A battery pack explosion-proof vent valve
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- Filing Date
- 2025-09-01
- Publication Date
- 2026-08-11
AI Technical Summary
然而，此类结构的防爆阀存在响应速度较慢的问题，亟需改进
[0007]上述方案通过由透气材料制成的第一膜片覆盖第一通孔，在电池包正常工作且内外产生压力差时，电池包内部气体可缓慢持续地从导流孔经第一通孔、第一膜片和阀孔后从泄压孔排出，或者外界气体缓慢持续地从泄压孔经阀孔、第一膜片和第一通孔后从导流孔流入，实现气压平衡，此过程无需刺破第二膜片，第二膜片不参与透气，有效避免了正常工况下防爆透气阀的非预期开启和失效；
Smart Images
Figure CN224625809U_ABST
Abstract
Description
Technical Field
[0001] This utility model relates to the technical field of explosion-proof vent valves, and more specifically to an explosion-proof vent valve for a battery pack. Background Technology
[0002] As one of the three core components of new energy vehicles, ensuring the safety of the battery pack has always been a key research focus in the industry. Under normal operating conditions, the battery pack is in a sealed, encapsulated state.
[0003] Under normal operating conditions, the gas pressure inside the battery pack changes with variations in temperature, air pressure, and altitude. To ensure proper battery pack operation, a vent valve is typically added to its casing to balance the internal and external gas pressure. Due to the special nature of battery packs, the vent valve must be both breathable and waterproof.
[0004] When a battery cell experiences thermal runaway (caused by internal short circuits, external impacts, or high temperatures), the cell temperature can rise rapidly, releasing a large amount of gas, which can then affect surrounding cells, creating a chain reaction of thermal propagation. To ensure battery pack safety, explosion-proof valves are typically added to the battery pack casing. When the gas inside the battery pack expands and the pressure rises, the explosion-proof valve automatically opens to release pressure, effectively preventing thermal propagation and battery pack explosion. Existing explosion-proof valves are primarily metal structures, including a valve body, valve core, and spring. When the gas inside the battery pack expands to a value greater than a preset threshold, the gas pushes the valve core to overcome the spring force and open, allowing the gas inside the battery pack to flow out through the valve body to release pressure. However, this type of explosion-proof valve has a slow response time and urgently needs improvement. Utility Model Content
[0005] The purpose of this invention is to provide a battery pack explosion-proof vent valve that can eliminate the internal and external pressure difference generated during normal operation of the battery pack, and effectively prevent the thermal spread and explosion of the battery pack.
[0006] To address the aforementioned problems, this utility model provides a battery pack explosion-proof vent valve, comprising a first diaphragm made of a breathable material, a second diaphragm made of an elastic non-breathable material, and a valve body with a valve hole inside. One end of the valve hole is provided with a valve cover, which has a pressure relief hole connecting the valve hole to the outside. The inner peripheral wall of the other end of the valve hole has a raised, annular first stepped platform. A valve seat is provided on the side of the first stepped platform facing away from the valve cover. The valve seat has an independent guide hole and an explosion-proof hole. The first stepped platform has a first through hole connecting the guide hole and the valve hole. The end of the explosion-proof hole near the first stepped platform connects to the valve hole through the inner hole of the first stepped platform. The inner peripheral wall of the end of the explosion-proof hole away from the first stepped platform has a raised second stepped platform, which has a second through hole connecting the explosion-proof hole to the outside. The first diaphragm is annular and installed on the first stepped platform to cover the first through hole. The second diaphragm is installed on the second stepped platform to cover the second through hole. The valve cover has a needle pointing towards the second diaphragm.
[0007] The above solution covers the first through hole with a first diaphragm made of breathable material. When the battery pack is working normally and a pressure difference is generated inside and outside, the gas inside the battery pack can be slowly and continuously discharged from the guide hole through the first through hole, the first diaphragm and the valve hole and then through the pressure relief hole. Alternatively, the gas outside can be slowly and continuously discharged from the pressure relief hole through the valve hole, the first diaphragm and the first through hole and then through the guide hole, thus achieving air pressure balance. This process does not require puncturing the second diaphragm, and the second diaphragm does not participate in air permeation, effectively avoiding the unexpected opening and failure of the explosion-proof vent valve under normal working conditions. When the battery pack experiences thermal runaway and the internal gas pressure rises sharply and abnormally, the high-pressure gas pushes the second diaphragm to deform elastically through the second through hole and punctures it by contacting the needle of the valve cover. At this time, the gas inside the battery pack can be quickly discharged from the second through hole through the explosion-proof hole, the inner hole of the stepped platform and the valve hole, and then through the pressure relief hole to achieve rapid pressure relief and prevent the battery pack from thermal spread and explosion. Furthermore, since the first diaphragm and the second diaphragm are respectively disposed on the first step platform and the second step platform, this layered design allows the axial length of the valve body to be made smaller, thereby reducing the overall size and reducing the exposed space after the explosion-proof vent valve is installed on the battery pack.
