Explosion-proof valve and battery

Abstract

Provided are an explosion-proof valve and a battery. The explosion-proof valve, which is used for being mounted on a battery, comprises a valve body (100) and a burst groove (200). The thickness of the middle part of the valve body (100) is greater than that of the edge of the valve body (100). The burst groove (200) is arranged on the valve body (100) and close to the edge of the valve body (100).

Description

Explosion-proof valves and batteries

[0001] This application claims priority to Chinese Patent Application No. 202421190793.3, filed on May 28, 2024, entitled "Explosion-proof Valve and Battery", the entire contents of which are incorporated herein by reference. Technical Field

[0002] This application relates to, but is not limited to, the technical field of batteries, and particularly to an explosion-proof valve and a battery. Background Technology

[0003] With the continuous development of the battery industry, lithium-ion batteries, with their high energy density, are widely used in the field of power batteries to provide power for vehicle operation.

[0004] The battery includes a battery body, a cover plate, and an explosion-proof valve. The battery body contains battery cells, and the battery body has a receiving cavity for accommodating the cover plate, which is connected to the battery cells. The cover plate is installed in the receiving cavity, and the explosion-proof valve is installed on the cover plate.

[0005] However, under conditions of cell production, battery pack assembly, and vehicle vibration, the stress on the grooves of the explosion-proof valve leads to fatigue cracking and failure, which is quite serious.

[0006] Utility Model Content

[0007] This application provides an explosion-proof valve and a battery that can effectively reduce the stress on the grooves during cell production, battery pack assembly, and vehicle vibration conditions.

[0008] This application provides an explosion-proof valve for installation on a battery, including a valve body and a burst groove, wherein the thickness of the middle part of the valve body is greater than the thickness of the edge of the valve body;

[0009] The bursting groove is located on the valve body and near the edge of the valve body.

[0010] By adopting the above technical solution, and by thickening the middle part of the valve body, compared with an alternative method where the thickness of the middle part of the valve body is the same as that of the edge, this application thickens the middle part of the valve body, which improves the valve body's ability to resist stress. As a result, under the conditions of cell production, pack assembly and vehicle vibration, the stress on the bursting groove is greatly reduced, preventing the bursting groove from being subjected to excessive stress and causing fatigue cracking failure.

[0011] In one possible implementation, the explosion-proof valve provided in this application has a valve body whose thickness gradually decreases from the middle to the edge.

[0012] By adopting the above technical solution, the valve body is set as a gradually decreasing structure from the middle to the edge, which not only improves the valve body's ability to resist stress, but also reduces the production cost of the valve body.

[0013] In one possible implementation, the explosion-proof valve provided in this application has a curved surface on the side of the valve body where the burst groove is located.

[0014] By adopting the above technical solution, the side of the valve body with the burst groove is curved. The curved surface has a higher stress resistance than the flat surface. This not only further improves the stress resistance of the valve body, but also improves the deformation resistance of the middle part of the valve body, avoiding easy damage to the valve body due to external factors.

[0015] In one possible implementation, the explosion-proof valve provided in this application has a valve body with multiple stepped surfaces on one side where the burst groove is provided, and the burst groove is located on the outermost stepped surface of the valve body.

[0016] By adopting the above technical solution, the side of the valve body with the burst groove has multiple stepped surfaces. The burst groove is located on the outermost stepped surface of the valve body, which improves the valve body with stepped layout, thereby making the explosion-proof valve suitable for different batteries.

[0017] In one possible implementation, the explosion-proof valve provided in this application has each step surface as a plane;

[0018] Alternatively, each step surface can be a slope.

[0019] By adopting the above technical solution and defining the shape of the stepped surface, the overall shape of the valve body can be defined, thereby making the valve body suitable for different types of batteries.

[0020] In one possible implementation, the explosion-proof valve provided in this application has the extension direction of the burst groove aligned with the extension direction of a portion of the valve body edge.

