Explosion-proof valve, cover plate, cover plate assembly and battery cell

Abstract

This application provides an explosion-proof valve, a cover plate, a cover plate assembly, and a battery cell. The explosion-proof valve includes a valve body with a first surface. A first notch and a second notch are formed on the first surface. The first notch is annular, and a portion of the first notch protrudes outward or inward along the radial direction of the first notch to form a deformation notch. The second notch is located on the side of the deformation notch away from the first notch and communicates with the deformation notch. By forming a deformation notch by partially protruding or inwardly setting the first notch, and by setting the second notch on the deformation notch, this application increases the stress concentration at the deformation notch of the explosion-proof valve. This allows the explosion-proof valve to break open first at the deformation notch, and then continue to tear along the first notch from the initial breakage point to form an exhaust channel. This reduces the difficulty of setting the notch on the cover plate, increases the stability of the battery cell's valve opening, and thus improves the safety and reliability of the battery cell.

Description

Technical Field

[0001] This application relates to the field of battery technology, specifically to an explosion-proof valve, a cover plate, a cover plate assembly, and a battery cell. Background Technology

[0002] A battery cell consists of a casing, terminals extending through the casing, and electrode assemblies and electrolyte disposed within the casing. During charging and discharging, if overcharging, over-discharging, or short circuits occur, a large amount of gas will be generated inside the cell. This gas rapidly accumulates inside the sealed cell, causing a sharp increase in internal pressure. When the internal pressure exceeds the casing's withstand limit, the cell may explode, generating high-temperature fragments and a shock wave. Therefore, an explosion-proof valve needs to be installed on the cell casing. When the internal pressure reaches the valve's threshold, it opens to release the gas inside the cell, thus alleviating the internal pressure and preventing the casing from exploding.

[0003] In related technologies, grooves are set on the outer casing as explosion-proof valves for the battery cell. The grooves create a weak point in the casing. When the internal pressure of the battery cell reaches a preset threshold, the groove will rupture first, forming an exhaust channel on the casing and releasing the gas inside the battery cell.

[0004] During normal use of the battery cell, the casing needs to have reliable compressive strength at the scored areas. However, when the internal pressure of the battery cell is too high, the casing needs to be able to break first at the scored areas, allowing the casing to respond promptly to the need for venting and depressurization. This makes it difficult to control the size of the scored areas and results in poor stability of the battery cell's valve opening, thus reducing the reliability of the battery cell. Utility Model Content

[0005] The embodiments of this application provide an explosion-proof valve, a cover plate, a cover plate assembly, and a battery cell, which can reduce the difficulty of setting the scoring on the cover plate, increase the stability of the battery cell opening valve, and thus improve the safety and reliability of the battery cell.

[0006] In a first aspect, embodiments of this application provide an explosion-proof valve, which includes a valve body having a first surface. A first notch and a second notch are provided on the first surface. The first notch is annular, and a portion of the first notch convexes outward or concave inward along its radial direction to form a deformation notch. The second notch is located on the side of the deformation notch away from the first notch, and the second notch communicates with the deformation notch. This increases stress concentration at the deformation notch, allowing the explosion-proof valve to break open first at the deformation notch, and then continue tearing along the first notch from the initial breakage point to form an exhaust channel. This reduces the difficulty of setting the notch on the cover plate, increasing the stability of the battery cell's valve opening and thus improving the safety and reliability of the battery cell.

[0007] In some embodiments, a portion of the first notch protrudes outward along the first surface to form a deformation notch. This allows the explosion-proof valve to have a larger flat surface within the area enclosed by the first notch, which facilitates the placement of structures such as electrode posts and injection holes within the area enclosed by the first notch when using an explosion-proof valve in the battery cell, thereby reducing the difficulty of battery cell arrangement.

[0008] In some embodiments, the second notch extends in an arc shape on the first surface, with the center of the second notch located on the side of the second notch away from the deformation notch. Thus, while maintaining a fixed distance between the two ends of the second notch, the length of the second notch can be increased to increase the stress concentration of the explosion-proof valve at the deformation notch.

[0009] In some embodiments, the middle portion of the second notch is connected to the deformation notch. This improves the symmetry of the arrangement of the second notch relative to the deformation notch, thereby enhancing the aesthetics of the explosion-proof valve.

