, and the rivet column is used for fixing the spring and assisting the movement of the guide rod.
[0022] In some embodiments, the inner side of the rivet column is circumferentially and evenly distributed with a plurality of elastic membrane petals; in a natural state, each of the elastic membrane petals is closed but leaves a ventilation gap between adjacent elastic membrane petals, and when the air pressure in the target shell is greater than the loading force of the spring, the guide rod moves forward to force each of the elastic membrane petals to open to form a ventilation flow channel.
[0023] In the above scheme, the elastic membrane petals can prevent large-diameter impurities from entering the first cavity channel at ordinary times, ensure normal use of the valve function, and adaptively control the flow according to the gas flow when pressure relief, thereby achieving the function of rapid exhaust pressure relief.
[0024] In some embodiments, the front end of the guide rod is hollow, or the front end of the guide rod is provided with a gas guide hole extending to the middle part of the rod body.
[0025] In the above scheme, the hollow design of the front end of the guide rod or the gas guide hole design can guide more gas to flow from the first cavity channel to the outside of the elastic membrane petals, thereby further strengthening the exhaust pressure relief function.
[0026] In some embodiments, a second sealing ring is arranged between the valve body and the target shell, and the second sealing ring is located at the outer periphery of the waterproof and breathable membrane.
[0027] In the above scheme, the second sealing ring is used to improve the sealing performance between the valve body and the target shell, prevent external water vapor from entering the interior of the target shell, and affect the service life.
[0028] In some embodiments, the bottom surface of the valve body is further provided with a welding structure; the welding structure comprises a boss arranged at the outer edge of the bottom surface of the valve body, and a conical protrusion arranged at the lower end of the boss.
[0029] In the above scheme, the welding structure can increase the contact area of welding and make the stress at the welding seam more uniform, thereby improving the welding quality and strength.
[0030] In some embodiments, the explosion-proof valve is configured to have a pressure relief range of 0.1 MPa to 0.2 MPa and an explosion relief range of 0.3 MPa to 0.8 MPa.
[0031] The utility model also provides a battery pack comprising the above explosion-proof valve.
[0032] Compared with the prior art, the utility model has at least the following beneficial effects:
[0033] 1. The explosion-proof valve can effectively meet the requirements of waterproofing, ventilation and reliable pressure relief, and ensure the performance and safety of the battery in various environments.
[0034] 2、The waterproof and breathable film is arranged away from the guide rod, which simplifies the structural design, avoids accidental damage to the waterproof and breathable film caused by installation or use of the valve rod, and improves the reliability of the explosion-proof valve function.
[0035] 3、The "7" type air flow channel design meets the functional requirements while greatly reducing the size of the valve body, thereby saving space.
[0036] 4、The double convex ring part on the guide rod can fix the first sealing ring and guide, thereby improving the stability of movement.
[0037] 5、The elastic membrane flap can prevent large-particle impurities from entering the first cavity channel, ensure normal use of the valve function, and automatically control the flow according to the gas flow during pressure relief, thereby realizing the function of rapid exhaust and pressure relief. BRIEF DESCRIPTION OF DRAWINGS
[0038] Figure 1 is a schematic diagram of the three-dimensional structure of the explosion-proof valve of the utility model.
[0039] Figure 2 is a schematic diagram of the cross-sectional structure of the explosion-proof valve.
[0040] Figure 3 is a schematic diagram of the structure inside the valve body.
[0041] Figure 4 is a schematic diagram of the structure of the guide rod.
[0042] Figure 5 is a schematic diagram of the distribution of the elastic membrane flap in the rivet column.
[0043] Figure 6 is a schematic diagram of the cooperation of the guide rod and the elastic membrane flap.
[0044] Figure 7 is a schematic diagram of the structure of the battery pack of the utility model.