[0021] By adopting the above technical solution, when the internal air pressure of the battery reaches the preset pressure, the valve body bursts at the burst groove. The extension direction of the burst groove is consistent with the extension direction of part of the valve body edge, which can increase the size of the opening after the explosion-proof valve bursts, thereby rapidly releasing the internal air pressure of the battery and improving the explosion-proof effect of the explosion-proof valve.

[0022] In one possible implementation, the explosion-proof valve provided in this application has a burst groove whose extension length is at least two-thirds of the circumference of the valve body's edge.

[0023] By adopting the above technical solution and limiting the length of the bursting groove, the length of the bursting groove can be selected according to different types of batteries, so that the explosion-proof valve can be applied to different batteries.

[0024] In one possible implementation, the explosion-proof valve provided in this application has a central thickness that is 2 to 10 times the edge thickness of the valve body.

[0025] By adopting the above technical solution and limiting the thickness of the middle and edge of the valve body, the production and manufacturing cost of the valve body can be reduced while ensuring the valve body's resistance to stress.

[0026] In one possible implementation, the explosion-proof valve provided in this application has a burst groove between the edge of the valve body and a distance between 1 mm and 3 mm, and the residual thickness of the valve body at the burst groove is between 0.03 mm and 0.3 mm.

[0027] By adopting the above technical solution and limiting the length of the burst groove from the edge of the valve body, sufficient space is ensured on the valve body for welding the valve body to the battery, avoiding any impact on the airtightness after welding. By limiting the residual thickness of the valve body at the burst groove, the explosion-proof valve can be applied to different types of batteries.

[0028] This application also provides a battery, including a battery body, a cover plate, and an explosion-proof valve according to any of the above technical solutions, wherein the cover plate has a receiving groove, and the explosion-proof valve is installed in the receiving groove.

[0029] This application provides an explosion-proof valve and a battery. The explosion-proof valve is used to install on the battery and includes a valve body and a burst groove. The thickness of the middle part of the valve body is greater than the thickness of the edge of the valve body. The burst groove is disposed on the valve body and is close to the edge of the valve body. By thickening the middle part of the valve body, this application improves the stress resistance of the valve body, thereby greatly reducing the stress on the burst groove under cell production, battery pack assembly and vehicle vibration conditions, and preventing the burst groove from fatigue cracking failure due to excessive stress. Attached Figure Description

[0030] The accompanying drawings, which are incorporated in and form part of this specification, illustrate embodiments consistent with this application and, together with the description, serve to explain the principles of this application.

[0031] Figure 1 is a schematic diagram of the explosion-proof valve provided in an embodiment of this application;

[0032] Figure 2 is a cross-sectional view of the explosion-proof valve body provided in the embodiment of this application;

[0033] Figure 3 is an enlarged view of part A in Figure 2;

[0034] Figure 4 is a cross-sectional view of the explosion-proof valve body provided in the embodiment of this application.

[0035] Explanation of reference numerals in the attached figures:

[0036] 100 - Valve body;

[0037] 200-Burning groove.

[0038] The accompanying drawings illustrate specific embodiments of this application, which will be described in more detail below. These drawings and descriptions are not intended to limit the scope of the concept in any way, but rather to illustrate the concept of this application to those skilled in the art through reference to particular embodiments. Detailed Implementation

[0039] To make the objectives, technical solutions, and advantages of this application clearer, the technical solutions of this application will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of this application, not all embodiments. Based on the embodiments of this application, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of this application.

[0040] The terms "first," "second," "third," "fourth," etc. (if present) in the specification, claims, and accompanying drawings of this application are used to distinguish similar objects and are not necessarily used to describe a particular order or sequence. It should be understood that such data can be interchanged where appropriate so that embodiments of the application described herein can be implemented, for example, in orders other than those illustrated or described herein. In embodiments of this application, the words "exemplary" or "for example" are used to indicate examples, illustrations, or descriptions. Any embodiment or design described as "exemplary" or "for example" in this application should not be construed as being more preferred or advantageous than other embodiments or designs. Specifically, the use of the words "exemplary" or "for example" is intended to present the relevant concepts in a concrete manner.

