Explosion-proof valve and battery
By designing the explosion-proof valve with a thickness greater in the middle than at the ends, and varying it in one or more directions, the problem of premature valve opening caused by the weak middle part of the explosion-proof valve is solved, thus improving the stability and lifespan of the battery.
Patent Information
- Application Number
- CN202422864260.5
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- Filing Date
- 2024-11-22
- Publication Date
- 2025-12-30
- Estimated Expiration
- 2034-11-22
AI Technical Summary
Existing explosion-proof valves are thinner in the middle due to their increased size in batteries, making them prone to premature opening before the preset opening pressure is reached, affecting the explosion accuracy and the long-term stability of the battery.
The explosion-proof valve is designed with a thickness greater in the middle than at the ends, and the thickness gradually decreases or increases along one or more directions to enhance the strength of the middle section and ensure uniform valve opening pressure.
It improves the bursting accuracy of the explosion-proof valve, extends the battery's lifespan and stability, and prevents premature valve opening.
Smart Images
Figure CN223743835U_ABST
Abstract
Description
TECHNICAL FIELD
[0001] The utility model relates to the technical field of explosion-proof valve, especially to an explosion-proof valve and battery. BACKGROUND
[0002] In recent years, the market share of electric vehicles is increasing, and the market of power batteries is also expanding. The development of the industry requires power batteries to have better performance, and higher requirements for the long-term safety of the battery. Please refer to Figure 1 , Figure 1 For the existing battery, the battery usually includes a shell 1, a top cover 2 and a battery cell, wherein the battery cell is accommodated in the shell 1, the top cover 2 seals the opening of the shell 1 and leads out the electrode of the battery cell, so as to charge or discharge the internal battery cell, and the current battery mostly sets an explosion-proof hole 211 on the top cover 2 and sets an explosion-proof valve 3 at the explosion-proof hole 211, the explosion-proof valve 3 plays an important role in the safety of the battery, when the battery temperature exceeds a certain threshold, the current is too large or the internal pressure abnormally increases, the explosion-proof valve 3 will automatically open, release the internal gas and heat, thereby effectively preventing the battery from overheating, overcharging, overvoltage and other dangerous conditions. In the process of battery package design, because the support beam and the layout of the circuit inside the box are relatively fixed, the thickness T and the height H of the battery are usually limited, in order to improve the energy density of the battery package, the current way is mostly to increase the length size W of the battery, the larger the length size W of the battery, the fewer the number of batteries arranged in the same row in the battery package, and the higher the space utilization rate inside the battery package. Due to the limitation of the thickness T of the battery, in order to improve the opening area of the explosion-proof valve 3, the size of the current explosion-proof valve 3 is also increased with the increase of the length W of the battery. When the size of the explosion-proof valve 3 is increased, the middle position of the explosion-proof valve 3 is relatively weak due to large deformation, so that the middle part of the explosion-proof valve 3 is broken when the internal gas pressure of the battery does not reach the preset opening pressure, which causes the explosion-proof valve 3 to open prematurely, which greatly affects the explosion accuracy of the explosion-proof valve 3. SUMMARY
[0003] The utility model provides a kind of explosion-proof valve and battery, mainly solve the technical problem of explosion-proof valve in prior art opens valve in advance.
[0004] To achieve the above object, the utility model provides the following technical scheme:
[0005] An explosion-proof valve, the explosion-proof valve includes explosion-proof middle part and explosion-proof end, the thickness of the explosion-proof middle part is greater than the thickness of the explosion-proof end.
[0006] In one of the technical solutions, the thickness of the explosion-proof middle part decreases in a gradient along the direction from the explosion-proof middle part to the explosion-proof end; and / or, the thickness of the explosion-proof end increases in a gradient along the direction from the explosion-proof end to the explosion-proof middle part.
[0007] In one of the technical solutions, the thickness of the explosion-proof valve decreases gradually along the direction from the explosion-proof middle part to the explosion-proof end part.
[0008] In one of the technical solutions, the thickness of the thinnest area of the explosion-proof end part is 0.6-0.95 times the thickness of the thickest area of the explosion-proof middle part.