[0045] In the figure: 1, valve body; 11, first cavity channel; 111, first cavity section; 112, second cavity section; 12, second cavity channel; 13, limiting step; 131, matching surface; 2, guide rod; 21, first convex ring part; 22, double convex ring part; 23, air guide hole; 3, first sealing ring; 4, spring; 5, waterproof and breathable film; 6, air guide groove; 7, rivet column; 8, elastic membrane flap; 9, second sealing ring; 10, welding structure; 101, convex table; 102, conical protrusion. DETAILED DESCRIPTION
[0046] Example implementations will now be described more fully with reference to the accompanying drawings. Example implementations may, however, be implemented in many different forms and should not be construed as limited to the implementations set forth herein; rather, these implementations are provided so that this disclosure will be thorough and complete, and fully convey the inventive aspects of the example implementations to those skilled in the art. Like reference numerals refer to like elements throughout the several views and the description of the figures should not be construed as limiting.
[0047] The words expressing position and direction described in the present application are illustrated by taking the drawings as an example, but changes can also be made according to needs, and the changes made are included in the protection scope of the present application.
[0048] The present application relates to Figures 1 to 4 As shown in the figure, the present application discloses an explosion-proof valve, which is installed on a target shell and comprises a valve body 1, a guide rod 2, a first sealing ring 3, a spring 4 and a waterproof air-permeable film 5.
[0049] The valve body 1 is substantially cylindrical in structure and can be fixed on the target shell, such as a battery shell, by welding (see Figure 7 ). The valve body 1 has a first cavity 11 extending inward from the side wall and a second cavity 12 extending inward from the bottom surface (see Figure 3 ), and the first and second cavities 11 and 12 are connected, so that a controllable airflow passage is formed between the target shell and the external atmosphere.
[0050] In addition, a limiting step 13 is arranged in front of the connecting part of the first cavity 11, which is used to cooperate with the first sealing ring 3 to achieve sealing (see Figure 2 ). In this application, the limiting step 13 can be formed by connecting a first cavity section 111 and a second cavity section 112 with different diameters, wherein the first cavity section 111 is also used to install the spring 4 and the main part of the guide rod 2, and the second cavity section 112 is used to connect the second cavity 12.
[0051] The guide rod 2 is movably arranged in the first cavity 11, for example, moving back and forth along the length direction of the first cavity 11, and the first sealing ring 3 is arranged on the guide rod 2. The first sealing ring 3 moves synchronously with the guide rod 2, and can form a seal with the limiting step 13 after being squeezed, thereby cutting off the first cavity 11 and preventing external water vapor or impurities from entering and affecting or damaging the components in the target shell.
[0052] A spring 4 is also arranged in the first cavity 11, one end of which is fixed and the other end of which is connected to the guide rod 2. In the present application, a hollow rivet column 7 can be arranged at the front end of the first cavity 11, and a first protruding ring portion 21 is arranged at the rear portion of the guide rod 2, and the spring 4 is arranged between the rivet column 7 and the first protruding ring portion 21. It should be noted that the elasticity is designed to be in a compressed state, which enables it to apply a rearward loading force (elastic force) to the guide rod 2, thereby pressing the first sealing ring 3 against the limiting step 13.
[0053] The waterproof and breathable membrane 5 is arranged below the second cavity 12, for example, the waterproof and breathable membrane 5 can be welded to the bottom surface of the valve body 1 and cover the air port of the second cavity 12, so as to prevent external moisture from entering the interior of the target shell, but does not affect the release of the gas in the interior of the target shell to the outside.
[0054] It is worth mentioning that the waterproof and breathable membrane 5 is arranged away from the guide rod 2 in the present application, which simplifies the structural design and can avoid accidental damage to the waterproof and breathable membrane 5 during the installation or use of the valve stem, thereby improving the reliability of the function of the explosion-proof valve.