[0008] In an improved embodiment, the valve seat includes an outer cylinder and an inner cylinder, both of which are connected to a first stepped platform. The inner cylinder is located inside the outer cylinder, and the outer and inner cylinders are coaxially arranged relative to the valve orifice. A flow guide hole is formed between the outer peripheral wall of the inner cylinder and the inner peripheral wall of the outer cylinder, and an explosion-proof hole is formed on the inner side of the inner cylinder. This makes the valve seat structure compact and easy to process. The flow guide hole with an annular radial cross-section has a large flow area, which can ensure that the gas enters the first through hole uniformly. The explosion-proof hole is located on the inner side of the inner cylinder, ensuring that the second diaphragm has sufficient elastic deformation space.
[0009] In an improved embodiment, the first through holes are multiple and distributed circumferentially along the first stepped platform, thereby ensuring that the guide holes can enter the valve holes more uniformly and stably through the multiple first through holes.
[0010] In an improved version, the outer cylinder has external threads on its outer side to facilitate installation.
[0011] In an improved embodiment, a rubber sealing ring is fitted onto the outer side of the outer cylinder. Since the outer cylinder is used to install into the battery pack, the presence of the rubber sealing ring can provide a sealing effect for the installation of the outer cylinder, and at the same time, it can also achieve an anti-loosening function.
[0012] In an improved embodiment, a first retaining ring and a second retaining ring are also included. The first diaphragm is located on the side of the first stepped platform facing the valve cover. The first retaining ring is connected to the valve hole by ultrasonic welding and abuts against the side of the first diaphragm facing the valve cover. The second diaphragm is located on the side of the second stepped platform facing the valve cover. The second retaining ring is connected to the explosion-proof hole by ultrasonic welding and abuts against the side of the second diaphragm facing the valve cover. Thus, the first diaphragm is secured by the first retaining ring, and the second diaphragm is secured by the second retaining ring.
[0013] In an improved embodiment, the inner circumferential wall of one end of the valve cover corresponding to the valve hole is provided with an annular groove, and the outer edge of the valve cover is provided with a hook that engages with the groove. Thus, the valve cover is assembled relative to the valve hole through the engagement of the hook and the groove, which is simple and convenient to operate.
[0014] In an improved embodiment, the pressure relief holes on the valve cover are multiple and spaced apart circumferentially, and the flow area of the pressure relief holes gradually increases in the direction away from the valve hole, thereby ensuring that the gas in the valve hole can be uniformly discharged to the outside through the pressure relief holes of the valve cover.
[0015] In an improved embodiment, a filter screen is provided on the side of the valve cover facing the valve hole. The filter screen can effectively reduce the probability of impurities such as gravel and insects entering the valve hole through the pressure relief hole, thereby achieving protection.
[0016] In an improved design, the valve cover has multiple triangular puncture needles, which increases the puncture area on the second diaphragm and enables rapid pressure relief. Attached Figure Description
[0017] Figure 1 A schematic diagram of the valve body of an explosion-proof vent valve for a battery pack; Figure 2 A schematic diagram of the valve seat for an explosion-proof vent valve for a battery pack; Figure 3 This is a schematic diagram of a battery pack explosion-proof vent valve with the valve cover removed. Figure 4 For a type of explosion-proof vent valve for battery packs Figure 3 A schematic diagram with the first diaphragm and the first retaining ring removed; Figure 5 This is a top view schematic diagram of an explosion-proof vent valve for a battery pack; Figure 6 For along Figure 5 Schematic diagram of the cross section line AA in the middle.
[0018] Explanation of reference numerals in the attached figures. 1. Valve body; 11. Valve hole; 111. Slot; 12. First stepped platform; 121. First through hole; 13. First retaining ring; 2. First diaphragm; 3. Second diaphragm; 4. Valve cover; 41. Pressure relief hole; 42. Needle; 43. Hook; 44. Filter screen; 5. Valve seat; 501. Outer cylinder; 502. Inner cylinder; 51. Flow guide hole; 52. Explosion-proof hole; 53. Second stepped platform; 531. Second through hole; 54. Second retaining ring; 55. Rubber sealing ring. Detailed Implementation
[0019] It should be understood by those skilled in the art that the following embodiments are merely illustrative of the technical principles of the embodiments of this application and are not intended to limit the scope of protection of the embodiments of this application. Those skilled in the art can make adjustments as needed to adapt to specific application scenarios.
