Battery cover plate, battery, battery pack and vehicle

Abstract

The present application relates to the technical field of batteries, and discloses a battery cover plate (10), a battery, a battery pack and a vehicle. The battery cover plate (10) comprises a cover plate body (100), a first explosion-proof valve (200) and a second explosion-proof valve (300), the first explosion-proof valve (200) covering an explosion-proof hole (110), and the second explosion-proof valve (300) being located on the outer side of the first explosion-proof valve (200) and at least covering an explosion-proof part of the first explosion-proof valve (200).

Description

Battery cover, battery, battery pack and vehicle

[0001] CROSS-REFERENCE TO RELATED APPLICATIONS

[0002] This application claims priority to Chinese patent application number 202420488072.4 filed on March 12, 2024, entitled “Battery Cover, Battery, Battery Pack and Vehicle,” the entire contents of which are incorporated herein by reference. Technical Field

[0003] The present application relates to, but is not limited to, the field of battery technology, and in particular to a battery cover, a battery, a battery pack, and a vehicle. Background Art

[0004] Battery covers are typically equipped with explosion-proof valves that open under a certain level of air pressure, releasing gas from the battery. This ensures that internal pressure is released quickly in the event of thermal runaway, preventing a violent explosion. However, in practice, the valve's pressure-relieving capacity degrades as the battery undergoes charging, discharging, and other use scenarios, leading to premature failure and the risk of leakage. Summary of the Invention

[0005] The following is a summary of the subject matter described in detail herein. This summary is not intended to limit the scope of the claims.

[0006] This application proposes a battery cover to address the risk of battery leakage caused by premature failure of an explosion-proof valve. This application also proposes a battery having the battery cover, as well as a battery pack and a vehicle having the battery.

[0007] 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 passes through the inner wall and the outer wall; the first explosion-proof valve covers the explosion-proof hole, and 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 with the cover body, and the first explosion-proof valve is configured to open when the pressure is released; the second explosion-proof valve is arranged on the outside of the first explosion-proof valve, and includes a second explosion-proof portion corresponding to the explosion-proof hole, and a second connecting portion arranged around the second explosion-proof portion, a gap is formed between the second explosion-proof portion and the first explosion-proof portion, the second connecting portion is sealed with the first connecting portion or the cover body, and the second explosion-proof valve at least covers the first explosion-proof portion.

[0008] The battery cover according to the embodiment of the first aspect of the present application has at least the following beneficial effects: when applied to a battery, the gap between the first explosion-proof portion and the second explosion-proof portion provides deformation space for the opening of the first explosion-proof portion, 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 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.

[0009] 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 with the first connecting portion.

[0010] 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.

[0011] 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.

[0012] In the battery cover of some embodiments of the present application, the thickness of the extension section gradually increases from the end connected to the second explosion-proof portion to the end connected to the connecting section.

[0013] In some embodiments of the battery cover 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.

[0014] In the battery cover of some embodiments of the present application, the valve opening pressure of the first explosion-proof valve is configured to be within the range of 0.4 MPa to 0.7 MPa, and / or the valve opening pressure of the second explosion-proof valve is configured to be within the range of 0.6 MPa to 1.0 MPa.

[0015] In some embodiments of the battery cover 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.

[0016] In some embodiments of the battery cover of the present application, 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.

[0017] In the battery cover of some embodiments of the present application, in the first explosion-proof valve: D1-H1≥45μm.

[0018] 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 to the outer wall of the cover body, the step hole passes through to the inner wall of the cover body, and the first explosion-proof valve is arranged in the step hole and seals the through hole.

[0019] In some embodiments of the battery cover of the present application, the battery cover further 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.

[0020] The battery of the second 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, preventing safety accidents such as battery explosion, thereby effectively improving the sealing and safety of the battery.

[0021] The battery pack of the third embodiment of the present application includes multiple batteries of any one of the above-mentioned second embodiments. By providing the above-mentioned battery cover, each battery can 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.