[0010] In some embodiments, the distance between the connection point between the deformation groove and the second groove and the end of the second groove is L1, satisfying: 1mm≤L1≤10mm. This avoids the second groove from becoming too long, which would reduce the structural strength of the explosion-proof valve, while ensuring the basic length of the second groove, thus improving machinability and manufacturing efficiency of the explosion-proof valve.

[0011] In some embodiments, the first notch is a circular annular structure. This allows the first notch to be positioned and processed based on a common center, thereby improving the efficiency of the first notch forming.

[0012] In some embodiments, the radius of the first notch is R1, and the distance from the center of the deformation notch to the center of the first notch is R2, satisfying: 0.5mm ≤ R2 - R1 ≤ 5mm. This ensures the basic protrusion length of the deformation notch, improving machinability and manufacturing efficiency of the explosion-proof valve, while preventing excessively large protrusions from affecting the arrangement of the battery cell in other structures surrounding the explosion-proof valve, thus reducing the difficulty of battery cell placement.

[0013] In some embodiments, on the first surface, the deformation groove has a span dimension B1 perpendicular to its own protrusion direction, and the diameter of the first groove is D1, satisfying: 20%D1≤B1≤40%D1. This ensures the basic width dimension of the deformation groove, which improves machinability and manufacturing efficiency of the explosion-proof valve; it also avoids excessively large deformation groove widths that would result in insufficient stress concentration at the deformation groove location in the explosion-proof valve.

[0014] In some embodiments, there are multiple deformation grooves, and the number of second grooves is the same as the number of deformation grooves, with each deformation groove corresponding to a different second groove. This allows the explosion-proof valve to have multiple stress concentration points, enabling it to break first through the multiple deformation grooves, and then simultaneously tear along the first groove located between the deformation grooves. This disconnects the portion of the explosion-proof valve enclosed by the first groove from the valve, increasing the venting area and improving the pressure relief rate.

[0015] In some embodiments, the deformation grooves are evenly distributed at circumferential intervals along the first groove. This improves the synchronicity of tearing at the locations between the deformation grooves, facilitating rapid opening of the explosion-proof valve for venting and depressurization, and also enhances the aesthetics of the explosion-proof valve.

[0016] Secondly, embodiments of this application provide a cover plate comprising a cover body and the aforementioned explosion-proof valve; the valve body is disposed on the cover body; wherein the cover body and the valve body are sealed together, or the cover body and the valve body are integrally formed. This increases the stress concentration at the deformation groove of the explosion-proof valve, thereby allowing the explosion-proof valve to break open first at the deformation groove, and continue to tear along the first groove from the initial breakage point to form an exhaust channel. This reduces the difficulty of setting the grooves on the cover plate, increasing the stability of the cell's valve opening, thereby improving the safety and reliability of the cell.

[0017] Thirdly, embodiments of this application provide a cover plate assembly including the aforementioned cover plate. This increases stress concentration at the deformation groove of the explosion-proof valve, allowing the valve to break open first at the deformation groove and continue tearing along the first groove from the initial breakage point, forming an exhaust channel. This reduces the difficulty of setting the cover plate groove, increasing the stability of the cell's valve opening and thus improving the cell's safety and reliability.

[0018] Fourthly, embodiments of this application provide a battery cell comprising a housing, an electrode assembly, and the aforementioned cover assembly; the electrode assembly is disposed within the housing; the cover assembly is fitted to the housing. This increases stress concentration at the deformation groove of the explosion-proof valve, allowing the valve to break open first at the deformation groove, and then continue tearing along the first groove from the initial breakage point to form an exhaust channel. This reduces the difficulty of setting the cover groove, increasing the stability of the battery cell's valve opening and thus improving the battery cell's safety and reliability.

[0019] In some embodiments, the battery cell is a cylindrical cell with an outer diameter of D and a diameter of D1 for the first notch, satisfying: 30%D≤D1≤85%D. This design allows for a larger venting channel to be formed when the explosion-proof valve breaks at the first notch, improving the efficiency of venting and depressurizing the battery cell. It also prevents the explosion-proof valve from affecting the connection between the cover plate and the housing, ensuring the connection strength between the cover plate and the housing and improving the reliability of the battery cell.