[0009] In one of the technical solutions, the explosion-proof middle part accounts for 60%-90% of the length of the explosion-proof valve in the first direction; and / or, the explosion-proof end part accounts for 5%-20% of the length of the explosion-proof valve in the first direction.
[0010] In one of the technical solutions, the explosion-proof valve comprises a main part and a glue layer arranged on the surface of the main part, and the main part is arranged with equal thickness.
[0011] In one of the technical solutions, the explosion-proof valve is integrally formed.
[0012] The application also provides a battery comprising a shell and a battery cell, wherein the shell forms a containing cavity, the battery cell is arranged in the containing cavity, and the shell comprises the explosion-proof valve.
[0013] In one of the technical solutions, the distance from the side surface of the explosion-proof valve close to the battery cell to the battery cell gradually increases along the direction from the explosion-proof middle part to the explosion-proof end part; and / or, the distance from the side surface of the explosion-proof valve far from the battery cell to the battery cell gradually decreases along the direction from the explosion-proof middle part to the explosion-proof end part.
[0014] In one of the technical solutions, the shell comprises a shell body and a top cover, and the explosion-proof valve is arranged on the top cover; in the length direction of the top cover, the length a of the explosion-proof valve accounts for 0.1-0.3 of the length A of the top cover; and / or, in the width direction of the top cover, the width b of the explosion-proof valve accounts for 0.4-0.8 of the width B of the top cover.
[0015] Compared with the prior art, the explosion-proof valve has at least the following beneficial effects:
[0016] The explosion-proof middle part has a thickness greater than that of the explosion-proof end part, so that the strength of the explosion-proof middle part is strengthened relative to the explosion-proof end part, the opening pressure of the explosion-proof valve at different positions is uniform, the explosion-proof valve is prevented from opening prematurely before reaching the preset opening pressure, the explosion accuracy of the explosion-proof valve is improved, the stability of the battery during long-term use is improved, and the service life of the battery is prolonged. BRIEF DESCRIPTION OF DRAWINGS
[0017] In order to more clearly illustrate the technical solutions of the embodiments of the present application or the prior art, the following will briefly introduce the drawings needed to be used in the embodiments or the prior art description. Obviously, the drawings described below are only some embodiments of the present application, and for those skilled in the art, other drawings can also be obtained from these drawings without creative labor.
[0018] Figure 1 A structural diagram of a battery provided in the background art is provided.
[0019] Figure 2 A structural diagram of an explosion-proof valve provided in an embodiment of the present application is provided.
[0020] Figures 3-5 A structural diagram of an explosion-proof valve provided in an embodiment of the present application is provided.
[0021] Figure 6 A structural diagram of a top cover of a battery provided in an embodiment of the present application is provided.
[0022] Figure 7 A structural diagram of a battery provided in an embodiment of the present application is provided.
[0023] Figure 8 A first structural diagram of an electric core and an explosion-proof valve provided in an embodiment of the present application is provided.
[0024] Figure 9 A second structural diagram of an electric core and an explosion-proof valve provided in an embodiment of the present application is provided.
[0025] Reference signs:
[0026] 10, shell; 1, shell body; 2, top cover; 211, explosion-proof hole; 3, explosion-proof valve; 31, explosion-proof middle part; 32, explosion-proof end part; 4, electric core. DETAILED DESCRIPTION
[0027] In order to make the technical problems, technical solutions and beneficial effects of the present application more clearly understood, the following will further describe the present application in combination with the drawings and embodiments. It should be understood that the specific embodiments described herein are only used to explain the present application and not to limit the present application.
[0028] It should be noted that when an element is referred to as being "fixed to" or "disposed on" another element, it can be directly on the other element or indirectly on the other element. When an element is referred to as being "connected to" another element, it can be directly connected to the other element or indirectly connected to the other element.
[0029] It should be understood that the terms "upper", "lower", "top", "bottom", "inner", "outer" and the like indicate relative positions or orientations based on the positions or orientations shown in the drawings, and are used only for the purpose of facilitating the description of the present application and simplifying the description, and do not indicate or imply that the devices or elements referred to must have a particular orientation, be constructed and operated in a particular orientation, and therefore cannot be understood as limiting the present application.
