Battery cover plate, battery, battery pack and vehicle
By designing the combined structure of the first and second explosion-proof valves on the battery cover, the problem of liquid leakage caused by the early failure of the explosion-proof valve is solved, and a longer service life and higher safety are achieved.
Patent Information
- Application Number
- CN202420488072.4
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- Filing Date
- 2024-03-12
- Publication Date
- 2025-03-04
- Estimated Expiration
- 2034-03-12
AI Technical Summary
The explosion-proof valves of existing battery covers are prone to fail in advance due to attenuation of pressure relief capacity in scenarios such as charging and discharging, resulting in an increase in the risk of liquid leakage.
A battery cover plate is designed, including a first explosion-proof valve and a second explosion-proof valve arranged in sequence on the inner and outer sides. The first explosion-proof valve is opened during pressure relief, the second explosion-proof valve is arranged outside the first explosion-proof valve, at least the first explosion-proof part is sealed to provide deformation space to ensure the smooth opening of the first explosion-proof valve, and reduce the risk of liquid leakage through the sealing and explosion-proof function of the second explosion-proof valve.
It effectively extends the service life of the explosion-proof valve, reduces the risk of liquid leakage, ensures that the battery can effectively discharge internal pressure when needed, and improves the sealing and safety of the battery.
Smart Images
Figure CN222562803U_ABST
Abstract
Description
Technical Field
[0001] The present application relates to the field of battery technology, and in particular to a battery cover, a battery, a battery pack and a vehicle. Background Art
[0002] The battery cover is usually equipped with an explosion-proof valve, which can be opened under a certain air pressure to release the gas inside the battery, ensuring that the internal pressure of the battery can be released as soon as possible in the event of thermal runaway, thus avoiding a violent explosion of the battery. However, in actual applications, the pressure relief capacity of the explosion-proof valve will decay to a certain extent as the battery is used in charging, discharging and other scenarios, leading to premature failure and the risk of leakage. Utility Model Content
[0003] The present application aims to solve at least one of the technical problems existing in the prior art. To this end, the present application proposes a battery cover to solve the risk of battery leakage caused by premature failure of the explosion-proof valve. The present application also proposes a battery having the battery cover, as well as a battery pack and a vehicle having the battery.
[0004] The battery cover of the first embodiment of the present application includes a cover body, a first explosion-proof valve and a second explosion-proof valve. The cover body has an inner wall and an outer wall relative to each other, and the cover body is provided with an explosion-proof hole that penetrates the inner wall and the outer wall; the first explosion-proof valve covers the explosion-proof hole, the first explosion-proof valve includes a first explosion-proof portion corresponding to the explosion-proof hole, and a first connecting portion arranged around the first explosion-proof portion, the first connecting portion is sealed and connected to the cover body, and the first explosion-proof valve is configured to open the first explosion-proof portion when the pressure is released; the second explosion-proof valve is arranged on the outside of the first explosion-proof valve, including a second explosion-proof portion corresponding to the explosion-proof hole, and a second connecting portion arranged around the second explosion-proof portion, there is a gap between the second explosion-proof portion and the first explosion-proof portion, the second connecting portion is sealed and connected to the first connecting portion or the cover body, and the second explosion-proof valve at least covers the first explosion-proof portion.
[0005] The battery cover according to the first embodiment of the present application has at least the following beneficial effects: when applied to a battery, the gap between the first explosion-proof part and the second explosion-proof part provides a deformation space for the opening of the first explosion-proof part, so that the first explosion-proof valve can be opened smoothly. The first explosion-proof valve can withstand the gas impact and corrosion inside the battery, and the second explosion-proof valve effectively guarantees the pressure relief capacity because it is blocked by the first explosion-proof valve on the inside. Therefore, when the first explosion-proof valve fails prematurely, the second explosion-proof valve can work normally, play a sealing role and explosion-proof role, effectively reduce the risk of leakage, and ensure a certain valve opening pressure to ensure that the pressure inside the battery can be effectively discharged when needed, effectively improving the service life of the battery.
[0006] In some embodiments of the battery cover of the present application, a groove is provided on the outer side of the first connecting portion, the groove is recessed inward, and the second connecting portion is located in the groove and is sealed and connected to the first connecting portion.
[0007] In some embodiments of the battery cover of the present application, the groove includes a bottom wall and a side wall, the bottom wall faces outward, the side wall is arranged on the outer edge of the bottom wall and extends outward from the bottom wall, and the side wall surrounds the outer periphery of the second connecting portion.
[0008] In some embodiments of the battery cover of the present application, the second connecting portion includes a connecting section and an extension section, the connecting section is located on the inner side of the second explosion-proof portion and connected to the first connecting portion, and the extension section is connected between the second explosion-proof portion and the connecting section.
[0009] In the battery cover of some embodiments of the present application, the thickness of the extension section gradually increases from an end connected to the second explosion-proof portion to an end connected to the connecting section.
[0010] In the battery cover of some embodiments of the present application, the valve opening pressure of the first explosion-proof valve is greater than or equal to the valve opening pressure of the second explosion-proof valve.