[0020] In the following description of the embodiments, it should be noted that, unless otherwise explicitly specified and limited, the terms "connected" and "linked" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral connection; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium. Those skilled in the art can understand the specific meaning of the above terms in the embodiments of this application based on the specific circumstances.
[0021] In the embodiments of this application, unless otherwise expressly specified and limited, "above" or "below" the second feature can mean that the first feature is in direct contact with the second feature, or that the first feature is in indirect contact with the second feature through an intermediate medium. Furthermore, "above," "on top of," and "over" the second feature can mean that the first feature is directly above or diagonally above the second feature, or simply that the first feature is at a higher horizontal level than the second feature. "Below," "below," and "under" the second feature can mean that the first feature is directly below or diagonally below the second feature, or simply that the first feature is at a lower horizontal level than the second feature.
[0022] The present application will now be described in further detail with reference to the accompanying drawings and specific embodiments.
[0023] Please see Figures 1-6 This utility model provides a battery pack explosion-proof vent valve, comprising a first diaphragm 2 made of a breathable material, a second diaphragm 3 made of an elastic non-breathable material, and a valve body 1 with a valve hole 11 inside. One end of the valve hole 11 is provided with a valve cover 4, which has a pressure relief hole 41 connecting the valve hole 11 to the outside. The inner peripheral wall of the other end of the valve hole 11 is provided with a first stepped platform 12 protruding in an annular shape. A valve seat 5 is provided on the side of the first stepped platform 12 facing away from the valve cover 4. The valve seat 5 has independent guide holes 51 and explosion-proof holes 52. The first stepped platform 12 has a connecting guide hole 51 and valve body 1. The first through hole 121 of hole 11; the explosion-proof hole 52 near the first stepped platform 12 is connected to the valve hole 11 through the inner hole of the first stepped platform 12; the inner peripheral wall of the explosion-proof hole 52 away from the first stepped platform 12 is provided with a raised second stepped platform 53; the second stepped platform 53 is provided with a second through hole 531 connecting the explosion-proof hole 52 and the outside; the first diaphragm 2 is annular and installed on the first stepped platform 12 to cover the first through hole 121; the second diaphragm 3 is installed on the second stepped platform 53 to cover the second through hole 531; the valve cover 4 is provided with a needle 42 facing the second diaphragm 3.
[0024] The above solution covers the first through hole 121 with a first diaphragm 2 made of breathable material. When the battery pack is working normally and a pressure difference is generated inside and outside, the gas inside the battery pack can be slowly and continuously discharged from the guide hole 51 through the first through hole 121, the first diaphragm 2 and the valve hole 11 and then discharged from the pressure relief hole 41. Alternatively, the external gas can be slowly and continuously discharged from the pressure relief hole 41 through the valve hole 11, the first diaphragm 2 and the first through hole 121 and then flow into the guide hole 51, thus achieving air pressure balance. This process does not require puncturing the second diaphragm 3. The second diaphragm 3 does not participate in air permeation, effectively avoiding the unexpected opening and failure of the explosion-proof vent valve under normal working conditions. When the battery pack experiences thermal runaway and the internal gas pressure rises sharply and abnormally, the high-pressure gas pushes the second diaphragm 3 to deform elastically through the second through hole 531 and punctures it by contacting the needle 42 of the valve cover 4. At this time, the gas inside the battery pack can be quickly discharged from the second through hole 531 through the explosion-proof hole 52, the inner hole of the stepped platform and the valve hole 11 and then through the pressure relief hole 41, so as to achieve rapid pressure relief and prevent the battery pack from thermal spread and explosion. Furthermore, since the first diaphragm 2 and the second diaphragm 3 are respectively disposed on the first step platform 12 and the second step platform 53, this layered design allows the axial length of the valve body 1 to be smaller, thereby reducing the overall size and reducing the exposed space after the explosion-proof vent valve is installed on the battery pack.