[0020] The beneficial effects of the embodiments of this application are as follows:

[0021] In the embodiments of this application, by partially convex or concave of the first notch to form a deformation notch, and then providing a second notch on the deformation notch, the stress concentration at the deformation notch of the explosion-proof valve can be increased. This allows the explosion-proof valve to break open first at the deformation notch, and then continue to tear along the first notch from the initial breakage point to form an exhaust channel. This reduces the difficulty of setting the notch on the cover plate, increases the stability of the cell's valve opening, and thus improves the safety and reliability of the cell. Attached Figure Description

[0022] To more clearly illustrate the technical solutions in the embodiments of this application, the accompanying drawings used in the description of the embodiments will be briefly introduced below. Obviously, the accompanying drawings described below are only some embodiments of this application. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0023] Figure 1 This is a schematic diagram of the battery cell structure provided in an embodiment of this application;

[0024] Figure 2 This is a schematic diagram of the internal structure of the battery cell provided in an embodiment of this application;

[0025] Figure 3 This is a schematic diagram of the structure of the cover plate assembly provided in an embodiment of this application;

[0026] Figure 4 This is a schematic diagram of the structure of the cover plate provided in an embodiment of this application;

[0027] Figure 5 This is a schematic diagram of the structure of the explosion-proof valve provided in an embodiment of this application;

[0028] Figure 6 yes Figure 5 An enlarged schematic diagram of part A in the middle;

[0029] Figure 7 yes Figure 5 A cross-sectional view of BB.

[0030] Explanation of reference numerals in the attached figures:

[0031] 1000-cell;

[0032] 100 - Cover plate assembly;

[0033] 10-Explosion-proof valve; 11-First surface; 111-First notch; 112-Second notch; 113-Deformation notch; 12-Valve body;

[0034] 20-Cover plate; 21-Annular protrusion; 22-Annular groove; 23-Injection hole; 24-Sunken platform; 25-Sealing aluminum sheet; 26-Sealing nail; 27-Cover body;

[0035] 30 - Housing; 40 - Electrode assembly. Detailed Implementation

[0036] The technical solutions of the embodiments 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, and 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.

[0037] Furthermore, it should be understood that the specific embodiments described herein are for illustrative and explanatory purposes only and are not intended to limit the scope of this application. In this application, the terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of indicated technical features. Thus, features defined with "first" and "second" may explicitly or implicitly include one or more of the stated features. In the description of this application, "a plurality of" means two or more, unless otherwise explicitly specified.

[0038] In the description of this application, it should be noted that, unless otherwise expressly specified and limited, the terms "installation," "connection," and "joining" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral connection; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium; they can refer to the internal communication of two components or the interaction between two components. Those skilled in the art can understand the specific meaning of the above terms in this application according to the specific circumstances.

[0039] The terms “comprising,” “including,” or any other variations thereof are intended to cover non-exclusive inclusion, such that a product that comprises a list of elements includes not only those elements but also other elements not expressly listed or inherent to such a product.

[0040] The following combination Figures 1 to 7 The following is a detailed description of the explosion-proof valve 10, cover plate 20, cover plate assembly 100 and battery cell 1000 provided in the embodiments of this application.

[0041] An embodiment of this application provides a battery cell 1000, which includes a housing 30, an electrode assembly 40, and a cover plate assembly 100. The electrode assembly 40 is disposed within the housing 30. The cover plate 20 of the cover plate assembly 100 covers the housing 30.

[0042] Please see Figure 1 and Figure 2 The battery cell 1000 mentioned in the embodiments of this application may include lithium-ion secondary batteries, lithium-ion primary batteries, lithium-sulfur batteries, sodium-lithium-ion batteries, sodium-ion batteries, or magnesium-ion batteries, etc., and the embodiments of this application are not limited to these. The battery cell 1000 may be cylindrical, flat, cuboid, or other shapes, etc., and the embodiments of this application are not limited to these. The battery cell 1000 is generally divided into three types according to the packaging method: cylindrical battery cells, square battery cells, and pouch battery cells, and the embodiments of this application are not limited to these.

[0043] For example, cell 1000 is a cylindrical cell 1000. Specifically, cell 1000 is a cylindrical steel-cased cell 1000. Correspondingly, casing 30 is a steel casing.