[0030] In addition, the terms "first", "second" are only for descriptive purposes, and cannot be understood as indicating or implying relative importance or implicitly indicating the number of technical features indicated. Therefore, the features defined as "first", "second" can explicitly or implicitly include one or more of the features. In the description of the present application, the meaning of "multiple" is two or more, unless otherwise specifically limited.
[0031] In order to make the purpose, technical scheme and advantages of the present application more clear, the present application will be further described in detail below with reference to the drawings and examples.
[0032] In the prior art, the increase in the size of the explosion-proof valve 3 makes the explosion-proof middle part 31 of the explosion-proof valve 3 relatively weak, so that the explosion-proof middle part 31 of the explosion-proof valve 3 is broken when the internal pressure of the battery does not reach the preset valve opening pressure, which causes the explosion-proof valve 3 to open prematurely, which greatly affects the explosion accuracy of the explosion-proof valve 3.
[0033] To solve this problem, the present application provides an explosion-proof valve 3, which comprises an explosion-proof middle part 31 and an explosion-proof end part 32, and the thickness of the explosion-proof middle part 31 is greater than the thickness of the explosion-proof end part 32.
[0034] Referring to Figures 1-5 With the plane perpendicular to the thickness direction of the explosion-proof valve as the horizontal plane, the explosion-proof middle part 31 and the explosion-proof end part 32 of the present application can be the middle region and the edge region of the explosion-proof valve 3 in a certain specific direction relative to the horizontal plane ( Figures 3-5 ), or the middle region and the edge region of the explosion-proof valve 3 in all directions relative to the horizontal plane ( Figure 2 ). The shape of the explosion-proof valve 3 is not limited, which can be circular, oval, polygonal on the horizontal plane, as long as the explosion-proof valve 3 can fit and completely seal the explosion-proof hole 211, and the explosion-proof valve 3 can break and open when the internal pressure of the battery reaches the preset valve opening pressure.
[0035] The middle region of the explosion-proof valve 3 is far away from the edge of the explosion-proof valve, and the deformation of the middle region is larger than that of the edge region, and the middle region is relatively weak compared with the edge region. By setting the thickness of the explosion-proof middle part 31 to be greater than the thickness of the explosion-proof end part 32, the strength of the explosion-proof middle part 31 is strengthened relative to the explosion-proof end part 32, the explosion-proof valve 3 is prevented from opening prematurely before reaching the preset opening pressure, the explosion accuracy of the explosion-proof valve 3 is improved, and the stability of the battery during long-term use is improved, thereby prolonging the service life of the battery.
[0036] According to some embodiments of the present application, referring to Figure 2 In the horizontal plane, the explosion-proof valve 3 is circular, the explosion-proof middle part 31 is the radial middle part of the explosion-proof valve 3, and the explosion-proof end part 32 is the radial edge of the explosion-proof valve 3, that is, in the horizontal plane perpendicular to the thickness direction of the explosion-proof valve 3, the explosion-proof middle part 31 and the explosion-proof end part 32 are the middle region and the edge region of the explosion-proof valve 3 in each direction relative to the horizontal plane. If the thickness of each part of the circular explosion-proof valve 3 is set to be the same, since the area of the explosion-proof valve 3 is large, the middle region of the explosion-proof valve 3 is relatively weak compared with the edge region, that is, compared with the explosion-proof end part 32, the explosion-proof middle part 31 is relatively weak and is prone to cause the explosion-proof valve 3 to open prematurely. Therefore, by setting the thickness of the explosion-proof middle part 31 to be greater than the thickness of the explosion-proof end part 32, that is, the thickness of the radial middle part of the explosion-proof valve 3 is greater than the thickness of the radial edge, the strength of the explosion-proof middle part 31 is strengthened relative to the explosion-proof end part 32, the premature opening of the explosion-proof valve 3 is effectively prevented, the explosion accuracy of the explosion-proof valve 3 is ensured, and the stability of the battery during long-term use is improved, thereby prolonging the service life of the battery.