[0011] In the battery cover of some embodiments of the present application, the valve opening pressure of the first explosion-proof valve is configured in the range of 0.4 MPa to 0.7 MPa, and / or the valve opening pressure of the second explosion-proof valve is configured in the range of 0.6 MPa to 1.0 MPa.
[0012] In the battery cover of some embodiments of the present application, a first notch is provided on the outer side of the first explosion-proof part, and the first notch is recessed toward the inside, or a first notch is provided on the inner side of the first explosion-proof part, and the first notch is recessed toward the outside; a second notch is provided on the outer side of the second explosion-proof part, and the second notch is recessed toward the inside, or a second notch is provided on the inner side of the second explosion-proof part, and the second notch is recessed toward the outside.
[0013] In the battery cover of some embodiments of the present application, the thickness of the first explosion-proof part is D1, and the depth of the first notch is H1, wherein D1>H1; the thickness of the second explosion-proof part is D2, and the depth of the second notch is H2, wherein D2>H2, and D2-H2≥D1-H1.
[0014] In the battery cover of some embodiments of the present application, in the first explosion-proof valve: D1-H1≥45μm.
[0015] In some embodiments of the battery cover of the present application, the explosion-proof hole includes a connected through hole and a step hole, the step hole is located on the inner side of the through hole, the through hole passes through the outer wall of the cover body, the step hole passes through the inner wall of the cover body, and the first explosion-proof valve is arranged in the step hole and covers the through hole.
[0016] In some embodiments of the battery cover of the present application, the battery cover also includes a protective member, which is arranged on the outside of the second explosion-proof valve and at least covers the second explosion-proof part, and the protective member is connected to the cover body.
[0017] The battery of the second aspect embodiment of the present application includes a battery cover of any embodiment of the first aspect. When the first explosion-proof valve fails prematurely, the second explosion-proof valve can play an explosion-proof and sealing role, thereby reducing the risk of leakage and ensuring a certain valve opening pressure to ensure that the pressure inside the battery can be effectively discharged when needed to prevent safety accidents such as battery explosion, thereby effectively improving the sealing and safety of the battery.
[0018] The battery pack of the third aspect embodiment of the present application includes multiple batteries of any one of the second aspect embodiments described above. Each battery is provided with the above-mentioned battery cover to effectively improve the sealing and safety of the battery, thereby effectively avoiding leakage contamination between the batteries inside the battery pack, thereby improving the safety of the battery pack.
[0019] The vehicle of the fourth embodiment of the present application comprises a plurality of batteries as described in any one of the embodiments of the second aspect. Each battery can effectively improve the sealing and safety by providing the battery cover, thereby improving the safety of the vehicle.
[0020] Additional aspects and advantages of the present application will be given in part in the description below, and in part will become apparent from the description below, or will be learned through the practice of the present application. BRIEF DESCRIPTION OF THE DRAWINGS
[0021] Figure 1 This is a schematic structural diagram of a battery cover according to an embodiment of the present application;
[0022] Figure 2 for Figure 1 An exploded view of the battery cover is shown;
[0023] Figure 3 A schematic cross-sectional view of a battery cover plate along the axial direction of an explosion-proof hole according to an embodiment;
[0024] Figure 4 for Figure 3 A local enlarged schematic diagram of point A in FIG.
[0025] Figure 5This is a schematic diagram of the structure of a second explosion-proof valve in an embodiment;
[0026] Figure 6 for Figure 5 A schematic cross-sectional view of the second explosion-proof valve along the axial direction of the explosion-proof hole is shown;
[0027] Figure 7 for Figure 6 A local enlarged schematic diagram of point B in FIG.
[0028] Figure 8 for Figure 5 A schematic structural diagram of the second explosion-proof valve from another perspective is shown;
[0029] Fig. 9 This is a schematic structural diagram of a first explosion-proof valve in an embodiment;
[0030] Fig.10 for Fig. 9 A schematic cross-sectional view of the first explosion-proof valve along the axial direction of the explosion-proof hole is shown;
[0031] Fig.11 for Fig.10 A local enlarged schematic diagram of point C in FIG.
[0032] Fig.12 is a schematic cross-sectional view of the cover plate body along the axial direction of the explosion-proof hole in one embodiment;
[0033] Fig.13 for Fig.12 A local enlarged schematic diagram of point D in the figure.
[0034] Reference numerals:
[0035] Battery cover 10;
[0036] Cover plate body 100; inner wall 101; outer wall 102; explosion-proof hole 110; through hole 111; step hole 112; step portion 113; pole hole 120;
[0037] First explosion-proof valve 200; first explosion-proof portion 210; first connecting portion 220; groove 221; bottom wall 222; side wall 223; first notch 230;
[0038] Second explosion-proof valve 300; second explosion-proof portion 310; second connecting portion 320; connecting section 321; extending section 322; gap 330; second notch 340;
[0039] Protective member 400 ; pole 500 ; riveting block 600 ; sealing ring 700 ; lower plastic 800 ; via hole 810 ; exhaust hole 820 ; upper plastic 900 . DETAILED DESCRIPTION
[0040] The following will clearly and completely describe the concept of the present application and the technical effects produced in combination with the embodiments, so as to fully understand the purpose, features and effects of the present application. Obviously, the described embodiments are only part of the embodiments of the present application, not all of them. Based on the embodiments of the present application, other embodiments obtained by those skilled in the art without creative work are all within the scope of protection of the present application.
