Explosion-proof valve and battery pack

Abstract

The utility model discloses an explosion-proof valve and a battery pack, the explosion-proof valve comprises a main body, the main body comprises a thinning area, the thinning area is provided with a reinforcing protrusion protruding along a first direction, and the first direction is the thickness direction of the thinning area. According to the explosion-proof valve, the overall structural strength of the thinning area is improved by constructing the reinforcing protrusions on the thinning area, the fatigue fracture resistance is high, and the leakage-proof effect is good.

Description

Technical Field

[0001] The utility model relates to the technical field of batteries, and specifically, to an explosion-proof valve and a battery pack. Background Art

[0002] To increase the cruising range of new energy vehicles, the size of single batteries shows a design trend of gradually increasing. To ensure the safety of the battery cells during thermal runaway, the design size of the corresponding explosion-proof valve also becomes larger and larger. In the design of large-size explosion-proof valves, in order to ensure the durability of the explosion-proof valve during use, a strengthening structure is generally designed in the valve body area in the middle of the explosion-proof valve. The conventional design scheme is to form reinforcing ribs on the explosion-proof valve body by means of local stamping. The reinforcing ribs divide the explosion-proof valve into multiple areas, thereby realizing the strengthening of the explosion-proof valve. However, in the working condition of repeated expansion of the battery inner cavity, the problem of fatigue cracking at the position of the reinforcing ribs will occur, resulting in liquid leakage of the explosion-proof valve. Summary of the Utility Model

[0003] The utility model aims to solve at least one of the technical problems in the related technologies to a certain extent.

[0004] In the technical solution of the utility model, an explosion-proof valve is provided. The thinning area of the explosion-proof valve is provided with a reinforcing protrusion protruding along its thickness direction. Compared with the reinforcing ribs formed by stamping, the anti-fatigue fracture ability is strong and the anti-leakage effect is good.

[0005] The explosion-proof valve of the embodiment of the utility model includes a main body. The main body includes a thinning area. The thinning area is provided with a reinforcing protrusion protruding along a first direction, and the first direction is the thickness direction of the thinning area.

[0006] For the explosion-proof valve of the embodiment of the utility model, the thinning area is provided with a reinforcing protrusion protruding along its thickness direction. Thus, the reinforcing protrusion can improve the structural strength of the thinning area. And compared with the reinforcing ribs formed by traditional stamping, in this application, some areas of the thinning area are directly protruded to form the reinforcing protrusion or the reinforcing protrusion is arranged on the thinning area, and there is no problem of easy fatigue fracture at the stamping position of the reinforcing ribs formed by stamping. The anti-fatigue fracture ability is strong and the anti-leakage effect is good.

[0007] In some embodiments, the central axis of the reinforcing protrusion is collinear with the central axis of the thinning area.

[0008] In some embodiments, the reinforcing protrusion includes a main protrusion and at least one side protrusion. The side protrusion is connected to the main protrusion, and in a first projection plane, the orthographic projection of the side protrusion is located on one side of the orthographic projection of the main protrusion, and the first projection plane is perpendicular to the first direction.

[0009] In some embodiments, in the first projection plane, the area of the orthographic projection of the side protrusion is smaller than the area of the orthographic projection of the main protrusion.

[0010] In some embodiments, there are a plurality of the side protrusions, and the plurality of the side protrusions include at least one first side protrusion and at least one second side protrusion. And in the first projection plane, the front projection of the first side protrusion and the front projection of the second side protrusion are located on different sides of the front projection of the main protrusion.

[0011] In some embodiments, in the first projection plane, the dimension A1 of the front projection of the main protrusion in the second direction and the dimension A of the front projection of the thinning area in the second direction satisfy 0.75 ≤ A1 / A ≤ 0.95;

[0012] The dimension B1 of the front projection of the main protrusion in the third direction and the dimension B of the front projection of the thinning area in the third direction satisfy 0.15 ≤ B1 / B ≤ 0.35, and the third direction is perpendicular to the second direction.

[0013] In some embodiments, in the first projection plane, the front projection of the first side protrusion and the front projection of the second side protrusion are relatively located on both sides of the front projection of the main protrusion in the third direction. The distance B2 between the end of the front projection of the first side protrusion deviating from the front projection of the main protrusion and the end of the front projection of the second side protrusion deviating from the front projection of the main protrusion and the dimension B of the front projection of the thinning area in the third direction satisfy 0.25 ≤ B2 / B ≤ 0.45. The dimensions A2 of the front projections of the first side protrusion and the second side protrusion in the second direction are equal and satisfy 0.08 ≤ A2 / A ≤ 0.4 with the dimension A of the front projection of the thinning area in the second direction.