[0037] According to some embodiments of the present application, referring to Figure 3In the horizontal plane, the explosion-proof valve 3 is approximately oval-shaped, the explosion-proof middle part 31 is the middle region of the explosion-proof valve 3 in the length direction of the explosion-proof valve 3, and the explosion-proof end part 32 is the edge region of the explosion-proof valve 3 in the length direction of the explosion-proof valve 3, that is, in the horizontal plane perpendicular to the thickness direction of the explosion-proof valve 3, the explosion-proof middle part 31 and the explosion-proof end part 32 are the middle region and the edge region of the explosion-proof valve 3 in a specific direction on the horizontal plane. If the thickness of each part of the explosion-proof valve 3 is set to be the same, since the length of the explosion-proof valve 3 is relatively long, the middle region of the explosion-proof valve 3 in the length direction is relatively weak compared to the edge region, that is, compared to the explosion-proof end part 32, the explosion-proof middle part 31 is relatively weak, which can easily cause the explosion-proof valve 3 to open prematurely; and since the width is relatively small, the difference in deformation can be ignored, so the explosion-proof middle part 31 and the explosion-proof end part 32 can be set only in the length direction of the explosion-proof valve 3, and the thickness of the explosion-proof middle part 31 is set to be greater than the thickness of the explosion-proof end part 32, that is, the thickness of the middle region in the length direction of the explosion-proof valve 3 is greater than the thickness of the edge region, so that the strength of the explosion-proof middle part 31 is strengthened relative to the explosion-proof end part 32, effectively preventing the explosion-proof valve 3 from opening prematurely, ensuring the blasting accuracy of the explosion-proof valve 3, and thereby improving the stability of the battery during long-term use and prolonging the service life of the battery.
[0038] The deformation of different positions in the explosion-proof middle part 31 and the explosion-proof end part 32 is also different, the farther away from the edge of the explosion-proof valve 3, the greater the deformation, that is, the farther away from the edge in the explosion-proof middle part 31 and the explosion-proof end part 32, the weaker the region. According to some embodiments of the present application, the thickness of the explosion-proof middle part 31 decreases in a gradient along the direction from the explosion-proof middle part 31 to the explosion-proof end part 32; and / or, the thickness of the explosion-proof end part 32 increases in a gradient along the direction from the explosion-proof end part 32 to the explosion-proof middle part 31.
[0039] In the explosion-proof middle part 31, the thickness of the explosion-proof middle part 31 decreases in a gradient along the direction from the explosion-proof middle part 31 to the explosion-proof end part 32, that is, the thickness of the explosion-proof middle part 31 increases in a gradient along the direction from the explosion-proof end part 32 to the explosion-proof middle part 31, that is, along the direction away from the edge of the explosion-proof valve 3, the thickness of the explosion-proof middle part 31 gradually increases, so that the strength of each part of the explosion-proof middle part 31 matches the position, effectively preventing the explosion-proof valve 3 from opening prematurely, ensuring the blasting accuracy of the explosion-proof valve 3, and thereby improving the stability of the battery during long-term use and prolonging the service life of the battery.
[0040] In the explosion-proof end part 32, the thickness of the explosion-proof end part 32 increases in a gradient along the direction from the explosion-proof end part 32 to the explosion-proof middle part 31, that is, along the direction away from the edge of the explosion-proof valve 3, the thickness of the explosion-proof end part 32 gradually increases, so that the strength of each part of the explosion-proof end part 32 matches the position, effectively preventing the explosion-proof valve 3 from opening prematurely, ensuring the blasting accuracy of the explosion-proof valve 3, and thereby improving the stability of the battery during long-term use and prolonging the service life of the battery.
[0041] According to some embodiments of the present application, when the size of the explosion valve 3 in each direction of the horizontal plane has a large difference, referring to Figure 3 , the length a of the explosion valve 3 is much greater than the width b of the explosion valve 3, in the length direction of the explosion valve 3, the thickness of the explosion middle part 31 can decrease in the direction from the explosion middle part 31 to the explosion end part 32, and the thickness of the explosion end part 32 can increase in the direction from the explosion end part 32 to the explosion middle part 31; in the width direction of the explosion valve 3, due to the small difference in deformation, the thickness of the explosion middle part 31 and the explosion end part 32 can be uniformly set, that is, the thickness of the explosion middle part 31 in the width direction away from the edge of the explosion valve 3 is equal everywhere, and the thickness of the explosion end part 32 in the width direction away from the edge of the explosion valve 3 is equal everywhere.