[0041] In the description of the embodiments of the present application, if orientation descriptions are involved, the orientations or positional relationships indicated by "up", "down", "front", "back", "left", "right", etc. are based on the orientations or positional relationships shown in the accompanying drawings. They are only for the convenience of describing the present application and simplifying the description, and do not indicate or imply that the device or device referred to must have a specific orientation, be constructed and operated in a specific orientation. Therefore, they cannot be understood as limitations on the present application.
[0042] In the description of the embodiments of the present application, if a feature is referred to as being “set,” “fixed,” “connected,” or “installed” on another feature, it may be directly set, fixed, or connected to another feature, or it may be indirectly set, fixed, connected, or installed on another feature. In the description of the embodiments of the present application, if “several” is involved, it means more than one; if “multiple” is involved, it means more than two; if “greater than,” “less than,” or “exceeds” is involved, it should be understood as not including the number itself; if “above,” “below,” or “within” is involved, it should be understood as including the number itself. If “first” or “second” is involved, it should be understood as being used to distinguish technical features, and should not be understood as indicating or implying relative importance or implicitly indicating the number of the indicated technical features or implicitly indicating the order of the indicated technical features.
[0043] The battery cover usually adopts a single-layer explosion-proof valve, and the explosion-proof valve will have a reduction in pressure relief capacity due to various factors. For example, during long-term use, the explosion-proof valve may be impacted and corroded by the gas inside the battery, or impacted or rubbed due to vibration, resulting in reduced sealing performance, material fatigue and wear, etc., thereby reducing the pressure relief capacity of the explosion-proof valve and even causing failure. Alternatively, factors such as ambient temperature and humidity may also affect the pressure relief capacity of the explosion-proof valve. For example, a high temperature environment may cause the performance of the explosion-proof valve material to decline, thereby reducing its pressure relief capacity. The attenuation of the pressure relief capacity of the explosion-proof valve will lead to a decrease in the opening pressure, resulting in the premature opening of the explosion-proof valve. The decline in the sealing performance of the explosion-proof valve will cause gas leakage without the need for pressure relief. The long-term decline in sealing performance may also cause fatigue or damage to the material of the explosion-proof valve, causing it to open prematurely before the predetermined pressure is reached, thereby failing to meet the explosion-proof valve opening EOL (End of Line) node designed for the battery. The EOL (End of Line) node is the termination node in the life cycle of a device or component, indicating that its performance may begin to decline and need to be replaced or repaired. For example, the EOL node of an explosion-proof valve refers to the point in time when the valve opening function of the explosion-proof valve is no longer reliable or no longer meets the design requirements at the end of its service life. Once the explosion-proof valve reaches the EOL node, its valve opening function may not meet safety requirements. The EOL node of the explosion-proof valve is generally designed through a series of tests and life expectancy assessments. The above problems cause the explosion-proof valve to fail prematurely, and therefore cannot meet the designed valve opening EOL node, and thus cannot meet the designed EOL node of the battery. The explosion-proof valve cannot cope with the entire life cycle of the battery, resulting in the battery failing to reach its designed life.
[0044] In the related art, the attenuation of pressure relief capacity is reduced by improving the structure and materials of the explosion-proof valve. However, in conventional usage scenarios, factors affecting the explosion-proof valve still exist. As the use time of the explosion-proof valve increases, once the explosion-proof valve fails prematurely, it will still cause sealing and leakage problems. Therefore, the effect of using this method to reduce the probability of premature failure of the explosion-proof valve is not ideal.
[0045] The embodiment of the present application provides a battery cover, including a first explosion-proof valve and a second explosion-proof valve arranged in sequence from the inside to the outside. In the event of failure of the first explosion-proof valve, the second explosion-proof valve can work normally, thereby avoiding gas leakage and liquid leakage, and effectively ensuring sealing performance and pressure relief capacity. The following is an introduction to the embodiment of the present application in conjunction with the drawings of the specification:
[0046] refer to Figures 1 to 4The battery cover 10 of the first embodiment of the present application includes a cover body 100, a first explosion-proof valve 200 and a second explosion-proof valve 300. The cover body 100 has an inner wall 101 and an outer wall 102 relative to each other. The cover body 100 is provided with an explosion-proof hole 110 that penetrates the inner wall 101 and the outer wall 102 of the cover body 100. The explosion-proof hole 110 is used to set the explosion-proof valve. The first explosion-proof valve 200 covers the explosion-proof hole 110 and is connected to the cover body 100. The second explosion-proof valve 300 is arranged on the outer side of the first explosion-proof valve 200. The inside and the outside are relative. With reference to the orientation of the battery cover 10 when applied to the battery, after assembly, the inner wall 101 of the cover body 100 faces the inside of the battery, and the outer wall 102 faces the outside of the battery. Therefore, the side of the battery cover 10 and its components facing the inside of the battery can be recorded as the inside, and the side away from the inside of the battery can be recorded as the outside.