[0022] The vehicle of the fourth embodiment of the present application includes a plurality of batteries as described in any one of the embodiments of the second aspect. The battery cover provided on each battery can effectively improve the sealing and safety, thereby improving the safety of the vehicle.

[0023] Additional aspects and advantages of the present application will be given in part in the description below, and in part will become obvious from the description below, or will be learned through practice of the present application. BRIEF DESCRIPTION OF THE DRAWINGS

[0024] FIG1 is a schematic structural diagram of a battery cover according to an embodiment of the present application;

[0025] FIG2 is an exploded view of the battery cover shown in FIG1 ;

[0026] FIG3 is a schematic cross-sectional view of a battery cover along the axial direction of an explosion-proof hole according to an embodiment;

[0027] FIG4 is a partial enlarged schematic diagram of point A in FIG3 ;

[0028] FIG5 is a schematic structural diagram of a second explosion-proof valve in one embodiment;

[0029] FIG6 is a schematic cross-sectional view of the second explosion-proof valve shown in FIG5 along the axial direction of the explosion-proof hole;

[0030] FIG7 is a partial enlarged schematic diagram of point B in FIG6;

[0031] FIG8 is a schematic structural diagram of the second explosion-proof valve shown in FIG5 from another perspective;

[0032] FIG9 is a schematic structural diagram of a first explosion-proof valve in one embodiment;

[0033] FIG10 is a schematic cross-sectional view of the first explosion-proof valve shown in FIG9 along the axial direction of the explosion-proof hole;

[0034] Figure 11 is a partial enlarged schematic diagram of point C in Figure 9;

[0035] FIG12 is a schematic cross-sectional view of the cover plate body along the axial direction of the explosion-proof hole in one embodiment; and

[0036] FIG13 is a partial enlarged schematic diagram of point D in FIG12 .

[0037] Reference numerals:

[0038] Battery cover 10;

[0039] Cover plate body 100; inner wall 101; outer wall 102; explosion-proof hole 110; through hole 111; stepped hole 112; stepped portion 113; pole hole 120;

[0040] 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;

[0041] 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;

[0042] Protective component 400; terminal 500; rivet block 600; sealing ring 700; lower plastic 800; via 810; vent hole 820; upper plastic 900. DETAILED DESCRIPTION

[0043] The following will clearly and completely describe the concept and technical effects of this application in conjunction with the embodiments to fully understand the purpose, features and effects of this application. Obviously, the embodiments described are only part of the embodiments of this application, not all of them. Based on the embodiments of this application, other embodiments obtained by those skilled in the art without creative work are all within the scope of protection of this application.

[0044] 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 component 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.

[0045] In the description of the embodiments of the present application, if a certain feature is referred to as being “set,” “fixed,” “connected,” or “installed” on another feature, it may be directly set, fixed, or connected on the other feature, or it may be indirectly set, fixed, connected, or installed on the other 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.

[0046] Battery covers typically utilize single-layer explosion-proof valves, whose pressure relief capabilities can degrade due to various factors. For example, over extended use, the valve may be subject to impact and corrosion from internal battery gases, or vibration-induced shock or friction, leading to reduced sealing performance, material fatigue, and wear, reducing the valve's pressure relief capacity or even causing it to fail. Alternatively, factors such as ambient temperature and humidity can affect the valve's pressure relief capability. For example, high temperatures can degrade the valve's material properties, reducing its pressure relief capacity. This reduced pressure relief capability can lead to a decrease in opening pressure, causing the valve to open prematurely. This reduced sealing performance can cause gas leakage when pressure relief is not required. Long-term sealing degradation can also cause material fatigue or damage, causing the valve to open prematurely before the desired pressure is reached, potentially failing to meet the battery's designed valve opening end-of-line (EOL) threshold. The EOL (End of Line) threshold is the end point in the lifecycle of a device or component, marking the beginning of potential performance degradation and the need for replacement or repair. For example, the EOL point of an explosion-proof valve refers to the point at which its opening function is no longer reliable or meets design requirements at the end of its service life. Once the valve reaches its EOL point, its opening function may no longer meet safety requirements. The EOL point of an explosion-proof valve is typically designed through a series of tests and life expectancy assessments. However, the aforementioned issues can cause the valve to fail prematurely, failing to meet the designed EOL point. Consequently, the valve also fails to meet the designed EOL point of the battery. The valve cannot handle the entire battery life cycle, causing the battery to fail to achieve its designed lifespan.