[0041] As mentioned in the background technology: With the continuous development of the battery industry, lithium-ion batteries, with their high energy density, are widely used in the field of power batteries to provide power for vehicle operation.

[0042] The battery includes a battery body, a cover plate, and an explosion-proof valve. The battery body contains battery cells, and the battery body has a receiving cavity for accommodating the cover plate, which is connected to the battery cells. The cover plate is installed in the receiving cavity, and the explosion-proof valve is installed on the cover plate.

[0043] However, under conditions of cell production, battery pack assembly, and vehicle vibration, the stress on the grooves of the explosion-proof valve leads to fatigue cracking and failure, which is quite serious.

[0044] As battery charging speeds increase, the overall battery pack voltage also rises. Higher voltage requires more battery cells. However, the installation space for each battery pack is fixed. To increase the number of cells, the cell thickness needs to be controlled, resulting in thinner cells. The cell thickness determines the width of the cover plate in the battery pack. Because the cells are thinner, the cover plate is narrower, which reduces the installation area of ​​the explosion-proof valve. This reduces the pressure-bearing area of ​​the explosion-proof valve. To maintain a constant opening pressure, the residual thickness of the grooves in the explosion-proof valve needs to be thin, thus affecting the valve's ability to resist stress.

[0045] To address the aforementioned technical problems, this application provides an explosion-proof valve and a battery. The explosion-proof valve is used for installation on a battery and includes a valve body and a burst groove. The thickness of the middle part of the valve body is greater than the thickness of the edge of the valve body. The burst groove is disposed on the valve body and is close to the edge of the valve body. By thickening the middle part of the valve body, this application improves the valve body's ability to resist stress, thereby greatly reducing the stress on the burst groove under conditions of cell production, battery pack assembly, and vehicle vibration, and preventing the burst groove from fatigue cracking failure due to excessive stress.

[0046] The technical solution of this application and how the technical solution of this application solves the above-mentioned technical problems are described in detail below with specific embodiments. These specific embodiments can be combined with each other, and the same or similar concepts or processes may not be described again in some embodiments. The embodiments of this application will now be described with reference to the accompanying drawings.

[0047] Please refer to the following figures: Figure 1 is a structural schematic diagram of the explosion-proof valve provided in the embodiment of this application; Figure 2 is a cross-sectional view of the valve body in the explosion-proof valve provided in the embodiment of this application; Figure 3 is an enlarged view of part A in Figure 2.

[0048] Referring to Figures 1, 2 and 3, this application discloses an explosion-proof valve for installation on a battery, including a valve body 100 and a burst groove 200, wherein the thickness of the middle part of the valve body 100 is greater than the thickness of the edge of the valve body 100.

[0049] The bursting groove 200 is provided on the valve body 100 and is close to the edge of the valve body 100.

[0050] The residual thickness of the valve body 100 at the burst groove 200 is less than the edge thickness of the valve body 100. After the explosion-proof valve is installed on the battery, when the pressure inside the battery reaches the preset pressure, the valve body 100 will crack along the burst groove 200 to release gas and pressure from the battery, thereby avoiding the risk of battery explosion or fire.

[0051] For example, the middle part of the valve body 100 refers to the center position of the valve body 100.

[0052] For example, the length of the same position in the bursting groove 200 from the edge of the valve body 100 is between one-tenth and one-eighth of the length from the center of the valve body 100.

[0053] For example, the valve body 100 is generally stepped, such as a stepped square stack. The thickness of the valve body 100 is the greatest in the middle and the thickness of the valve body 100 is the smallest at the edge. The bursting groove 200 is set at the position of the valve body 100 near the edge and the bursting groove 200 surrounds the valve body 100.