[0025] by Figure 4Based on the reference, valve hole 11 is opened vertically, valve cover 4 is connected to the upper end of valve hole 11, and valve seat 5 is connected to the lower part of valve body 1. In this embodiment, valve seat 5 includes an outer cylinder 501 and an inner cylinder 502. The upper ends of the outer cylinder 501 and the upper ends of the inner cylinder 502 are both connected to the first stepped platform 12. The inner cylinder 502 is located inside the outer cylinder 501 and the outer cylinder 501 and the inner cylinder 502 are arranged coaxially relative to valve hole 11. The outer peripheral wall of the inner cylinder 502 and the inner peripheral wall of the outer cylinder 501 form a guide hole 51. An explosion-proof hole 52 is formed on the inner side of the inner cylinder 502, so that the valve seat 5 has a compact structure and is easy to process. The guide hole 51 with an annular radial cross section has a large flow area, which can ensure that the gas enters the first through hole 121 uniformly. The explosion-proof hole 52 is located on the inner side of the inner cylinder 502, ensuring that the second diaphragm 3 has sufficient elastic deformation space.
[0026] In this embodiment, there are multiple first through holes 121 and they are distributed circumferentially along the first stepped platform 12, thereby ensuring that the guide hole 51 can enter the valve hole 11 more evenly and stably through the multiple first through holes 121.
[0027] In this embodiment, the outer cylinder 501 has external threads on its outer side to facilitate installation. Furthermore, a rubber sealing ring 55 is fitted onto the outer side of the outer cylinder 501. Since the outer cylinder 501 is used to install into the battery pack, the presence of the rubber sealing ring 55 can provide a sealing effect for the installation of the outer cylinder 501, and also achieve an anti-loosening function.
[0028] In this embodiment, a first retaining ring 13 and a second retaining ring 54 are also included. The first diaphragm 2 is located on the side of the first stepped platform 12 facing the valve cover 4. The first retaining ring 13 is connected to the valve hole 11 by ultrasonic welding and abuts against the side of the first diaphragm 2 facing the valve cover 4. The second diaphragm 3 is located on the side of the second stepped platform 53 facing the valve cover 4. The second retaining ring 54 is connected to the explosion-proof hole 52 by ultrasonic welding and abuts against the side of the second diaphragm 3 facing the valve cover 4. Thus, the first retaining ring 13 is used to fasten the first diaphragm 2, and the second retaining ring 54 is used to fasten the second diaphragm 3.
[0029] In this embodiment, the inner circumferential wall of one end of the valve hole 11 corresponding to the valve cover 4 is provided with an annular groove 111, and the outer edge of the valve cover 4 is provided with a hook 43 that engages with the groove 111. Thus, the valve cover 4 is assembled relative to the valve hole 11 through the engaging fit between the hook 43 and the groove 111, making the operation simple and convenient. Of course, the valve cover 4 can also be directly press-fitted to the valve hole 11 using an interference fit; the specific assembly method is not limited in this design.
[0030] As an optimization of the valve cover 4, the valve cover 4 has multiple pressure relief holes 41 distributed circumferentially, and the flow area of the pressure relief holes 41 gradually increases in the direction away from the valve hole 11, thereby ensuring that the gas in the valve hole 11 can be uniformly discharged to the outside through the pressure relief holes 41 of the valve cover 4. In this embodiment, the pressure relief holes 41 are elongated and the hole width gradually increases from bottom to top to achieve the structure that "the flow area of the pressure relief holes 41 gradually increases in the direction away from the valve hole 11".
[0031] As another optimization of this embodiment, a filter screen 44 is provided on the side of the valve cover 4 facing the valve hole 11. The filter screen 44 can effectively reduce the probability of impurities such as gravel and insects entering the valve hole 11 through the pressure relief hole 41, thereby achieving protection.
[0032] In this embodiment, the valve cover 4 has multiple needles 42 arranged in a triangular shape, which increases the puncture area of the second diaphragm 3 and enables rapid pressure relief.
[0033] It should be noted that in the description of this application, the terms "inner" and "outer," etc., indicating directions or positional relationships, are based on the directions or positional relationships shown in the accompanying drawings. This is only for the convenience of description and does not indicate or imply that the device or component must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, it should not be construed as a limitation of this application. All directional indications (such as up, down, left, right, front, back, inner, and outer) are only used to explain the relative positional relationships and movement between components in a specific posture. If the specific posture changes, the directional indication will also change accordingly.