[0047] Among them, reference Figures 2 to 4 The first explosion-proof valve 200 includes a first explosion-proof portion 210 corresponding to the explosion-proof hole 110, and a first connecting portion 220 arranged around the first explosion-proof portion 210. The first explosion-proof valve 200 is configured such that when the pressure is released, the first explosion-proof portion 210 opens, and the gas inside the battery can be released to the outside to achieve pressure release. The first connecting portion 220 is sealed and connected to the cover body 100, so that when the first explosion-proof valve 200 is not opened, the explosion-proof hole 110 can be sealed on the inner side of the second explosion-proof valve 300 to prevent the gas pressure inside the cover body 100 from affecting the pressure relief capacity of the second explosion-proof valve 300.
[0048] refer to Figures 4 to 6 The second explosion-proof valve 300 includes a second explosion-proof portion 310 corresponding to the explosion-proof hole 110, and a second connecting portion 320 arranged around the second explosion-proof portion 310. There is a gap 330 between the second explosion-proof portion 310 and the first explosion-proof portion 210, which can provide a deformation space for the opening of the first explosion-proof portion 210, so that the first explosion-proof valve 200 can be opened smoothly. The second connecting portion 320 is sealed and connected to the first connecting portion 220 or the cover body 100, and the second explosion-proof valve 300 at least covers the first explosion-proof portion 210, thereby sealing the first explosion-proof portion 210 on the outside. After the first explosion-proof valve 200 fails prematurely, the second explosion-proof valve 300 works normally and can ensure a certain valve opening pressure to ensure that it can be effectively opened to release the pressure inside the battery when needed (for example, when the preset pressure is reached), which is conducive to meeting the explosion-proof valve opening EOL node. From the perspective of the battery cover 10 as a whole, the risk of gas leakage and liquid leakage at the explosion-proof hole 110 is reduced.
[0049] Moreover, as can be seen from the foregoing, an important reason for the attenuation of the pressure relief capacity of the explosion-proof valve is the impact and corrosion of the gas inside the battery. The cover plate body 100, the first explosion-proof valve 200 and the second explosion-proof valve 300 of the embodiment of the present application adopt the above-mentioned structural arrangement, so that the gas inside the battery mainly acts on the first explosion-proof valve 200, and the second explosion-proof valve 300 is protected from the influence of the gas inside the battery because it is blocked by the first explosion-proof valve 200 on the inside, thereby effectively ensuring the pressure relief capacity to ensure that the pressure inside the battery can be effectively discharged when needed.
[0050] refer to Figures 4 to 6 In some embodiments, the second connection part 320 is sealedly connected to the first connection part 220, so that the first explosion-proof valve 200 and the second explosion-proof valve 300 can be assembled and connected as a component, and then the first connection part 220 is assembled and connected to the cover body 100, or the second connection part 320 is sealedly connected to the cover body 100.
[0051] The second explosion-proof valve 300 at least covers the first explosion-proof part 210, thereby sealing the first explosion-proof part 210 from the outside. The second explosion-proof valve 300 can only cover the first explosion-proof part 210, for example, by sealingly connecting to the first connection part 220 through the second connection part 320, so that the second connection part 320 surrounds the first explosion-proof part 210, thereby covering the first explosion-proof part 210 from the outside, or, it can also be sealed to the cover plate body 100 through the second connection part 320, so that the second explosion-proof valve 300 covers the explosion-proof hole 110, thereby ensuring that the first explosion-proof part 210 is covered from the outside. Therefore, when the first explosion-proof valve 200 fails in advance and is opened, the second explosion-proof valve 300 can work normally, and the first explosion-proof part 210 opened in advance is covered from the outside by the second explosion-proof valve 300, avoiding gas leakage and liquid leakage, playing a sealing and explosion-proof role, and will not cause the overall failure of the explosion-proof valve at the explosion-proof hole 110.
[0052] The first connection part 220 and the cover plate body 100 may be sealed and connected by laser welding, and the second connection part 320 and the first connection part 220 may be sealed and connected by laser welding.
[0053] refer to Figures 4 to 6In some embodiments of the battery cover 10, a groove 221 is provided on the outer side of the first connection portion 220 of the first explosion-proof valve 200, and the groove 221 is recessed inwardly. The second connection portion 320 is located in the groove 221 and is sealed and connected to the first connection portion 220. The provision of the groove 221 can facilitate the positioning of the second explosion-proof valve 300, thereby facilitating the assembly and connection of the second explosion-proof valve 300 with the first explosion-proof valve 200. Specifically, the groove 221 may include a bottom wall 222 and a side wall 223. The bottom wall 222 faces outward and can be used to support the second connection part 320 of the second explosion-proof valve 300. The side wall 223 of the groove 221 is arranged on the outer edge of the bottom wall 222 and extends outward from the bottom wall 222. When the second connection part 320 is placed in the groove 221, the side wall 223 can surround the outer periphery of the second connection part 320. The side wall 223 can circumferentially limit the second connection part 320 to facilitate the positioning connection of the second connection part 320 and the first connection part 220.