[0042] The deformation of the explosion valve 3 at different positions is different, the farther away from the edge of the explosion valve 3, the greater the deformation, that is, the farther away from the edge of the explosion valve 3, the weaker the area in the explosion valve 3. According to some embodiments of the present application, the thickness of the explosion valve 3 decreases in the direction from the explosion middle part 31 to the explosion end part 32. For the whole explosion valve 3, the farther away from the edge of the explosion valve 3, the weaker the explosion valve 3, so by setting the thickness of the explosion valve 3 gradually increasing from the edge to the middle, the strength of the explosion valve 3 everywhere matches the position, effectively preventing the explosion valve 3 from opening prematurely, ensuring the explosion accuracy of the explosion valve 3, and further improving the stability of the battery for long-term use, prolonging the service life of the battery.
[0043] It should be noted that the thickness change of the explosion valve 3 in the present application can come from one side of the thickness direction of the explosion valve 3 ( Figure 8 and Figure 9 ), that is, one side surface of the thickness direction of the explosion valve 3 is a plane, and the other side surface is a non-plane, or from both sides of the thickness direction of the explosion valve 3 ( Figures 3-5 ), that is, both side surfaces of the thickness direction of the explosion valve 3 are non-planes. The plane refers to a straight line formed by connecting any two points on the surface, which is perpendicular to the thickness direction of the explosion valve 3, and the non-plane refers to a straight line formed by connecting two points on the surface, which is not perpendicular to the thickness direction of the explosion valve 3. The non-plane can be convex, concave, stepped or arc surface. In order to prevent the influence of stress concentration on strength, the non-plane is preferably an arc surface.
[0044] According to some embodiments of the present application, the thickness of the thinnest region of the explosion-proof end portion 32 is 0.6-0.95 times the thickness of the thickest region of the explosion-proof middle portion 31. Exemplarily, the thickness of the thinnest region of the explosion-proof end portion 32 can be any value in the range of 0.6 times, 0.65 times, 0.7 times, 0.75 times, 0.8 times, 0.85 times, 0.9 times, and 0.95 times the thickness of the thickest region of the explosion-proof middle portion 31, or any value within the range formed by any two of the above values. When the thickness of the thinnest region of the explosion-proof end portion 32 is too small relative to the thickness of the thickest region of the explosion-proof middle portion 31, i.e., the thickness of the thickest region of the explosion-proof middle portion 31 is too large, the overall strength of the explosion-proof valve 3 is too high, which can cause the explosion-proof valve 3 to fail to normally open when the internal pressure of the battery reaches the opening pressure. When the thickness of the thinnest region of the explosion-proof end portion 32 is too large relative to the thickness of the thickest region of the explosion-proof middle portion 31, i.e., the thickness of the thickest region of the explosion-proof middle portion 31 is too small, the strength of the explosion-proof middle portion 31 is enhanced, but still cannot resist the internal pressure of the battery, so that the explosion-proof valve 3 still opens prematurely. By setting the thickness of the thickest region of the explosion-proof middle portion 31 and the thinnest region of the explosion-proof end portion 32, the thickness of the explosion-proof middle portion 31 and the explosion-proof end portion 32 can be further matched, which effectively prevents the explosion-proof valve 3 from opening prematurely, ensures the explosion accuracy of the explosion-proof valve 3, and thus improves the stability of the battery during long-term use and prolongs the service life of the battery.