[0055] Still referring to Figure 2 The principle of the explosion-proof valve is as follows:
[0056] In a natural state, the guide rod 2 can press the first sealing ring 3 against the limiting step 13 to form a seal by means of the loading force generated by the compression of the spring 4. A small amount of gas generated in the target shell can also enter the airflow channel through the waterproof and breathable membrane 5 and be discharged to the external atmosphere, thereby maintaining the balance of the pressure difference between the interior and exterior of the target shell, so as to improve the service life and safety of the explosion-proof valve.
[0057] Specifically, when the gas pressure in the target shell is abnormally high, i.e., the gas pressure is rapidly increased and greater than the loading force of the spring 4, the gas can pass through the waterproof and breathable membrane 5 into the airflow channel and further compress the spring 4, the guide rod 2 moves forward to separate the first sealing ring 3 from the limiting step 13, and the explosion-proof valve automatically releases pressure, thereby ensuring the safety of the target shell. For example, the explosion-proof valve is configured to have a pressure relief range of 0.1 MPa to 0.2 MPa and a pressure relief range of 0.3 MPa to 0.8 MPa. For example, when the internal gas pressure of the target shell reaches 0.15 MPa, the guide rod 2 can move away from the first sealing ring 3 to release pressure, and reset to automatically close when the pressure is released to below 0.1 MPa. During the pressure relief process, if the gas pressure in the target shell continues to rise to 0.5 MPa, the explosion-proof valve can trigger the pressure relief function, which will be described in detail below.
[0058] The valve body 1 can be made of PBT material, which makes the valve body 1 have high rigidity, hardness and good processing performance, is beneficial to the forming of the first and second cavities 11 and 12, and ensures the heat resistance and thermal stability of the valve body 1, and meets the requirements of working conditions. The guide rod 2 and the spring 4 are made of stainless steel, wherein the length, elastic coefficient and compression amount of the spring 4 can be designed according to specific requirements. The first sealing ring 3 is preferably made of high-temperature-resistant fluororubber material to adapt to the sealing of electrolyte working conditions. The waterproof and breathable film 5 can be made of polytetrafluoroethylene material, which has good waterproof and breathable properties.
[0059] As shown in Figure 2 and Figure 3 , in some embodiments, the first cavity 11 is transversely arranged, and the second cavity 12 is obliquely arranged, and the two form a “7”-shaped air flow channel after being communicated. Compared with the “T”-shaped air flow channel of the existing explosion-proof valve, the valve body 1 is greatly reduced in size by transversely installing the guide rod 2 in the first cavity 11 and obliquely shortening the distance from the bottom surface to the top surface of the valve body 1, while meeting the functional requirements, thereby saving space.
[0060] As shown in Figure 3 , in some embodiments, the limiting step 13 includes an inclined matching surface 131, which can better contact the first sealing ring 3 to form a seal. The angle between the matching surface 131 and the horizontal plane is 110°-130°. If the angle is less than 110°, the contact area between the matching surface 131 and the first sealing ring 3 is small, and the sealing performance is difficult to maintain in a good state. If the angle is greater than 130°, the limiting effect of the matching surface 131 on the first sealing ring 3 decreases, which may cause the first sealing ring 3 to pass over the limiting step 13 and affect the sealing. In the present application, the angle between the matching surface 131 and the horizontal plane is preferably 115°-125°, for example, it can be 120°.
[0061] The first convex ring part 21 of the guide rod 2 is used to abut against the spring 4, and the other side, that is, the rear side, is also used to abut against the first sealing ring 3. However, during the pressure relief process, the forward movement of the guide rod 2 may cause the first sealing ring 3 to be offset or fall off, thereby affecting the sealing effect. Figure 4 As shown in Figure 4 , in some embodiments, the rear part of the guide rod 2 is further provided with a second convex ring part 22, and the second convex ring part 22 is spaced apart and arranged behind the first convex ring part 21, and the two form a groove structure together, which is used to install the first sealing ring 3 and enable the first sealing ring 3 to move, thereby improving the reliability of the sealing.