[0047] In related technologies, the attenuation of pressure relief capacity is reduced by improving the structure and materials of explosion-proof valves. However, in conventional usage scenarios, factors affecting explosion-proof valves still exist. As the use time of explosion-proof valves increases, once the explosion-proof valves fail prematurely, it will still cause sealing problems and leakage problems. Therefore, the effect of using this method to reduce the probability of premature failure of explosion-proof valves is not ideal.

[0048] The present invention provides a battery cover, including a first explosion-proof valve and a second explosion-proof valve arranged sequentially from the inside to the outside. If the first explosion-proof valve fails, the second explosion-proof valve can still function normally, thereby preventing gas and liquid leakage and effectively ensuring sealing performance and pressure relief capacity. The following describes the present invention in conjunction with the accompanying drawings:

[0049] Referring to Figures 1 to 4, a battery cover 10 according to a 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 opposing inner and outer walls 101 and 102. The cover body 100 is provided with an explosion-proof hole 110 extending through the inner and outer walls 101, 102 of the cover body 100. The explosion-proof hole 110 is used to accommodate the explosion-proof valve. The first explosion-proof valve 200 seals the explosion-proof hole 110 and is connected to the cover body 100. The second explosion-proof valve 300 is located outside the first explosion-proof valve 200. The terms "inside" and "outside" are relative terms. With reference to the orientation of the battery cover 10 when applied to a battery, after assembly, the inner wall 101 of the cover body 100 faces the interior of the battery, while the outer wall 102 faces the exterior of the battery. Therefore, the side of the battery cover 10 and its components facing the interior of the battery can be referred to as the "inside," and the side facing away from the interior can be referred to as the "outside."

[0050] 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 with the cover plate body 100, so that when the first explosion-proof valve 200 is not opened, the explosion-proof hole 110 can be sealed on the inside of the second explosion-proof valve 300 to prevent the gas pressure inside the cover plate body 100 from affecting the pressure relief capacity of the second explosion-proof valve 300.

[0051] Referring 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. A gap 330 is defined between the second explosion-proof portion 310 and the first explosion-proof portion 210, providing deformation space for the first explosion-proof portion 210 to open, thereby enabling the first explosion-proof valve 200 to open smoothly. The second connecting portion 320 is sealedly connected to the first connecting portion 220 or the cover body 100. The second explosion-proof valve 300 at least covers the first explosion-proof portion 210, thereby sealing the first explosion-proof portion 210 from the outside. If the first explosion-proof valve 200 fails prematurely, the second explosion-proof valve 300 will function normally, maintaining a certain valve opening pressure to ensure that it can effectively open to release internal battery pressure when needed (e.g., when a preset pressure is reached). This helps meet the explosion-proof valve opening end-of-life (EOL) node. Overall, the battery cover 10 reduces the risk of gas and liquid leakage at the explosion-proof hole 110.

[0052] 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.

[0053] 4 to 6 , in some embodiments, the second connection portion 320 is sealedly connected to the first connection portion 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 portion 220 is assembled and connected to the cover plate body 100 , or the second connection portion 320 is sealedly connected to the cover plate body 100 .