[0045] According to some embodiments of the present application, in the first direction, the explosion-proof middle portion 31 accounts for 60%-90% of the length of the explosion-proof valve 3; and / or, in the first direction, the explosion-proof end portion 32 accounts for 5%-20% of the length of the explosion-proof valve 3. The first direction is the direction in which the explosion-proof middle portion 31 and the explosion-proof end portion 32 are arranged on the explosion-proof valve 3 in the horizontal plane, as shown in FIG. 1, which can be any radial direction of the explosion-proof valve 3, as shown in FIG. 2, or the length direction of the explosion-proof valve 3, as shown in FIG. 3. Figure 2 Figure 3
[0046] In the first direction, the explosion-proof middle portion 31 accounts for 60%-90% of the length of the explosion-proof valve 3, exemplarily, in the first direction, the explosion-proof middle portion 31 accounts for any value in the range of 60%, 65%, 70%, 75%, 80%, 85%, and 90% of the length of the explosion-proof valve 3, or any value within the range formed by any two of the above values. For example, in the length direction, the middle region of the explosion-proof valve 3 accounts for 60%-90% of the overall length of the explosion-proof valve 3. When the proportion of the explosion-proof middle portion 31 is too small, the region near the explosion-proof middle portion 31 in the explosion-proof end portion 32 is insufficient in strength, which can easily cause the explosion-proof valve 3 to open prematurely at this position. When the proportion of the explosion-proof middle portion 31 is too large, the overall strength of the explosion-proof valve 3 is too high, which can cause the explosion-proof valve 3 to fail to normally open when the internal pressure of the battery reaches the opening pressure. Figure 3
[0047] In the first direction, the explosion-proof end portion 32 accounts for 5%-20% of the length of the explosion-proof valve 3. Exemplarily, in the first direction, the explosion-proof end portion 32 accounts for any value in 5%, 10%, 15% and 20% of the length of the explosion-proof valve 3 or any value in the range formed by any two of the above values. When the proportion of the explosion-proof end portion 32 is too small, the overall strength of the explosion-proof valve 3 is too high, which may cause the explosion-proof valve 3 to fail to normally open when the internal pressure of the battery reaches the opening pressure. When the proportion of the explosion-proof end portion 32 is too large, the strength of the area of the explosion-proof end portion 32 close to the explosion-proof middle portion 31 is insufficient, which is easy to cause the explosion-proof valve 3 to open at this position in advance.
[0048] According to some embodiments of the present application, the explosion-proof valve 3 comprises a main body portion and a glue layer provided on the surface of the main body portion, and the main body portion is provided with an equal thickness. The explosion-proof valve 3 comprises a main body portion and a glue layer provided on the surface of the main body portion, and the main body portion is provided with an equal thickness, which indicates that the thickness change of different areas of the explosion-proof valve 3 is realized by the change of the thickness of the glue layer.
[0049] It should be noted that the forming mode of the glue layer in the present application is not limited, which can be pasted on the main body portion or coated on the main body portion. The type of the glue layer is not limited, which can be epoxy resin glue, acrylic glue, cyanoacrylate glue, etc. The present application preferably adopts epoxy resin glue because the epoxy resin glue has good high-temperature resistance and is not easy to be affected by the thermal effect inside the battery. The glue layer can be provided on one side surface of the main body portion or on both side surfaces of the main body portion. As shown in the drawings, when the glue layer is provided on the outer side surface of the explosion-proof valve 3 away from the battery cell, it can block the damage of impurities from the outside to the explosion-proof valve 3, and when the glue layer is provided on the inner side surface of the explosion-proof valve 3 close to the battery cell, it can block the corrosion of the battery internal electrolyte to the explosion-proof valve 3. Therefore, the glue layer is preferably provided on both side surfaces of the main body portion. Figure 6
[0050] According to some embodiments of the present application, the explosion-proof valve 3 is integrally formed, and the thickness change of the explosion-proof middle portion 31 and the explosion-proof end portion 32 is formed by the thickness change of the explosion-proof valve 3 itself, without the need to change the thickness by means of external glue layer or other substances, avoiding the influence of voids and other interference factors on the strength, improving the matching accuracy of the strength and position, and better guaranteeing the explosion accuracy of the explosion-proof valve 3.