[0062] Further, the first and second convex ring portions 21 and 22 are respectively slidably arranged in the first and second cavity sections 111 and 112 of the first cavity 11, either of the first and second convex ring portions 21 and 22 can guide the movement of the guide rod 2 in a small range, so as to improve the stability of the pressure relief switch. In addition, the outer periphery of each of the first and second convex ring portions 21 and 22 is provided with a gas guide groove 6, which can ensure the smoothness of the gas flow channel while meeting the guiding function.
[0063] In some embodiments, the rivet column 7 can be fixed at the front end of the first cavity 11 by hot riveting, which is more conducive to the combination and fixation of the rivet column 7 and the valve body 1, and the front side of the rivet column 7 is a plane, so as to facilitate the hot riveting operation. In addition, the rivet column 7 is also used to assist the movement of the guide rod 2, so as to ensure the normal movement of the guide rod 2.
[0064] Referring to Figure 5 and Figure 6 As shown, the inner side of the rivet column 7 is circumferentially provided with a plurality of elastic membrane petals 8, which are substantially fan-shaped, and the number thereof can be 2-6, preferably 4.
[0065] In a natural state, each elastic membrane petal 8 is closed but has a gas permeable gap between adjacent elastic membrane petals 8. It can be understood that the closed elastic membrane petals 8 can substantially seal the first cavity 11, so as to prevent large-diameter impurities from entering and hindering the extension of the spring 4 or the movement of the guide rod 2, and ensure the normal use of the valve function. In addition, the design of the gas permeable gap can meet the gas permeation requirement of the explosion-proof valve, so that the gas in the target shell can be released without hindrance.
[0066] When the gas pressure in the target shell is greater than the loading force of the spring 4, that is, when the pressure is relieved, the guide rod 2 moves forward to force each elastic membrane petal 8 to open and form a gas permeable flow channel due to the large gas pressure in the gas flow channel. The opening and closing of the elastic membrane petals 8 are controlled by the guide rod 2, which can adaptively control the size of the gas permeable flow channel according to the gas flow. Specifically, the greater the gas pressure, the greater the distance of the forward movement of the guide rod 2, and the greater the opening of the elastic membrane petals 8, so as to realize the function of rapid exhaust and pressure relief. Conversely, the size is reduced, which will not be described herein.
[0067] Further, as shown in Figure 4 , the front end of the guide rod 2 is hollow (not shown), or the front end of the guide rod 2 is provided with a gas guide hole 23 extending to the middle of the rod body. The above two ways can guide more gas to flow from the first cavity 11 to the outside of the elastic membrane petals 8, and further strengthen the function of exhaust and pressure relief.
[0068] Referring to Figure 1 and Figure 2As shown in the drawings, in some embodiments, a second sealing ring 9 is arranged between the valve body 1 and the target shell, which can also be made of high-temperature-resistant fluororubber material, and is located at the outer periphery of the waterproof and breathable film 5, for improving the sealing between the valve body 1 and the target shell, preventing external water vapor from entering the interior of the target shell and affecting the service life. In the present application, the bottom surface of the valve body 1 is also provided with a groove-shaped structure, and the second sealing ring 9 is installed in the groove, and by welding the valve body 1 and the target shell, the second sealing ring 9 can be compressed to form a seal.
[0069] As shown in the drawings, Figure 2 In some embodiments, the bottom surface of the valve body 1 is also provided with a welding structure 10. Specifically, the welding structure 10 includes a boss 101 arranged at the outer edge of the bottom surface of the valve body 1, and a tapered protrusion 102 arranged at the lower end of the boss 101. In the present application, the bosses 101 are distributed circumferentially and can be fixed to the target shell by ultrasonic welding through the tapered protrusions 102 at the lower end (see Figure 7 ). Under normal conditions, the gas generated in the target shell is discharged through the airflow channel in the valve body 1, and when the internal pressure of the target shell is abnormally high (for example, the pressure rises to 0.5 MPa at a very high speed), the airflow channel alone cannot guarantee safety, at this time, the huge pressure can cause the boss 101 to be cracked at the welding position of the target shell, causing the gas in the target shell to be rapidly discharged to the outside atmosphere, avoiding the occurrence of explosion hazards, and playing a function of explosion relief.