[0054] The second explosion-proof valve 300 covers at least the first explosion-proof portion 210, thereby sealing the first explosion-proof portion 210 from the outside. The second explosion-proof valve 300 can only cover the first explosion-proof portion 210, for example, by being sealedly connected to the first connection portion 220 via the second connection portion 320, so that the second connection portion 320 surrounds the first explosion-proof portion 210, thereby sealing the first explosion-proof portion 210 from the outside. Alternatively, the second explosion-proof valve 300 can be sealed to the cover plate body 100 via the second connection portion 320, so that the second explosion-proof valve 300 covers the explosion-proof hole 110, thereby ensuring that the first explosion-proof portion 210 is sealed from the outside. Therefore, in use, if the first explosion-proof valve 200 fails prematurely and is opened, the second explosion-proof valve 300 can still operate normally. The prematurely opened first explosion-proof portion 210 is sealed from the outside by the second explosion-proof valve 300, preventing air and liquid leakage, providing a sealing and explosion-proof function, and preventing the entire explosion-proof valve at the explosion-proof hole 110 from failing.

[0055] The first connection portion 220 and the cover plate body 100 may be sealed and connected by laser welding, and the second connection portion 320 and the first connection portion 220 may be sealed and connected by laser welding.

[0056] 4 to 6 , in some embodiments of the battery cover 10, a groove 221 is provided on the outer side of the first connecting portion 220 of the first explosion-proof valve 200, and the groove 221 is recessed inward. The second connecting portion 320 is located in the groove 221 and is sealed with the first connecting portion 220. The provision of the groove 221 facilitates 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, thereby facilitating the positioning connection of the second connection part 320 with the first connection part 220.

[0057] 4 to 6 , in some embodiments, the second connection portion 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 portion 310 and is connected to the first connection portion 220. The extension section 322 is connected between the second explosion-proof portion 310 and the connection section 321. As a result, the second explosion-proof valve 300 forms a convex structure protruding outward relative to the first explosion-proof portion 210. When the connection section 321 is connected to the first connection portion 220, the extension section 322 can be supported between the connection section 321 and the second explosion-proof portion 310, so that a gap 330 is left between the second explosion-proof portion 310 and the first explosion-proof portion 210 to provide the space required for the first explosion-proof portion 210 to open outward, thereby ensuring the smooth opening of the first explosion-proof portion 210.

[0058] 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 portion 310 , so that the strength of the extension section 322 is greater than that of the second explosion-proof portion 310 , thereby ensuring that the extension section 322 provides stable support for the second explosion-proof portion 310 . The thickness of the extension section 322 may gradually increase from one end connected to the second explosion-proof portion 310 to the end connected to the connecting section 321 , thereby acting as a reinforcing rib. The thickness of the connecting section 321 may be greater than that of the second explosion-proof portion 310 , so that the end of the extension section 322 with a larger thickness may be conveniently connected to the connecting section 321 .

[0059] A 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 sealed with the cover body 100, wherein the first explosion-proof valve 200 and the second explosion-proof valve 300 can both adopt a sheet structure, which can achieve sealing and explosion-proof functions after being fixedly connected.

[0060] Specifically, the second explosion-proof valve 300 can be formed into an integral structure by an integral molding process. Similarly, the first explosion-proof valve 200 can also be formed into an integral structure by an integral molding process.

[0061] 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:

[0062] In some embodiments, the opening pressure of the second explosion-proof valve 300 can be greater than the opening pressure of the first explosion-proof valve 200. Because the first explosion-proof valve 200 blocks the inner side of the second explosion-proof valve 300, the internal gas of the battery acts on the first explosion-proof valve 200, causing its pressure relief capacity to be reduced. During use, 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 opening pressure of the second explosion-proof valve 300, and the second explosion-proof valve 300 can function normally, achieving effective sealing and explosion protection. Therefore, during use, the opening pressure of the second explosion-proof valve 300 can be configured according to the preset internal pressure of the battery. As the internal pressure of the battery increases, the first explosion-proof portion 210 of the first explosion-proof valve 200 will open before the second explosion-proof portion 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 open, thereby ensuring the service life of the battery. As the internal gas pressure of 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.