[0054] For example, the valve body 100 is arranged in an isosceles trapezoidal shape. The top surface of the isosceles trapezoid is the middle part of the valve body 100, the bottom edge of the isosceles trapezoid is the edge of the valve body 100, and the bursting groove 200 is located on the inclined surface of the isosceles trapezoid near the bottom edge.

[0055] For example, the cross-section of the bursting groove 200 is an inverted trapezoid. By making the cross-section of the bursting groove 200 an inverted trapezoid, the size of the bottom surface of the groove can be increased, that is, the size of the residual thickness of the bursting groove 200 can be increased, thus ensuring the bursting effect of the bursting groove 200.

[0056] For example, the extension direction of the burst groove 200 is not consistent with the extension direction of the edge of the valve body 100, and the burst groove 200 is arranged in a U-shape or C-shape. Of course, in other embodiments of this application, the burst groove 200 can also be changed to other shapes according to actual needs, without specific limitations.

[0057] By adopting the above technical solution, and by thickening the middle part of the valve body 100, compared with an alternative method where the thickness of the middle part of the valve body 100 is the same as that of the edge, this application thickens the middle part of the valve body 100, which improves the stress resistance of the valve body 100. As a result, under the conditions of cell production, pack assembly and vehicle vibration, the stress on the burst groove 200 is greatly reduced, preventing the burst groove 200 from being subjected to excessive stress and causing fatigue cracking failure.

[0058] The first arrangement of the valve body 100 is disclosed below.

[0059] In some embodiments, the thickness of the valve body 100 gradually decreases from the center to the edge.

[0060] For example, the valve body 100 is generally pyramidal in shape; when the edges of the valve body 100 are quadrilaterals, the valve body 100 is an isosceles quadrangular pyramid. The fixed point of the isosceles quadrangular pyramid is the middle of the valve body 100, the edge of the base of the isosceles quadrangular pyramid is the edge of the valve body 100, and the bursting groove 200 is disposed on the waist surface of the isosceles quadrangular pyramid near the base. Of course, in other embodiments of this application, the valve body 100 can also be changed to other shapes according to actual needs, without specific limitation.

[0061] By adopting the above technical solution, the valve body 100 is configured as a gradually decreasing structure with thickness from the middle to the edge, which not only improves the stress resistance of the valve body 100, but also reduces the production cost of the valve body 100.

[0062] In some embodiments, the side of the valve body 100 where the burst groove 200 is provided is curved.

[0063] For example, the side of the valve body 100 facing away from the burst groove 200 is a plane, so that the valve body 100 as a whole is configured as a convex mirror structure.

[0064] For example, the side of the valve body 100 with the burst groove 200 is a first curved surface, and the side of the valve body 100 away from the burst groove 200 is a second curved surface. The bending direction of the first curved surface can be the same as the bending direction of the second curved surface, or the bending direction of the first curved surface can be opposite to the bending direction of the second curved surface, as long as the thickness of the valve body 100 gradually decreases from the middle to the edge.

[0065] By adopting the above technical solution, by making one side of the valve body 100 with the burst groove 200 curved, the curved surface has a higher stress resistance than the flat surface. This not only further improves the stress resistance of the valve body 100, but also improves the deformation resistance of the middle part of the valve body 100, thus avoiding easy damage to the valve body 100 due to external factors.

[0066] The second arrangement of the valve body 100 is disclosed below.

[0067] Please refer to the following figures: Figure 4 is a cross-sectional view of the explosion-proof valve body provided in the embodiment of this application.

[0068] In some embodiments, referring to FIG4, the valve body 100 has a plurality of stepped surfaces on one side where the burst groove 200 is provided, and the burst groove is located on the outermost stepped surface of the valve body.