[0070] The utility model also discloses a battery pack (not shown), including above-mentioned explosion -proof valve, wherein the valve body 1 of explosion -proof valve is welded with the battery shell of battery pack, and makes second chamber 12 with the inside of battery shell keeps communication, like this improves the safety and reliability of battery pack.
[0071] Although the embodiments of the utility model have been shown and described above, it should be understood that the above-mentioned embodiments are exemplary and cannot be understood as limiting the utility model, and the person skilled in the art can change, modify, replace and transform the above-mentioned embodiments within the scope of the utility model without departing from the principles and purposes of the utility model, and all these changes should belong to the protection scope of the utility model claim.
Claims
1. An explosion relief valve installed on a target housing, characterized by, The valve body (1) has a first cavity (11) extending inward from the side wall and a second cavity (12) extending inward from the bottom surface, wherein the first and second cavities (12) are connected, and the first cavity (11) is provided with a limiting step (13) in front of the connection; A guide rod (2) is movably arranged in the first cavity (11), and the guide rod (2) is provided with a first sealing ring (3); A spring (4) is arranged in the first cavity (11), and the spring (4) is used to apply a backward loading force to the guide rod (2); A waterproof and breathable membrane (5) is arranged below the second cavity (12); In a natural state, the guide rod (2) tightly presses the first sealing ring (3) against the limiting step (13) to form a seal, and when the air pressure in the target shell is greater than the loading force of the spring (4), the guide rod (2) moves forward to cause the first sealing ring (3) to separate from the limiting step (13) to release pressure. The first cavity (11) is arranged transversely, and the second cavity (12) is arranged obliquely, and the two form a "7"-shaped air flow channel after being connected.
2. The explosion relief valve of claim 1, wherein The limiting step (13) includes an inclined matching surface (131), and the angle between the matching surface (131) and the horizontal plane is 110°-130°.
3. The explosion relief valve of claim 1, wherein, The rear part of the guide rod (2) is provided with spaced first and second convex ring parts (21, 22); 4. The explosion relief valve of claim 1, wherein, The spring (4) is located in front of the first convex ring part (21), and the first sealing ring (3) is located between the first and second convex ring parts (21, 22). The front end of the first cavity (11) is provided with a hollow rivet column (7), which is used to fix the spring (4) and assist the movement of the guide rod (2).
5. The explosion relief valve of claim 1, wherein The inner side of the rivet column (7) is circumferentially uniformly distributed with a plurality of elastic membrane petals (8); 6. The explosion relief valve of claim 5, wherein, In a natural state, each elastic membrane petal (8) is closed but has a breathable gap between adjacent ones, and when the air pressure in the target shell is greater than the loading force of the spring (4), the guide rod (2) moves forward to force each elastic membrane petal (8) to open to form a breathable flow channel. A second sealing ring (9) is arranged between the valve body (1) and the target shell, and the second sealing ring (9) is located outside the waterproof and breathable membrane (5).
7. The explosion relief valve of claim 1, wherein The bottom surface of the valve body (1) is also provided with a welding structure (10); 8. The explosion relief valve of claim 1, wherein, The welding structure (10) includes a boss (101) arranged at the outer edge of the bottom surface of the valve body (1), and a tapered protrusion (102) arranged at the lower end of the boss (101). The explosion-proof valve is configured to have a pressure relief range of 0.1 MPa-0.2 MPa and an explosion relief range of 0.3 MPa-0.8 MPa.
9. The explosion relief valve of claim 1, wherein, The explosion-proof valve comprises any one of claims 1-9.
10. A battery pack, characterized by,