[0051] The present application also provides a battery, as shown in the drawings, comprising a shell 10 and a battery cell, the shell 10 constitutes a containing cavity, the battery cell is arranged in the containing cavity, and the shell 10 comprises the above explosion-proof valve 3. Figure 7
[0052] According to some embodiments of the present application, the distance from the side of the explosion-proof valve 3 close to the battery cell to the battery cell gradually increases along the explosion-proof middle part 31 towards the explosion-proof end part 32; and / or, the distance from the side of the explosion-proof valve 3 away from the battery cell to the battery cell gradually decreases along the explosion-proof middle part 31 towards the explosion-proof end part 32.
[0053] The change in the thickness of the explosion-proof valve 3 can come from one side of the thickness direction of the explosion-proof valve 3, or from both sides of the thickness direction of the explosion-proof valve 3. In some embodiments, as shown in FIG. 4, the change in the thickness of the explosion-proof valve 3 comes from the side of the explosion-proof valve 3 close to the battery cell 4 (the inner side of the shell 10), and at this time, the surface of the side of the explosion-proof valve 3 close to the battery cell 4 is a non-planar surface, and the surface of the side of the explosion-proof valve 3 away from the battery cell 4 (the outer side of the shell 10) is a planar surface. Figure 8 The distance from the surface of the side of the explosion-proof valve 3 close to the battery cell 4 to the battery cell 4 is set to gradually increase along the explosion-proof middle part 31 towards the explosion-proof end part 32, that is, the surface of the side of the explosion-proof valve 3 close to the battery cell 4 is gradually set away from the battery cell 4 from the explosion-proof middle part 31 to the explosion-proof end part 32, so that in the direction from the explosion-proof middle part 31 to the explosion-proof end part 32, the thickness of the explosion-proof valve 30 gradually decreases, so that the strength and position of each part of the explosion-proof valve 3 are matched, effectively preventing the explosion-proof valve 3 from opening prematurely, ensuring the explosion accuracy of the explosion-proof valve 3, and thereby improving the stability of the battery for long-term use and prolonging the service life of the battery.
[0054] As shown in FIG. 5, in some embodiments, the change in the thickness of the explosion-proof valve 3 comes from the side of the explosion-proof valve 3 away from the battery cell 4 (the outer side of the shell 10), and at this time, the surface of the side of the explosion-proof valve 3 close to the battery cell 4 (the inner side of the shell 10) is a planar surface, and the surface of the side of the explosion-proof valve 3 away from the battery cell 4 is a non-planar surface. Figure 9 The distance from the surface of the side of the explosion-proof valve 3 away from the battery cell 4 to the battery cell 4 is set to gradually decrease along the explosion-proof middle part 31 towards the explosion-proof end part 32, that is, the surface of the side of the explosion-proof valve 3 away from the battery cell 4 is gradually set close to the battery cell 4 from the explosion-proof middle part 31 to the explosion-proof end part 32, so that in the direction from the explosion-proof middle part 31 to the explosion-proof end part 32, the thickness of the explosion-proof valve 30 gradually decreases, so that the strength and position of each part of the explosion-proof valve 3 are matched, effectively preventing the explosion-proof valve 3 from opening prematurely, ensuring the explosion accuracy of the explosion-proof valve 3, and thereby improving the stability of the battery for long-term use and prolonging the service life of the battery.
[0055] In some embodiments, the thickness variation of the explosion-proof valve 3 comes from both sides of the thickness direction of the explosion-proof valve 3, that is, the side surface of the explosion-proof valve 3 towards the battery (the inner side of the shell 10) and the side surface of the explosion-proof valve 3 away from the battery (the outer side of the shell 10) are both non-planar. By gradually arranging the side surface of the explosion-proof valve 3 towards the battery from the explosion-proof middle part 31 to the explosion-proof end part 32 away from the battery and gradually arranging the side surface of the explosion-proof valve 3 away from the battery from the explosion-proof middle part 31 to the explosion-proof end part 32 close to the battery, the thickness of the explosion-proof valve 30 gradually decreases in the direction from the explosion-proof middle part 31 to the explosion-proof end part 32, so that the strength of the explosion-proof valve 3 at different positions is matched, the explosion-proof valve 3 is effectively prevented from opening too early, the explosion accuracy of the explosion-proof valve 3 is ensured, and the stability of the battery during long-term use is improved, and the service life of the battery is prolonged.