[0069] For example, the valve body 100 includes a first stepped surface, a second stepped surface and a third stepped surface connected in sequence. The first stepped surface is located above the second stepped surface, the second stepped surface is located above the third stepped surface, and the area of ​​the first stepped surface is smaller than the area of ​​the second stepped surface, the area of ​​the second stepped surface is smaller than the area of ​​the third stepped surface, and the bursting groove is provided on the third stepped surface.

[0070] The thicknesses of the first step surface, the second step surface, and the third step surface can be the same or different. Of course, in other embodiments of this application, the valve body 100 can also be changed to other shapes according to actual needs without specific limitations.

[0071] By adopting the above technical solution, the valve body 100 has multiple stepped surfaces on one side where the burst groove 200 is provided. The burst groove is located on the outermost stepped surface of the valve body, which improves the stepped arrangement of the valve body 100, thereby making the explosion-proof valve suitable for different batteries.

[0072] For example, each step surface is a plane.

[0073] Alternatively, each step surface can be a slope.

[0074] For example, when the step surface is a plane, the step surface can be cylindrical, frustum-shaped, square columnar, or frustum-shaped, as long as the upper end of the step surface is flat. Of course, in other embodiments of this application, the valve body 100 can also be changed to other shapes according to actual needs without specific limitations.

[0075] For example, when the step surface is inclined, the uppermost step surface is pyramidal or conical, and the lower step surface is frustum or truncated cone. It is only necessary to make the step surface inclined. Of course, in other embodiments of this application, the valve body 100 can also be changed to other shapes according to actual needs without specific limitations.

[0076] By adopting the above technical solution and defining the shape of the stepped surface, the overall shape of the valve body 100 can be defined, thereby making the valve body 100 suitable for different types of batteries.

[0077] In some embodiments, the extending direction of the burst groove 200 is consistent with the extending direction of a portion of the valve body 100 edge.

[0078] For example, the valve body 100 is racetrack-shaped, and the bursting groove 200 is also racetrack-shaped, arranged around the edge of the valve body 100. The racetrack shape has a wide range of applications and can be used with a variety of different batteries. Of course, in other embodiments of this application, the valve body 100 can also be changed to other shapes according to actual needs, without specific limitations.

[0079] By adopting the above technical solution, when the air pressure inside the battery reaches the preset pressure, the valve body 100 bursts at the burst groove 200. The extension direction of the burst groove 200 is consistent with the extension direction of part of the edge of the valve body 100, which can increase the size of the opening after the explosion-proof valve bursts, thereby rapidly releasing the air pressure inside the battery and improving the explosion-proof effect of the explosion-proof valve.

[0080] In some embodiments, the length of the burst groove 200 in the extending direction is at least two-thirds of the circumference of the edge of the valve body 100.

[0081] For example, the burst groove 200 surrounds the valve body 100 near the edge. When a preset pressure value is reached, the burst groove 200 breaks, thereby opening the valve body 100 completely within the slotted portion. This ensures timely pressure relief when the internal air pressure of the battery rises abnormally due to thermal runaway, preventing the battery from exploding.

[0082] For example, the length of the burst groove 200 is four-fifths of the circumference of the valve body 100 near the edge. When the preset pressure value is reached, the burst groove 200 breaks, and the valve body 100 located inside the burst groove 200 opens under the action of the internal air pressure of the battery. At this time, the opened valve body 100 will not detach from the valve body 100, thus preventing the opened valve body 100 from splashing, thereby ensuring the safety of the explosion-proof valve when it bursts.

[0083] By adopting the above technical solution and limiting the length of the burst groove 200, the length of the burst groove 200 can be selected according to different types of batteries, so that the explosion-proof valve can be applied to different batteries.

[0084] In some embodiments, the thickness of the middle portion of the valve body 100 is 2 to 10 times the thickness of the edge portion of the valve body 100.

[0085] For example, the thickness of the middle part of the valve body 100 is between 0.5 mm and 0.7 mm, and the thickness of the edge of the valve body 100 is between 0.05 mm and 0.35 mm.