[0044] It is understood that the battery cell 1000 may also include a current collector, terminals, an upper plastic component, a lower plastic component, and a sealing ring, etc. When the battery cell 1000 is a cylindrical steel-cased battery cell 1000, the outer casing of the battery cell 1000 may include a cover plate assembly 100, a steel shell, a top cover, a rubber ring, and a perforated plate, etc. The rubber ring is clamped between one end of the steel shell and the top cover to seal the steel shell and the top cover. The perforated plate connects the positive electrode tab of the electrode assembly 40 to the top cover. The negative electrode tab of the electrode assembly 40 is connected to the steel shell and / or the cover plate assembly 100.

[0045] The housing 30 houses the electrode assembly 40 and the electrolyte. The electrode assembly 40 consists of a positive electrode, a separator, and a negative electrode stacked sequentially. The separator insulates and isolates the positive and negative electrodes and provides channels for metal ions to pass through. The cell 1000 primarily stores or releases electrical energy by moving metal ions between the positive and negative electrodes. The positive electrode includes a positive current collector and a positive active material layer. The positive active material layer is coated on the surface of the positive current collector, and the uncoated positive current collector serves as the positive electrode tab. Taking a lithium-ion battery as an example, the positive current collector can be made of aluminum, and the positive active material can be lithium cobalt oxide, lithium iron phosphate, ternary lithium, or lithium manganese oxide, etc. The negative electrode includes a negative current collector and a negative active material layer. The negative active material layer is coated on the surface of the negative current collector, and the uncoated negative current collector serves as the negative electrode tab. The negative electrode current collector can be made of copper, and the negative electrode active material can be carbon or silicon, etc. To ensure that a large current can be passed without melting, there are multiple positive electrode tabs stacked together, and there are multiple negative electrode tabs stacked together.

[0046] Please see Figure 3 This application provides a cover plate assembly 100, which includes a cover plate 20. It is understood that the cover plate assembly 100 may include a sealing aluminum sheet 25 and a sealing nail 26. An injection hole 23 and a recessed platform 24 are provided on the cover plate 20. The recessed platform 24 is located at the end of the injection hole 23 opposite to the electrode assembly 40. The bottom of the recessed platform 24 communicates with the injection hole 23. Electrolyte is injected into the battery cell 1000 through the injection hole 23. The sealing nail 26 seals the injection hole 23, and the sealing aluminum sheet 25 is welded to the recessed platform 24, sealing the platform 24.

[0047] Please see Figure 4 An embodiment of this application provides a cover plate 20, which includes a cover body 27 and the aforementioned explosion-proof valve 10. The valve body 12 is disposed on the cover body 27. The cover body 27 and the valve body 12 are either sealed together or integrally formed.

[0048] It is understood that the cover 27 may have a mounting through hole, the valve body 12 is disposed in the mounting through hole, and the first surface 11 is located at one end of the mounting through hole. In this case, the cover 20 and the valve body 12 can be welded to achieve a sealed connection.

[0049] It is understandable that the cover plate 20 can be integrally set with the valve body 12, and grooves can be machined on the cover plate 20 to define the explosion-proof valve 10.

[0050] For example, the first surface 11 is located on the side of the cover plate 20 opposite to the electrode assembly 40.

[0051] For example, the cover 27 is provided with a plurality of annular protrusions 21, which protrude into the interior of the battery cell 1000 to form an annular groove 22 on the surface of the cover plate 20 opposite to the battery cell 1000. In this way, a plurality of reinforcing ribs can be formed on the cover 27 to improve the structural strength of the cover plate 20.

[0052] Please see Figure 5 and Figure 6 This application provides an explosion-proof valve 10. The explosion-proof valve 10 includes a valve body 12, which has a first surface 11. A first notch 111 and a second notch 112 are provided on the first surface 11. The first notch 111 is annular. A portion of the first notch 111 convexes outward or concave inward along its radial direction to form a deformation notch 113. The second notch 112 is located on the side of the deformation notch 113 away from the first notch 111. The second notch 112 communicates with the deformation notch 113.

[0053] It is understood that grooves are machined into the valve body 12 to form the first notch 111 and the second notch 112, such as... Figure 7As shown. The width of the groove opening is greater than the width of the groove bottom, and the width of the groove bottom is greater than 0, in order to avoid excessive stress at the groove bottom and reduce the structural strength of the explosion-proof valve 10.