[0056] According to some embodiments of the present application, the shell 10 includes a shell body 1 and a top cover 2, and the explosion-proof valve 3 can be arranged on the shell body 1 or the top cover 2. In order to ensure the normal opening of the explosion-proof valve 3 and avoid corrosion of the electrolyte, the explosion-proof valve is preferably arranged on the top cover 2, as shown in Figure 7 .
[0057] When the length and width of the explosion-proof valve 3 are large, the explosion-proof valve 3 will occupy too much space of the top cover 2, and the cost will be too high. When the length and width of the explosion-proof valve 3 are small, the pressure relief value of the explosion-proof valve 3 is small, and the explosion-proof valve 3 is prone to open. In some embodiments, in order to improve the space utilization rate in the battery, the width of the top cover 2 is not too large, as shown in Figure 6 , in order to ensure the strength of the top cover 2 and the explosion-proof valve 3, the length a of the explosion-proof valve 3 accounts for 0.1-0.3 times of the length A of the top cover 2 in the length direction of the top cover 2; and / or, the width b of the explosion-proof valve 3 accounts for 0.4-0.8 times of the width B of the top cover 2 in the width direction of the top cover 2.
[0058] The above is only a preferred embodiment of the present application, and only the technical principle of the present application is specifically described, and these descriptions are only for explaining the principle of the present application, and cannot be explained as a limitation on the protection scope of the present application in any way. Based on the explanation herein, any modification, equivalent replacement and improvement made within the spirit and principle of the present application, and other specific embodiments of the present application which can be thought by those skilled in the art without creative labor, should be included in the protection scope of the present application.
Claims
1. An explosion relief valve, characterized in that The explosion-proof valve comprises an explosion-proof middle part and an explosion-proof end part, the thickness of the explosion-proof middle part is greater than the thickness of the explosion-proof end part; The thickness of the explosion-proof middle part decreases in a gradient along the direction from the explosion-proof middle part to the explosion-proof end part; and / or, the thickness of the explosion-proof end part increases in a gradient along the direction from the explosion-proof end part to the explosion-proof middle part.
2. The explosion relief valve of claim 1, wherein The thickness of the explosion-proof valve decreases in a gradient along the direction from the explosion-proof middle part to the explosion-proof end part.
3. The explosion relief valve of claim 1, wherein, The thickness of the thinnest area of the explosion-proof end part is 0.6-0.95 times the thickness of the thickest area of the explosion-proof middle part.
4. The explosion relief valve of claim 1, wherein, In the first direction, the explosion-proof middle part accounts for 60%-90% of the length of the explosion-proof valve; and / or, in the first direction, the explosion-proof end part accounts for 5%-20% of the length of the explosion-proof valve.
5. Explosion relief valve according to any of claims 1-4, characterized in that The explosion-proof valve comprises a main body part and a glue layer arranged on the surface of the main body part, and the main body part is arranged with equal thickness.
6. Explosion relief valve according to any of claims 1-4, characterized in that The explosion-proof valve is integrally formed.
7. A battery, characterized by The battery comprises a shell and an electric core, the shell constitutes a receiving cavity, the electric core is arranged in the receiving cavity, and the shell comprises the explosion-proof valve according to any one of claims 1-6.
8. The battery of claim 7, wherein the battery is a lithium ion battery. The distance from the side surface of the explosion-proof valve close to the electric core to the electric core gradually increases along the direction from the explosion-proof middle part to the explosion-proof end part; and / or, the distance from the side surface of the explosion-proof valve away from the electric core to the electric core gradually decreases along the direction from the explosion-proof middle part to the explosion-proof end part.
9. The battery of claim 7, wherein, The shell comprises a shell body and a top cover, the explosion-proof valve is arranged on the top cover; in the length direction of the top cover, the length a of the explosion-proof valve accounts for 0.1-0.3 of the length A of the top cover; and / or, in the width direction of the top cover, the width b of the explosion-proof valve accounts for 0.4-0.8 of the width B of the top cover.