[0063] Alternatively, in some embodiments, the opening pressures of the second explosion-proof valve 300 and the second explosion-proof valve 300 can be equal. Thus, the opening pressures of the first explosion-proof valve 200 and the second explosion-proof valve 300 can be configured based on a preset internal battery pressure. If the pressure relief capability of the first explosion-proof valve 200 is attenuated, as the internal battery pressure increases, the first explosion-proof valve 200 will open before reaching the designed opening pressure. At this point, the internal battery pressure has not yet reached the opening pressure of the second explosion-proof valve 300, and the second explosion-proof valve 300 can function normally, achieving effective sealing and explosion protection, thereby ensuring the battery's service life. If the pressure relief capability of the first explosion-proof valve 200 is not attenuated, the first explosion-proof valve 200 and the second explosion-proof valve 300 can open simultaneously as the internal battery pressure reaches the preset pressure, thereby ensuring the safety of the battery.

[0064] As an example, the valve opening pressure of the first explosion-proof valve 200 is configured within the range of 0.4 MPa to 0.7 MPa, for example, it can be 0.4 MPa, 0.5 MPa, 0.6 MPa, 0.7 MPa, or any other value within the range of 0.4 MPa to 0.7 MPa. This range of valve opening pressure is suitable for common batteries and can effectively prevent the risk of explosion caused by excessive internal pressure in the battery cell, as well as prevent the first explosion-proof valve 200 from prematurely opening and failing due to insufficient pressure. Premature opening of the first explosion-proof valve 200 can cause the gas inside the battery to directly affect the pressure relief capacity of the second explosion-proof valve 300 in subsequent cycles after the first explosion-proof valve 200 is opened, resulting in the battery possibly failing to meet the explosion-proof valve opening EOL node.

[0065] As an example, the valve opening pressure of the second explosion-proof valve 300 is configured within the range of 0.6 MPa to 1.0 MPa, for example, 0.6 MPa, 0.7 MPa, 0.8 MPa, 0.9 MPa, 1.0 MPa, or any other value within the range of 0.6 MPa to 1.0 MPa. This valve opening pressure range is suitable for common batteries and can effectively prevent the risk of explosion caused by excessive internal pressure in the battery, as well as prevent the premature opening of the second explosion-proof valve 300 due to insufficient pressure when the first explosion-proof valve 200 is prematurely opened, which may cause the battery to fail to meet the explosion-proof valve opening end-of-life (EOL) node.

[0066] The valve 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, thereby releasing pressure. The pressure at this time can be considered as the valve opening pressure. A common method of forming the thinnest part on the explosion-proof part is to provide a notch on the explosion-proof part. The notch does not penetrate the explosion-proof part, and the depth of the notch is less than the thickness of the explosion-proof part, thereby having a certain residual thickness. The remaining residual thickness forms the thinnest part of the explosion-proof part. Referring to Figures 4, 8 to 11, in some embodiments of the present application, a first notch 230 is provided on the outside of the first explosion-proof part 210 (such as Figures 4, 9 and 11), and the first notch 230 is recessed toward the inside; or, a first notch 230 is provided on the inside of the first explosion-proof part 210, and the first notch 230 is recessed toward the outside. The first notch 230 can be made into a closed ring (as shown in FIG9 ) 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 (as shown in FIG11 ), an arc, a V shape or a trapezoid, etc.

[0067] Referring to Figures 4 to 7 , a second notch 340 is provided on the outer side of the second explosion-proof portion 310, and the second notch 340 is recessed inwardly. Alternatively, a second notch 340 is provided on the inner side of the second explosion-proof portion 310 (as shown in Figures 4 , 7 , and 8 ), and the second notch 340 is recessed inwardly. The second notch 340 can be formed into a closed ring (as shown in Figure 8 ) or an open ring, or can be formed into an elongated strip or other regular or irregular shape. The cross-section of the second notch 340 can be rectangular (as shown in Figure 7 ), arc-shaped, V-shaped, trapezoidal, etc.