[0054] It is understood that the first notch 111 can be a circular ring structure, an oval ring structure, or a rectangular ring structure. Specifically, the first notch 111 extends along the periphery of the cover plate 20 on which the explosion-proof valve 10 is provided.

[0055] The first notch 111 may be partially recessed along the first surface 11 to form a deformed notch 113, or a portion of the first notch 111 may be partially convex along the first surface 11 to form a deformed notch 113.

[0056] In this embodiment, by partially protruding or concave of the first notch 111 to form a deformation notch 113, and by providing a second notch 112 on the deformation notch 113, the stress concentration of the explosion-proof valve 10 at the deformation notch 113 can be increased. This allows the explosion-proof valve 10 to break open first at the deformation notch 113, and then continue to tear along the first notch 111 from the point of initial breakage, forming an exhaust channel. This reduces the difficulty of setting the notches on the cover plate 20, increases the stability of the valve opening of the battery cell 1000, and thus improves the safety and reliability of the battery cell 1000.

[0057] Please see Figure 5 In some embodiments, a portion of the first notch 111 protrudes outward along the first surface 11 to form a deformable notch 113. This allows the explosion-proof valve 10 to have a larger plane within the area enclosed by the first notch 111, which is beneficial when the battery cell 1000 uses the explosion-proof valve 10, allowing for the placement of structures such as poles and injection holes 23 within the area enclosed by the first notch 111, thereby reducing the difficulty of arranging the battery cell 1000.

[0058] In some embodiments, the second notch 112 extends in an arc shape on the first surface 11, and the center of the second notch 112 is located on the side of the second notch 112 away from the deformation notch 113. In this way, the length of the second notch 112 can be increased while maintaining a certain distance between the two ends of the second notch 112, so as to increase the stress concentration of the explosion-proof valve 10 at the deformation notch 113.

[0059] In other embodiments, the second notch 112 extends in a V-shape on the first surface 11, and the corner of the second notch 112 is connected to the deformed notch 113. Alternatively, the second notch 112 is a straight line extending on the first surface 11, and the deformed notch 113 is tangent to the second notch 112.

[0060] Please see Figure 6In some embodiments, the middle portion of the second notch 112 is connected to the deformation notch 113. This improves the symmetry of the arrangement of the second notch 112 relative to the deformation notch 113, thereby enhancing the aesthetics of the explosion-proof valve 10.

[0061] Please see Figure 6 In some embodiments, the distance between the connection between the deformation groove 113 and the second groove 112 and the end of the second groove 112 is L1, which satisfies: 1mm≤L1≤10mm.

[0062] It is understood that the distance L1 between the connection between the deformation groove 113 and the second groove 112 and the end of the second groove 112 is, but is not limited to, 1mm, 1.3mm, 1.6mm, 1.9mm, 2.2mm, 2.5mm, 2.8mm, 3.1mm, 3.4mm, 3.7mm, 4.0mm, 4.3mm, 4.6mm, 4.9mm, 5.2mm, 5.5mm, 5.8mm, 6.1mm, 6.4mm, 6.7mm, 7.0mm, 7.3mm, 7.6mm, 7.9mm, 8.2mm, 8.5mm, 8.8mm, 9.1mm, 9.4mm, 9.7mm, and 10mm.

[0063] In this embodiment, by limiting the distance L1 between the connection part between the deformation groove 113 and the second groove 112 and the end of the second groove 112, on the one hand, the excessive length of the second groove 112 can be avoided, which would reduce the structural strength of the explosion-proof valve 10; on the other hand, the basic length of the second groove 112 can be guaranteed, which is conducive to improving machinability and increasing the manufacturing efficiency of the explosion-proof valve 10.

[0064] Please see Figure 5 In some embodiments, the first notch 111 is a circular annular structure. This allows the first notch 111 to be positioned and processed based on the same center, thereby improving the forming efficiency of the first notch 111.

[0065] For example, the center of the first notch 111 coincides with the center of the cover plate 20 on which the explosion-proof valve 10 is provided on the battery cell 1000.

[0066] Please see Figure 5 In some embodiments, the radius of the first notch 111 is R1. The distance between the deformed notch 113 and the center of the first notch 111 is R2, satisfying: 0.5mm≤R2-R1≤5mm.