[0086] By adopting the above technical solution and limiting the thickness of the middle and edge of the valve body 100, the manufacturing cost of the valve body 100 is reduced while ensuring the stress resistance of the valve body 100.

[0087] In some embodiments, the length of the burst groove 200 from the edge of the valve body 100 is between 1 mm and 3 mm, and the residual thickness of the valve body 100 at the burst groove 200 is between 0.03 mm and 0.3 mm.

[0088] For example, the bursting groove 200 is 2 mm long from the edge of the valve body 100.

[0089] For example, the residual thickness of the valve body 100 at the burst groove 200 is 0.1 mm. The residual thickness of the valve body 100 at the burst groove 200 is related to the magnitude of the preset pressure and the area of ​​the bottom surface of the valve body 100. The higher the preset pressure, the thicker the residual thickness of the valve body 100 at the burst groove 200. The lower the preset pressure, the thinner the residual thickness of the valve body 100 at the burst groove 200. The larger the bottom surface area of ​​the valve body 100, the thinner the residual thickness of the valve body 100 at the burst groove 200. The smaller the bottom surface area of ​​the valve body 100, the thicker the residual thickness of the valve body 100 at the burst groove 200.

[0090] By adopting the above technical solution, and by limiting the length of the burst groove 200 from the edge of the valve body 100, sufficient space is ensured on the valve body 100 for welding the valve body 100 to the battery, thus avoiding affecting the airtightness after welding. By limiting the residual thickness of the valve body 100 at the burst groove 200, the explosion-proof valve can be applied to different types of batteries.

[0091] This application also discloses a battery, including a battery body, a cover plate, and any of the explosion-proof valves in the above embodiments. The cover plate has a receiving groove, and the explosion-proof valve is installed in the receiving groove.

[0092] The structure and principle of the explosion-proof valve have been clearly explained in the above embodiments, and will not be elaborated here.

[0093] The explosion-proof valve includes a valve body 100 and a burst groove 200. The thickness of the middle part of the valve body 100 is greater than the thickness of the edge of the valve body 100. The burst groove 200 is provided on the valve body 100 and is close to the edge of the valve body 100.

[0094] The gap between the burst groove 200 and the edge of the valve body 100 is the mounting position of the explosion-proof valve on the cover plate. Under normal circumstances, the length of the burst groove 200 from the edge of the valve body 100 is between 1mm and 3mm, ensuring that there is enough space on the valve body 100 for welding the valve body 100 to the battery, so as to avoid affecting the airtightness after welding.

[0095] The thickness of the valve body 100 can be determined according to the different types of batteries and the battery's operating environment.

[0096] The residual thickness of the valve body 100 at the burst groove 200 is related to the magnitude of the preset pressure and the area of ​​the bottom surface of the valve body 100, so that the explosion-proof valve can be used for different types of batteries.

[0097] The higher the preset pressure, the thicker the residual thickness of the valve body 100 at the burst groove 200; the lower the preset pressure, the thinner the residual thickness of the valve body 100 at the burst groove 200; the larger the bottom area of ​​the valve body 100, the thinner the residual thickness of the valve body 100 at the burst groove 200; the smaller the bottom area of ​​the valve body 100, the thicker the residual thickness of the valve body 100 at the burst groove 200.

[0098] The preset pressure is set in advance based on the maximum pressure value when the battery cells are packaged or when a fire occurs. Under normal circumstances, the preset pressure value is less than the maximum pressure value when the battery cells are packaged or when a fire occurs.

[0099] By adopting the above technical solution, the valve body 100 is thickened in the middle, which improves the valve body 100's ability to resist stress. This greatly reduces the stress on the burst groove 200 under cell production, battery pack assembly, and vehicle vibration conditions, preventing the burst groove 200 from fatigue cracking due to excessive stress.