[0068] In the above embodiment, the depth of the first score 230 is less than the thickness of the first explosion-proof portion 210, and the depth of the second score 340 is less than the thickness of the second explosion-proof portion 310. Consequently, the residual thickness of the first explosion-proof portion 210 at the first score 230 forms the thinnest point on the first explosion-proof portion 210, and the residual thickness of the second explosion-proof portion 310 at the second score 340 forms the thinnest point on the second explosion-proof portion 310. Therefore, regardless of whether the first score 230 is located on the inside or outside, has any of the aforementioned shapes, or adopts any of the aforementioned cross-sectional structures, the thinnest point on the first explosion-proof portion 210 can be formed. Similarly, regardless of whether the second score 340 is located on the inside or outside, has any of the aforementioned shapes, or adopts any of the aforementioned cross-sectional structures, the thinnest point on the second explosion-proof portion 310 can be formed. These thinnest points also serve as points of force concentration, ensuring that tearing occurs at these locations under appropriate pressure, thus managing the bursting point and preventing impact on the structural stability of other locations of the explosion-proof valve.

[0069] In the above embodiment, compared with the solution of arranging the first notch 230 on the outside of the first explosion-proof part 210 on the inside, it can effectively prevent the electrolyte from accumulating or forming crystals at the notch, reduce the corrosion of the electrolyte on the first explosion-proof part 210, and thus reduce the impact on the pressure relief capacity of the first explosion-proof valve 200.

[0070] 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 abutting 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 abutting 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.

[0071] The notch design can also adjust the valve opening pressure. For example, the residual thickness can be calculated based on the burst pressure required by the battery system, thereby adjusting the valve opening pressure by adjusting the residual thickness of the notch. In some embodiments, referring to Figure 11, the thickness of the first explosion-proof portion 210 is D1, and 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 the notch area, shape, and position), the greater the residual thickness of the first notch 230, the greater the valve opening pressure of the first explosion-proof portion 210. Referring to Figure 7, the thickness of the second explosion-proof portion 310 is D2, and 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, and position), the greater the residual thickness of the second notch 340, the greater the valve opening pressure of the second explosion-proof portion 310.

[0072] 7 and 11 , in some embodiments, the residual thickness of the first score 230 and the second score 340 satisfies the following relationship: D2-H2 ≥ D1-H1. In other words, 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. This allows the valve opening pressure of the first explosion-proof valve 200 to be lower than the valve opening pressure of the second explosion-proof valve 300. Specifically, the residual thickness of the score on the first explosion-proof valve 200 satisfies the following relationship: D1-H1 ≥ 45 μm.

[0073] Referring to Figures 4, 12, and 13, in some embodiments, the explosion-proof hole 110 on the cover plate body 100 includes a connected through-hole 111 and a stepped hole 112. The stepped hole 112 is located inside the through-hole 111. The through-hole 111 extends to the outer surface of the cover plate body 100, and the stepped hole 112 extends to the inner wall 101 of the cover plate body 100. The first explosion-proof valve 200 is connected to the stepped hole 112 and covers the through-hole 111, which facilitates connection with the cover plate body 100 and saves space in the inner and outer directions. A stepped portion 113 is formed between the wall of the stepped hole 112 and the wall of the through-hole 111, surrounding the through-hole 111. The first explosion-proof valve 200 is connected to the stepped portion 113 and covers the through-hole 111. The stepped portion 113 provides a connection area for the first explosion-proof valve 200 to connect to the cover plate body 100, facilitating a sealed connection between the two via laser welding at the stepped portion 113.

[0074] 2 and 4 , in some embodiments, the battery cover 10 further includes a protective member 400. The protective member 400 is disposed on the outside of the second explosion-proof valve 300 and covers at least the second explosion-proof portion 310, thereby protecting the second explosion-proof valve 300 from external damage that affects the pressure relief capability of the second explosion-proof valve 300. The protective member 400 can be connected to the cover body 100. In some embodiments, the edge of the protective member 400 can be provided with an adhesive portion for bonding with the outer surface of the cover body 100. The second explosion-proof valve 300 is located within the explosion-proof hole 110. The protective member 400 is adhered 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.

[0075] Referring to Figures 1 to 3 and 12, the battery cover 10 of the embodiment of the present application further includes common components such as a terminal 500, a rivet 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:

[0076] The cover body 100 is further 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 preventing rotation of the lower plastic 800 and the upper plastic 900 .