[0054] refer to Figures 4 to 6 In some embodiments, the second connection part 320 includes a connection section 321 and an extension section 322. The connection section 321 is located on the inner side of the second explosion-proof part 310 and is connected to the first connection part 220. The extension section 322 is connected between the second explosion-proof part 310 and the connection section 321. Thus, the second explosion-proof valve 300 forms a convex structure protruding outward relative to the first explosion-proof part 210. When the connection section 321 is connected to the first connection part 220, the extension section 322 can be supported between the connection section 321 and the second explosion-proof part 310, so that a gap 330 is left between the second explosion-proof part 310 and the first explosion-proof part 210 to provide the space required for the first explosion-proof part 210 to open outward, thereby ensuring the smooth opening of the first explosion-proof part 210.
[0055] refer to Figures 4 to 6 In some embodiments, the thickness of at least a portion of the extension section 322 is greater than the thickness of the second explosion-proof part 310, so that the strength of the extension section 322 is greater than the second explosion-proof part 310, which can ensure that the extension section 322 stably supports the second explosion-proof part 310, wherein the thickness of the extension section 322 can gradually increase from one end connected to the second explosion-proof part 310 to the other end connected to the connecting section 321, thereby playing the role of a reinforcing rib, and the thickness of the connecting section 321 can be greater than the second explosion-proof part 310, so that the end of the extension section 322 with a larger thickness can be conveniently connected to the connecting section 321.
[0056] The gap 330 can also be formed between the first explosion-proof part 210 and the second explosion-proof part 310 in other ways. For example, in some embodiments, the second connection part 320 of the second explosion-proof valve 300 can also be connected to a position on the cover body 100 that is a certain distance away from the first connection part 220, so that a gap 330 is left between the first explosion-proof part 210 and the second explosion-proof part 310. For example, the second connection part 320 is connected to the outer wall 102 of the cover body 100, or an inwardly recessed groove is provided on the outer wall 102 of the cover body 100, and the second connection part 320 can be provided in the groove and sealedly connected to the cover body 100, wherein the first explosion-proof valve 200 and the second explosion-proof valve 300 can both adopt a sheet structure, and can achieve sealing and explosion-proof functions after being fixedly connected.
[0057] Specifically, the second explosion-proof valve 300 can be formed into an integrated structure by an integrated molding process. Similarly, the first explosion-proof valve 200 can also be formed into an integrated structure by an integrated molding process.
[0058] In the embodiment of the present application, the valve opening pressures of the first explosion-proof valve 200 and the second explosion-proof valve 300 may be the same or different. For example:
[0059] In some embodiments, the valve opening pressure of the second explosion-proof valve 300 can be greater than the valve opening pressure of the first explosion-proof valve 200. Since the first explosion-proof valve 200 blocks the inner side of the second explosion-proof valve 300, the gas inside the battery acts on the first explosion-proof valve 200 to attenuate its pressure relief capacity. When used, the first explosion-proof valve 200 will open before the second explosion-proof valve 300. At this time, the internal pressure of the battery has not yet reached the valve opening pressure of the second explosion-proof valve 300, and the second explosion-proof valve 300 can be used normally to achieve effective sealing and explosion-proof. Therefore, when used, the valve opening pressure of the second explosion-proof valve 300 can be configured according to the preset internal pressure of the battery. As the internal gas pressure of the battery increases, the first explosion-proof part 210 of the first explosion-proof valve 200 will open before the second explosion-proof part 310 of the second explosion-proof valve 300. At this time, the internal pressure of the battery has not yet reached the preset pressure, and the second explosion-proof valve 300 will not be opened, thereby ensuring the service life of the battery. As the gas pressure inside the battery further increases, when the preset pressure is reached, the second explosion-proof valve 300 can be effectively opened to release the pressure inside the battery and ensure the safety performance of the battery.
[0060] Alternatively, in some embodiments, the valve opening pressures of the second explosion-proof valve 300 and the second explosion-proof valve 300 may be equal, and therefore, the valve opening pressures of the first explosion-proof valve 200 and the second explosion-proof valve 300 may be configured according to the preset internal pressure of the battery. In the case where the pressure relief capacity of the first explosion-proof valve 200 is attenuated, as the internal gas pressure of the battery increases, the first explosion-proof valve 200 will open before reaching the designed valve opening pressure. At this time, the internal pressure of the battery has not yet reached the valve opening pressure of the second explosion-proof valve 300, and the second explosion-proof valve 300 can be used normally, achieving effective sealing and explosion-proof, and ensuring the service life of the battery. In the case where the pressure relief capacity of the first explosion-proof valve 200 is not attenuated, the first explosion-proof valve 200 and the second explosion-proof valve 300 can be opened synchronously as the internal pressure of the battery reaches the preset pressure, thereby ensuring the safety performance of the battery.
[0061] As an example, the valve opening pressure of the first explosion-proof valve 200 is configured in the range of 0.4Mpa to 0.7MPa, for example, it can be 0.4Mpa, 0.5Mpa, 0.6Mpa, 0.7Mpa or any other value in the range of 0.4Mpa to 0.7MPa. The valve opening pressure in this range is suitable for common batteries, which can effectively prevent the risk of explosion caused by excessive pressure inside the battery cell, and prevent the first explosion-proof valve 200 from opening prematurely and failing due to too small pressure. The premature opening of the first explosion-proof valve 200 will cause the gas inside the battery to directly affect the pressure relief capacity of the second explosion-proof valve 300 in the subsequent cycle after the first explosion-proof valve 200 is opened, resulting in the battery possibly failing to meet the explosion-proof valve opening EOL node.