[0100] The various embodiments or implementation methods described in this specification are presented in a progressive manner. Each embodiment focuses on the differences from other embodiments, and the same or similar parts between the embodiments can be referred to each other.

[0101] It should be noted that the embodiments referred to in the specification, such as "one embodiment," "embodiment," "exemplary embodiment," and "some embodiments," may include specific features, structures, or characteristics, but not every embodiment necessarily includes that specific feature, structure, or characteristic. Furthermore, such phrases do not necessarily refer to the same embodiment. Moreover, when a specific feature, structure, or characteristic is described in connection with an embodiment, implementing such a feature, structure, or characteristic in conjunction with other embodiments, whether explicitly described or not, is within the knowledge scope of those skilled in the art.

[0102] Generally speaking, terms should be understood at least in part by their use in context. For example, at least in part by context, the term "one or more" as used in the text can be used to describe any feature, structure, or characteristic of the singular meaning, or a combination of features, structures, or characteristics of the plural meaning. Similarly, at least in part by context, terms such as "a" or "the" can also be understood to convey either singular or plural usage.

[0103] It should be readily understood that the terms “on,” “above,” and “on top of” in this disclosure should be interpreted in the broadest possible sense, such that “on” means not only “directly on something” but also “on something” with an intermediate feature or layer therebetween, and that “above” or “on top of” means not only “on top of something” but also “on top of something” without an intermediate feature or layer therebetween (i.e., directly on something).

[0104] Furthermore, for ease of explanation, spatially relative terms such as "below," "below," "under," "above," and "above" may be used to describe the relationship of one element or feature relative to other elements or features as shown in the figures. Spatially relative terms are intended to encompass different orientations of the device in use or operation other than those shown in the figures. The device may have other orientations (rotated 90 degrees or in other orientations), and the spatially relative descriptive terms used herein may be interpreted accordingly.

[0105] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of this application, and are not intended to limit them. Although this application has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that modifications can still be made to the technical solutions described in the foregoing embodiments, or equivalent substitutions can be made to some or all of the technical features therein. Such modifications or substitutions do not cause the essence of the corresponding technical solutions to deviate from the scope of the technical solutions of the embodiments of this application.

Claims

1. An explosion-proof valve, configured to be installed on a battery, comprising: The valve body and the bursting groove, wherein the thickness of the middle part of the valve body is greater than the thickness of the edge of the valve body; The bursting groove is disposed on the valve body and is located near the edge of the valve body.

2. The explosion-proof valve according to claim 1, wherein: The thickness of the valve body gradually decreases from the middle to the edge.

3. The explosion-proof valve according to claim 2, wherein: The side of the valve body where the bursting groove is located is curved.

4. The explosion-proof valve according to claim 1, wherein: The valve body has multiple stepped surfaces on one side where the bursting groove is provided, and the bursting groove is located on the outermost stepped surface of the valve body.

5. The explosion-proof valve according to claim 4, wherein: Each of the aforementioned step surfaces is a plane; Alternatively, each of the step surfaces may be a ramp.

6. The explosion-proof valve according to any one of claims 1-5, wherein: The direction of the bursting groove is consistent with the direction of the extension of part of the valve body edge.

7. The explosion-proof valve according to claim 6, wherein: The length of the bursting groove in the extending direction is at least two-thirds of the circumference of the edge of the valve body.

8. The explosion-proof valve according to any one of claims 1-5, wherein: The thickness of the middle part of the valve body is 2 to 10 times the thickness of the edge of the valve body.

9. The explosion-proof valve according to any one of claims 1-5, wherein: The distance between the bursting groove and the edge of the valve body is between 1 mm and 3 mm, and the residual thickness of the valve body at the bursting groove is between 0.03 mm and 0.3 mm.

10. A battery, comprising: The battery body, the cover plate, and the explosion-proof valve according to any one of claims 1-9, wherein the cover plate has a receiving groove, and the explosion-proof valve is installed in the receiving groove.

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