[0077] 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 to transmit current for the electrode terminal and can be formed by pressing and lathe turning.

[0078] 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 can be fluororubber, and the sealing ring 700 can be designed as a step-shaped or circular ring.

[0079] 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. The lower plastic 800 can support the end of the pole 500 located on the inner side of the cover body 100, and play the role of supporting riveting and insulation. The lower plastic 800 is provided with two positioning bosses for positioning and assembly with the cover body 100, and also has a rotation-stopping function.

[0080] The upper plastic 900 can support the riveting block 600 and provide insulation.

[0081] After the rivet block 600 is fixed by riveting, it can be laser welded with the pole 500 to reduce contact resistance.

[0082] A second aspect embodiment of the present application provides a battery, including a battery cover according to any embodiment of the first aspect above. 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, preventing safety accidents such as battery explosion, thereby effectively improving the sealing and safety of the battery.

[0083] The battery pack of the third embodiment of the present application includes multiple batteries of any one of the above-mentioned second embodiments. By providing the above-mentioned battery cover, each battery can 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.

[0084] The vehicle of the fourth embodiment of the present application includes a plurality of batteries according to any one of the second embodiments, or includes a battery pack according to any one of the third embodiments.

[0085] The vehicle involved in this application can be a private car, such as a sedan, SUV, MPV, or pickup truck. The vehicle can also be an operating vehicle, such as a van, bus, small truck, or large trailer. The vehicle can 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 can be used in 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.

[0086] The embodiments of the present application have been described in detail above with reference to the accompanying drawings. However, the present application is not limited to the above embodiments. Various modifications can be made within the scope of knowledge possessed by 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 of the embodiments can be combined with each other unless there is a conflict.

Claims

1. Battery cover, including: 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 covering the explosion-proof hole, the first explosion-proof valve comprising 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 being sealedly connected to the cover plate body, and the first explosion-proof valve being configured such that the first explosion-proof portion opens when pressure is released; as well as The second explosion-proof valve is arranged on the outside 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 with the first connecting part or the cover plate body. The second explosion-proof valve at least covers the first explosion-proof part.

2. The battery cover according to claim 1, wherein: A groove is provided on the outer side of the first connecting portion, and the groove is recessed inward. The second connecting portion is located in the groove and is sealed with the first connecting portion.

3. The battery cover according to claim 2, wherein: The groove includes a bottom wall and side walls, the bottom wall faces outward, the side walls are arranged around the outer edge of the bottom wall and extend outward from the bottom wall, and the side walls surround the outer periphery of the second connecting portion.

4. The battery cover according to claim 1, wherein: 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, wherein: 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 5, wherein: The thickness of at least a portion of the extending section is greater than the thickness of the second explosion-proof portion, and the thickness of the connecting section is greater than the thickness of the second explosion-proof portion.

7. The battery cover according to claim 1, wherein: 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.

8. The battery cover according to claim 7, wherein: The valve opening pressure of the first explosion-proof valve is configured to be within the range of 0.4 MPa to 0.7 MPa, and / or the valve opening pressure of the second explosion-proof valve is configured to be within the range of 0.6 MPa to 1.0 MPa.

9. The battery cover according to claim 1, wherein: 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.

10. The battery cover according to claim 9, wherein: 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.

11. The battery cover according to claim 10, wherein: In the first explosion-proof valve: D1-H1≥45μm.

12. The battery cover according to claim 1, wherein: 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, and the step hole passes through the inner wall of the cover body. The first explosion-proof valve is arranged in the step hole and covers the through hole.

13. The battery cover according to claim 1, wherein: The battery cover further includes a protective member, which is disposed on the outside of the second explosion-proof valve and at least covers the second explosion-proof portion. The protective member is connected to the cover body.

14. A battery comprising the battery cover according to any one of claims 1 to 13.

15. A battery pack comprising a plurality of batteries according to claim 14.

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