[0062] As an example, the valve opening pressure of the second explosion-proof valve 300 is configured in the range of 0.6MPa to 1.0MPa, for example, it can be 0.6Mpa, 0.7Mpa, 0.8Mpa, 0.9Mpa, 1.0Mpa or any other value in the range of 0.6MPa to 1.0MPa. The valve opening pressure in this range is suitable for common batteries, which can effectively prevent the risk of explosion caused by excessive internal pressure of the battery, and prevent the second explosion-proof valve 300 from opening in advance when the first explosion-proof valve 200 is opened in advance due to too low pressure, resulting in the battery possibly failing to meet the explosion-proof valve opening EOL node.
[0063] The opening pressure of the explosion-proof valve can be determined based on the thickness of the thinnest part of the explosion-proof part. The thinnest part of the explosion-proof part will break under a certain pressure to release pressure. The pressure at this time can be considered as the opening pressure. The method of forming the thinnest part on the explosion-proof part is usually to set a notch on the explosion-proof part. The notch does not penetrate the explosion-proof part. The depth of the notch is less than the thickness of the explosion-proof part, so that there is a certain residual thickness. The remaining residual thickness forms the thinnest part of the explosion-proof part. Reference Figure 4 , Figures 8 to 11In some embodiments of the present application, a first notch 230 (such as Figure 4 , Fig. 9 and Fig.11 ), the first notch 230 is recessed toward the inside; or, the first explosion-proof part 210 is provided with a first notch 230 on the inside, and the first notch 230 is recessed toward the outside. The first notch 230 can be made into a closed ring (such as Fig. 9 ) or an open ring, or can also be made into a long strip shape or other regular or irregular shapes. The cross section of the first notch 230 can be a rectangular structure (such as Fig.11 ), arc, V-shape or trapezoid, etc.
[0064] refer to Figures 4 to 7 The second explosion-proof portion 310 is provided with a second notch 340 on the outside, and the second notch 340 is recessed toward the inside; or the second explosion-proof portion 310 is provided with a second notch 340 (such as Figure 4 , Figure 7 and Figure 8 ), the second notch 340 is recessed toward the outside. The second notch 340 can be made into a closed ring (such as Figure 8 ) or an open ring, or can also be made into a long strip shape or other regular or irregular shapes. The cross section of the second notch 340 can be a rectangular structure (such as Figure 7 ), arc, V-shape or trapezoidal, etc.
[0065] In the above embodiment, the depth of the first notch 230 is less than the thickness of the first explosion-proof part 210, and the depth of the second notch 340 is less than the thickness of the second explosion-proof part 310, so that the residual thickness of the first explosion-proof part 210 at the first notch 230 forms the thinnest position on the first explosion-proof part 210, and the residual thickness of the second explosion-proof part 310 at the second notch 340 forms the thinnest position on the second explosion-proof part 310. Therefore, no matter whether the first notch 230 is arranged on the inside or outside, made into any of the above shapes, and adopts any of the above cross-sectional structures, the thinnest position can be formed on the first explosion-proof part 210. Similarly, no matter whether the second notch 340 is arranged on the inside or outside, made into any of the above shapes, and adopts any of the above cross-sectional structures, the thinnest position can be formed on the second explosion-proof part 310. These thinnest positions are also the concentration points of force, which can ensure tearing from the position under the corresponding pressure, realize the management of the bursting position, and avoid affecting the structural stability of other positions of the explosion-proof valve.
[0066] In the above embodiment, compared with the solution of setting the first notch 230 on the inside of the first explosion-proof part 210, it can effectively prevent the electrolyte from accumulating or forming crystals at the notch, reduce the corrosion of the electrolyte to the first explosion-proof part 210, and thus reduce the impact on the pressure relief capacity of the first explosion-proof valve 200.
[0067] In the above embodiment, the second notch 340 is arranged on the inner side of the second explosion-proof part 310, which can facilitate the processing and manufacturing of the second notch 340. For example, in the solution where the second explosion-proof valve 300 adopts the above-mentioned convex hull structure, when processing and forming the second notch 340, the inner space of the convex hull structure is limited, and it is not convenient to set an abutment tooling. If the second notch 340 is arranged on the outside, the second explosion-proof part 310 is supported by the second connecting part 320 during processing, which may cause the second connecting part 320 to deform. However, if the second notch 340 is arranged on the inner side of the second explosion-proof part 310, an abutment tooling can be set on the outer side of the second explosion-proof part 310 during processing to achieve support, thereby reducing the extrusion of other parts of the second explosion-proof valve 300, facilitating manufacturing and ensuring quality.