[0067] It is understandable that 0.5mm to 5mm is the size of the deformation mark 113 protruding relative to the first mark 111.

[0068] It is understood that the dimensions of the deformation notch 113 protruding relative to the first notch 111 include, but are not limited to, 0.5mm, 0.6mm, 0.8mm, 1mm, 1.2mm, 1.4mm, 1.6mm, 1.8mm, 2mm, 2.2mm, 2.4mm, 2.6mm, 2.8mm, 3mm, 3.2mm, 3.4mm, 3.6mm, 3.8mm, 3.9mm, 4mm, 4.1mm, 4.2mm, 4.3mm, 4.4mm, 4.5mm, 4.6mm, 4.7mm, 4.8mm, 4.9mm, and 5mm.

[0069] In this embodiment, the above-mentioned limitations can, on the one hand, ensure the basic protrusion length of the deformation mark 113, thereby improving machinability and manufacturing efficiency of the explosion-proof valve 10; on the other hand, prevent the protrusion size of the deformation mark 113 from being too large and affecting the arrangement of other structures around the battery cell 1000, thereby reducing the difficulty of arranging the battery cell 1000.

[0070] Please see Figure 5 In some embodiments, in the first surface 11, the deformation notch 113 has a span dimension B1 perpendicular to its own protrusion direction, and the diameter of the first notch 111 is D1, satisfying: 20%D1≤B1≤40%D1.

[0071] It is understood that the span size B1 of the deformation notch 113 includes, but is not limited to, 20% D1, 20.7% D1, 21.4% D1, 22.1% D1, 22.8% D1, 23.5% D1, 24.2% D1, 24.9% D1, 25.6% D1, 26.3% D1, 27.0% D1, 27.7% D1, 28.4% D1, and 29%. 1%D1, 29.8%D1, 30.5%D1, 31.2%D1, 31.9%D1, 32.6%D1, 33.3%D1, 34.0%D1, 34.7 %D1, 35.4%D1, 36.1%D1, 36.8%D1, 37.5%D1, 38.2%D1, 38.9%D1, 39.6%D1, 40%D1.

[0072] In this embodiment, by limiting the width dimension B1 of the deformation groove 113, on the one hand, the basic width dimension of the deformation groove 113 can be guaranteed, which is conducive to improving machinability and improving the manufacturing efficiency of the explosion-proof valve 10; on the other hand, it can avoid the deformation groove 113 being too large and the stress concentration at the deformation groove 113 of the explosion-proof valve 10 being not obvious.

[0073] Please see Figure 5In some embodiments, there are multiple deformation grooves 113. The number of second grooves 112 is the same as the number of deformation grooves 113. Each deformation groove 113 corresponds one-to-one with a number of second grooves 112. This allows the explosion-proof valve 10 to have multiple stress concentration points, facilitating the initial rupture of the explosion-proof valve 10 through the multiple deformation grooves 113, followed by simultaneous tearing along the portion of the first groove 111 located between the deformation grooves 113. This disconnects the portion of the explosion-proof valve 10 enclosed by the first groove 111 from the explosion-proof valve 10, increasing the venting area and improving the pressure relief rate of the explosion-proof valve 10.

[0074] For example, there are four deformation marks 113 and four second marks 112, and the first mark 111 is a circular ring structure. The four deformation marks 113 are centrally symmetrically distributed around the center of the first mark 111.

[0075] Please see Figure 5 In some embodiments, the deformation grooves 113 are evenly distributed at circumferential intervals along the first groove 111. This improves the synchronicity of tearing of the portion of the first groove 111 located between the deformation grooves 113, facilitating the rapid opening of the explosion-proof valve 10 for venting and depressurization, and also enhances the aesthetics of the explosion-proof valve 10.

[0076] Please see Figure 2 In some embodiments, the battery cell 1000 is a cylindrical battery cell 1000, the outer diameter of the battery cell 1000 is D, and the diameter of the first notch 111 is D1, satisfying: 30%D≤D1≤85%D.