[0034] In the description of this application, the references to terms such as "an embodiment," "some embodiments," "in this embodiment," "specific example," or "some examples," etc., refer to specific features, structures, materials, or characteristics described in connection with that embodiment or example, which are included in at least one embodiment or example of this application. In this specification, the illustrative expressions of the above terms do not necessarily refer to the same embodiment or example. Furthermore, the specific features, structures, materials, or characteristics described may be combined in a suitable manner in any one or more embodiments or examples. Moreover, without contradiction, those skilled in the art can combine and integrate the different embodiments or examples described in this specification, as well as the features of different embodiments or examples.
[0035] The above description is merely a specific embodiment of this application, but the scope of protection of this application is not limited thereto. Any variations or substitutions that can be easily conceived by those skilled in the art within the technical scope disclosed in this application should be included within the scope of protection of this application. Therefore, the scope of protection of this application should be determined by the scope of the claims.
Claims
1. A battery pack explosion-proof breather valve, characterized in that, The device includes a first diaphragm (2) made of breathable material, a second diaphragm (3) made of elastic non-breathable material, and a valve body (1) with a valve hole (11). One end of the valve hole (11) is provided with a valve cover (4), which has a pressure relief hole (41) connecting the valve hole (11) and the outside. The inner peripheral wall of the other end of the valve hole (11) is provided with a first stepped platform (12) that protrudes in an annular shape. A valve seat (5) is provided on the side of the first stepped platform (12) facing away from the valve cover (4). The valve seat (5) has independent guide holes (51) and explosion-proof holes (52). The first stepped platform (12) has a first through hole (121) connecting the guide holes (51) and the valve hole (11). The explosion-proof hole (52) is connected to the valve hole (11) through the inner hole of the first step platform (12) at one end near the first step platform (12). The inner peripheral wall of the explosion-proof hole (52) away from the first step platform (12) is provided with a raised second step platform (53). The second step platform (53) is provided with a second through hole (531) connecting the explosion-proof hole (52) and the outside. The first diaphragm (2) is annular and installed on the first step platform (12) to cover the first through hole (121). The second diaphragm (3) is installed on the second step platform (53) to cover the second through hole (531). The valve cover (4) is provided with a needle (42) facing the second diaphragm (3).
2. The battery pack explosion venting breather valve of claim 1, wherein, The valve seat (5) includes an outer cylinder (501) and an inner cylinder (502). Both the outer cylinder (501) and the inner cylinder (502) are connected to the first stepped platform (12). The inner cylinder (502) is located inside the outer cylinder (501), and the outer cylinder (501) and the inner cylinder (502) are coaxially arranged relative to the valve hole (11). The outer peripheral wall of the inner cylinder (502) and the inner peripheral wall of the outer cylinder (501) form a flow guide hole (51). An explosion-proof hole (52) is formed on the inner side of the inner cylinder (502).
3. The battery pack explosion-proof vent valve according to claim 2, characterized in that, The first through hole (121) is multiple and is distributed circumferentially along the first step (12).
4. The battery pack explosion-proof vent valve according to claim 2, characterized in that, The outer cylinder (501) has external threads on its outer side.
5. The battery pack explosion-proof vent valve according to claim 4, characterized in that, A rubber sealing ring (55) is fitted onto the outer side of the outer cylinder (501).
6. The battery pack explosion-proof vent valve according to any one of claims 1-3, characterized in that, It also includes a first retaining ring (13) and a second retaining ring (54). The first diaphragm (2) is located on the side of the first step (12) facing the valve cover (4). The first retaining ring (13) is connected to the valve hole (11) by ultrasonic welding and abuts against the side of the first diaphragm (2) facing the valve cover (4). The second diaphragm (3) is located on the side of the second step (53) facing the valve cover (4). The second retaining ring (54) is connected to the explosion-proof hole (52) by ultrasonic welding and abuts against the side of the second diaphragm (3) facing the valve cover (4).
7. The battery pack explosion-proof vent valve according to claim 1, characterized in that, The valve hole (11) has an annular groove (111) on the inner circumferential wall of one end of the valve cover (4), and the outer edge of the valve cover (4) has a hook (43) that engages with the groove (111).
8. The battery pack explosion-proof vent valve according to claim 1, characterized in that, The valve cover (4) has multiple pressure relief holes (41) that are spaced apart circumferentially, and the flow area of the pressure relief holes (41) gradually increases in the direction away from the valve hole (11).
9. The battery pack explosion-proof vent valve according to claim 1 or 7, characterized in that, A filter screen (44) is provided on the side of the valve cover (4) facing the valve hole (11).
10. The battery pack explosion-proof vent valve according to claim 1, characterized in that, The valve cover (4) has multiple needles (42) arranged in a triangular shape.