[0068] The notch design can also adjust the valve opening pressure. For example, the residual thickness can be calculated according to the bursting pressure required by the battery system, so that the valve opening pressure can be adjusted by setting the residual thickness of the notch. Fig.11 , the thickness of the first explosion-proof part 210 is D1, the depth of the first notch 230 is H1, D1>H1, so the residual thickness of the first notch 230 is D1-H1. Without considering the influence of other factors (such as notch area, shape, position, etc.), generally, the greater the residual thickness of the first notch 230, the greater the valve opening pressure of the first explosion-proof part 210. Figure 7 , the thickness of the second explosion-proof part 310 is D2, the depth of the second notch 340 is H2, D2>H2, so the residual thickness of the second notch 340 is D2-H2. Without considering the influence of other factors (such as cross-section, shape, position, etc.), the greater the residual thickness of the second notch 340, the greater the valve opening pressure of the second explosion-proof part 310.
[0069] refer to Figure 7 and Fig.11 In some embodiments, the residual thickness of the first notch 230 and the second notch 340 satisfies: D2-H2≥D1-H1, that is, the residual thickness D1-H1 of the first explosion-proof valve 200 is less than or equal to the residual thickness D2-H2 of the second explosion-proof valve 300, thereby making the valve opening pressure of the first explosion-proof valve 200 lower than the valve opening pressure of the second explosion-proof valve 300. Specifically, the residual thickness of the notch located at the first explosion-proof valve 200 satisfies: D1-H1≥45μm.
[0070] refer to Figure 4 , Fig.12 and Fig.13In some embodiments, the explosion-proof hole 110 on the cover body 100 includes a through hole 111 and a step hole 112 that are connected to each other. The step hole 112 is located on the inner side of the through hole 111. The through hole 111 passes through the outer surface of the cover body 100. The step hole 112 passes through the inner wall 101 of the cover body 100. The first explosion-proof valve 200 is connected to the step hole 112 and covers the through hole 111, which can be conveniently connected to the cover body 100 and save space along the inner and outer directions. Among them, a step portion 113 surrounding the through hole 111 is formed between the hole wall of the step hole 112 and the hole wall of the through hole 111. The first explosion-proof valve 200 is connected to the step portion 113 and covers the through hole 111. The step portion 113 provides a connection area for the connection between the first explosion-proof valve 200 and the cover body 100, which can be conveniently achieved by laser welding at the step portion 113 to achieve a sealed connection between the two.
[0071] refer to Figure 2 and Figure 4 In some embodiments, the battery cover 10 further includes a protective member 400, which is disposed on the outside of the second explosion-proof valve 300 and at least covers the second explosion-proof portion 310, and is used to protect the second explosion-proof valve 300 and prevent external damage from affecting the pressure relief capacity of the second explosion-proof valve 300. The protective member 400 may be connected to the cover body 100. In some embodiments, the edge of the protective member 400 may be provided with an adhesive portion for bonding with the outer surface of the cover body 100. Among them, the second explosion-proof valve 300 is located in the explosion-proof hole 110, and the protective member 400 is attached to the outer surface of the cover body 100 at the explosion-proof hole 110, and covers the explosion-proof hole 110, thereby protecting the second explosion-proof valve 300.
[0072] refer to Figures 1 to 3 and Fig.12 The battery cover 10 of the embodiment of the present application also includes common components such as a pole 500, a riveting block 600, a sealing ring 700, a lower plastic 800, and an upper plastic 900, which can be reasonably adapted according to specific production requirements. As an example:
[0073] The cover body 100 is also provided with two pole holes 120 for riveting the poles 500 . The inner wall 101 and the outer wall 102 of the cover body 100 are both designed with two countersunk holes for positioning and stopping the lower plastic 800 and the upper plastic 900 .
[0074] The pole 500 passes through the pole hole 120 , and the end of the pole 500 located outside the cover body 100 is riveted and fixed to the rivet block 600 . The pole 500 is used for current transmission for the electrode terminal and can be formed by pressing and lathe turning.
[0075] The sealing ring 700 is pressed between the pole 500 and the cover body 100 to achieve sealing and insulation at the pole hole 120. The material may be fluororubber, and the sealing ring 700 may be designed as a step shape or a circular ring.
[0076] The lower plastic 800 is provided with a through hole 810 for the pole 500 to pass through and an exhaust hole 820 for the explosion-proof hole 110 to exhaust air. The lower plastic 800 can support one end of the pole 500 located on the inner side of the cover body 100, and play a role in supporting riveting and insulation. The lower plastic 800 is provided with two positioning bosses for positioning and assembling with the cover body 100, and also has a rotation-stopping function.
[0077] The upper plastic 900 can support the riveting and insulation of the riveting block 600 .
[0078] After the riveting block 600 is fixed by riveting, it can be laser welded with the pole 500 to reduce the contact resistance.
[0079] The second aspect of the present application provides a battery, including a battery cover according to any one of the first aspects. When the first explosion-proof valve 200 fails prematurely, the second explosion-proof valve 300 can play an explosion-proof and sealing role, thereby reducing the risk of leakage and ensuring a certain valve opening pressure to ensure that the pressure inside the battery can be effectively discharged when needed to prevent safety accidents such as battery explosion, thereby effectively improving the sealing and safety of the battery.