[0077] It is understood that the diameter D1 of the first notch 111 includes, but is not limited to, 30% D1, 31.9% D1, 33.8% D1, 35.7% D1, 37.6% D1, 39.5% D1, 41.4% D1, 43.3% D1, 45.2% D1, 47.1% D1, 49.0% D1, 50.9% D1, 52.8% D1, and 54.7%. %D1, 56.6%D1, 58.5%D1, 60.4%D1, 62.3%D1, 64.2%D1, 66.1%D1, 68.0%D1, 69.9% D1, 71.8% D1, 73.7% D1, 75.6% D1, 77.5% D1, 79.4% D1, 81.3% D1, 83.2% D1, 85% D1.

[0078] In this embodiment, the above-mentioned limitations allow for the formation of a larger exhaust channel when the explosion-proof valve 10 breaks at the first notch 111, thereby improving the efficiency of the battery cell 1000 in venting and depressurizing. On the other hand, the installation of the explosion-proof valve 10 can prevent it from affecting the connection between the cover plate 20 and the housing 30, thus ensuring the connection strength between the cover plate 20 and the housing 30 and improving the reliability of the battery cell 1000.

[0079] The embodiments of this application have been described in detail above. Specific examples have been used to illustrate the principles and implementation methods of this application. The description of the above embodiments is only for the purpose of helping to understand the method and core ideas of this application. At the same time, for those skilled in the art, there will be changes in the specific implementation methods and application scope based on the ideas of this application. Therefore, the content of this specification should not be construed as a limitation of this application.

Claims

1. An explosion-proof valve (10), characterized in that, Includes a valve body (12), the valve body (12) having a first surface (11), on which: The first notch (111) is annular, and a portion of the first notch (111) convexes outward or concave inward along the radial direction of the first notch (111) to form a deformed notch (113); and The second notch (112) is located on the side of the deformed notch (113) away from the first notch (111), and the second notch (112) is connected to the deformed notch (113).

2. The explosion-proof valve (10) according to claim 1, characterized in that, A portion of the first notch (111) protrudes outward along the first surface (11) to form the deformation notch (113).

3. The explosion-proof valve (10) according to claim 2, characterized in that, The second groove (112) extends in an arc shape on the first surface (11), and the center of the second groove (112) is located on the side of the second groove (112) away from the deformed groove (113).

4. The explosion-proof valve (10) according to claim 3, characterized in that, The middle part of the second notch (112) is connected to the deformation notch (113).

5. The explosion-proof valve (10) according to claim 3, characterized in that, The distance between the connection between the deformation groove (113) and the second groove (112) and the end of the second groove (112) is L1, which satisfies: 1mm≤L1≤10mm.

6. The explosion-proof valve (10) according to any one of claims 2-5, characterized in that, The first notch (111) is a circular ring structure.

7. The explosion-proof valve (10) according to claim 6, characterized in that, The radius of the first notch (111) is R1, and the distance between the deformed notch (113) and the center of the first notch (111) is R2, satisfying: 0.5mm≤R2-R1≤5mm.

8. The explosion-proof valve (10) according to claim 6, characterized in that, In the first surface (11), the deformation groove (113) has a span dimension B1 perpendicular to its own protrusion direction, and the diameter of the first groove (111) is D1, satisfying: 20%D1≤B1≤40%D1.

9. The explosion-proof valve (10) according to any one of claims 1-5, characterized in that, There are multiple deformation marks (113), the number of second marks (112) is the same as the number of deformation marks (113), and the multiple deformation marks (113) correspond one-to-one with the multiple second marks (112).

10. The explosion-proof valve (10) according to claim 9, characterized in that, The deformation marks (113) are evenly distributed at circumferential intervals along the first mark (111).

11. A cover plate (20), characterized in that, include: Cover (27); as well as The explosion-proof valve (10) as described in any one of claims 1-10, wherein the valve body (12) is disposed on the cover (27); The cover (27) is sealed to the valve body (12), or the cover (27) and the valve body (12) are integrally formed.

12. A cover plate assembly (100), characterized in that, Includes the cover plate (20) as described in claim 11.

13. A battery cell (1000), characterized in that, include: Shell (30); An electrode assembly (40) is disposed within the housing (30); as well as The cover plate assembly (100) as claimed in claim 12, wherein the cover plate (20) covers the housing (30).

14. The battery cell (1000) according to claim 13, characterized in that, The battery cell (1000) is a cylindrical battery cell (1000), the outer diameter of the battery cell (1000) is D, and the diameter of the first notch (111) is D1, satisfying: 30%D≤D1≤85%D.

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