[0080] The battery pack of the third aspect embodiment of the present application includes multiple batteries of any one of the second aspect embodiments described above. Each battery is provided with the above-mentioned battery cover to effectively improve the sealing and safety of the battery, thereby effectively avoiding leakage contamination between the batteries inside the battery pack, thereby improving the safety of the battery pack.
[0081] The vehicle of the fourth embodiment of the present application comprises a plurality of batteries of any one of the second embodiments, or comprises a battery pack of any one of the third embodiments.
[0082] The vehicle involved in this application may be a private car, such as a sedan, SUV, MPV or pickup truck. The vehicle may also be an operating vehicle, such as a van, a bus, a small truck or a large trailer. The vehicle may be a new energy vehicle, such as a hybrid vehicle or a pure electric vehicle. The battery and / or battery pack including the above-mentioned battery cover 10 may be applied to the power system of the vehicle. By providing the above-mentioned battery cover, each battery can effectively improve the sealing and safety, thereby improving the safety of the vehicle.
[0083] The embodiments of the present application are described in detail above in conjunction with the accompanying drawings, but the present application is not limited to the above embodiments. Various changes can be made within the knowledge of ordinary technicians in the relevant technical field without departing from the purpose of the present application. In addition, the embodiments of the present application and the features in the embodiments can be combined with each other without conflict.
Claims
1. A battery cover, characterized in that: include: The cover plate body has an inner wall and an outer wall opposite to each other, and the cover plate body is provided with an explosion-proof hole penetrating the inner wall and the outer wall; a first explosion-proof valve, the first explosion-proof valve covers the explosion-proof hole, the first explosion-proof valve comprises a first explosion-proof portion corresponding to the explosion-proof hole, and a first connecting portion arranged around the first explosion-proof portion, the first connecting portion is sealed and connected to the cover plate body, and the first explosion-proof valve is configured such that the first explosion-proof portion opens when pressure is released; The second explosion-proof valve is arranged on the outer side of the first explosion-proof valve, and includes a second explosion-proof part corresponding to the explosion-proof hole, and a second connecting part arranged around the second explosion-proof part, there is a gap between the second explosion-proof part and the first explosion-proof part, the second connecting part is sealed and connected to the first connecting part or the cover plate body, and the second explosion-proof valve at least covers the first explosion-proof part.
2. The battery cover according to claim 1, characterized in that: A groove is provided on the outer side of the first connection part, and the groove is recessed inwardly. The second connection part is located in the groove and is sealed and connected to the first connection part.
3. The battery cover according to claim 2, characterized in that: The groove includes a bottom wall and a side wall, wherein the bottom wall faces outward, the side wall is arranged around the outer edge of the bottom wall and extends outward from the bottom wall, and the side wall surrounds the outer periphery of the second connecting portion.
4. The battery cover according to claim 1, characterized in that: The second connecting portion includes a connecting section and an extending section. The connecting section is located inside the second explosion-proof portion and connected to the first connecting portion. The extending section is connected between the second explosion-proof portion and the connecting section.
5. The battery cover according to claim 4, characterized in that: The thickness of the extension section gradually increases from an end connected to the second explosion-proof portion to an end connected to the connection section.
6. The battery cover according to claim 1, characterized in that: The valve opening pressure of the second explosion-proof valve is greater than or equal to the valve opening pressure of the first explosion-proof valve.
7. The battery cover according to claim 6, characterized in that: The valve opening pressure of the first explosion-proof valve is configured within a range of 0.4 MPa to 0.7 MPa, and / or the valve opening pressure of the second explosion-proof valve is configured within a range of 0.6 MPa to 1.0 MPa.
8. The battery cover according to claim 1, characterized in that: A first notch is provided on the outer side of the first explosion-proof portion, and the first notch is recessed toward the inner side, or a first notch is provided on the inner side of the first explosion-proof portion, and the first notch is recessed toward the outer side; A second notch is provided on the outer side of the second explosion-proof portion, and the second notch is recessed toward the inner side, or a second notch is provided on the inner side of the second explosion-proof portion, and the second notch is recessed toward the outer side.
9. The battery cover according to claim 8, characterized in that: The thickness of the first explosion-proof portion is D1, and the depth of the first notch is H1, wherein D1>H1; The thickness of the second explosion-proof portion is D2, and the depth of the second notch is H2, wherein D2>H2, and D2-H2≥D1-H1.
10. The battery cover according to claim 9, characterized in that: In the first explosion-proof valve: D1-H1≥45μm.
11. The battery cover according to claim 1, characterized in that: The explosion-proof hole includes a connected through hole and a step hole, the step hole is located on the inner side of the through hole, the through hole penetrates to the outer wall of the cover body, the step hole penetrates to the inner wall of the cover body, and the first explosion-proof valve is arranged in the step hole and covers the through hole.
12. The battery cover according to claim 1, characterized in that: The battery cover plate further comprises a protective member, which is arranged on the outer side of the second explosion-proof valve and at least covers the second explosion-proof portion, and is connected to the cover plate body.
13. A battery, characterized in that The invention comprises a battery cover as claimed in any one of claims 1 to 12.
14. A battery pack, characterized in that: Comprising a plurality of batteries as claimed in claim 13.
15. A vehicle, characterized in that Comprising a plurality of batteries as claimed in claim 13.