[0014] In some embodiments, in the first projection plane, the geometric centers of the front projections of the first side protrusion, the geometric center of the front projection of the second side protrusion, and the geometric center of the front projection of the main protrusion are collinear.

[0015] In some embodiments, the heights H of the main protrusion and the side protrusions in the first direction are equal and satisfy 0.2 mm ≤ H ≤ 1 mm.

[0016] The battery pack of the embodiment of the present utility model includes the explosion-proof valve described in the above embodiment.

[0017] For the battery pack of the embodiment of the present utility model, by adopting the above explosion-proof valve, a reinforcing protrusion protruding along the thickness direction is provided in the thinning area. Thus, the reinforcing protrusion can improve the structural strength of the thinning area. And compared with the reinforcing rib formed by traditional stamping, in this application, a part of the area of the thinning area directly protrudes to form a reinforcing protrusion or a reinforcing protrusion is provided on the thinning area, and there is no problem of easy fatigue fracture at the stamping position existing in the reinforcing rib formed by stamping. It has strong anti-fatigue fracture ability and good leak-proof effect. BRIEF DESCRIPTION OF THE DRAWINGS

[0018] Figure 1 FIG. 1 is a schematic structural view of an explosion-proof valve according to an embodiment of the present invention.

[0019] Figure 2 FIG. 2 is a cross-sectional view of a connecting portion of the explosion-proof valve according to an embodiment of the present invention, showing a thinning section therein.

[0020] Figure 3 FIG. 3 is a cross-sectional view of a connecting portion of the explosion-proof valve according to an embodiment of the present invention, showing a connecting section therein.

[0021] Figure 4 FIG. 4 is a top view of the explosion-proof valve according to an embodiment of the present invention.

[0022] Figure 5 FIG. 5 is a schematic structural view of an explosion-proof valve according to another embodiment of the present invention.

[0023] Reference numerals:

[0024] Welding portion 1, connecting portion 2, thinning section 21, connecting section 22, thinning area 3, strengthening protrusion 4, main protrusion 41, side protrusion 42. DETAILED DESCRIPTION OF THE EMBODIMENTS

[0025] Embodiments of the present invention will be described in detail below. Examples of the embodiments are shown in the drawings. The embodiments described below with reference to the drawings are exemplary and are intended to explain the present invention and should not be construed as limiting the present invention.

[0026] As shown in FIG. Figures 1-5 1, the explosion-proof valve of the present invention includes a main body. The main body includes a thinning area 3. The thinning area 3 is provided with a strengthening protrusion 4 protruding along a first direction. The first direction is the thickness direction of the thinning area 3. Specifically, as shown in FIG. Figure 1 1, the main body further includes a welding portion 1 and a connecting portion 2. The welding portion 1 surrounds the outer periphery of the thinning area 3 and is connected to the thinning area 3 through the connecting portion 2. Optionally, the strengthening protrusion 4 may be formed by directly protruding a partial area of the thinning area 3 along its thickness direction, or may be connected to the thinning area 3 as an independent structural member.

[0027] It should be noted that in the traditional explosion-proof valve strengthening, local recessed reinforcing ribs are formed by stamping. The reinforcing ribs can be arranged staggeredly on the thinning area 3. The thickness at the recessed position is less than the thickness of the thinning area 3 of the explosion-proof valve. Repeated expansion inside the battery easily causes fatigue fracture at the position of the reinforcing ribs. In this application, part of the area of the thinning area 3 is directly made to protrude to form a strengthening structure or a strengthening protrusion 4 is arranged on the thinning area 3, eliminating the problem of easy fatigue fracture at the stamping position of the reinforcing ribs formed by stamping. Thus, while strengthening the structure of the thinning area 3, it has good anti-fatigue fracture ability.

[0028] In the explosion-proof valve of the embodiment of the present utility model, the thinning area 3 is provided with a strengthening protrusion 4 protruding along its thickness direction. Thus, the strengthening protrusion 4 can improve the structural strength of the thinning area 3. And compared with the reinforcing ribs formed by traditional stamping, in this application, part of the area of the thinning area 3 is directly made to protrude to form a strengthening protrusion 4 or a strengthening protrusion 4 is arranged on the thinning area 3, eliminating the problem of easy fatigue fracture at the stamping position of the reinforcing ribs formed by stamping, having strong anti-fatigue fracture ability and good leak-proof effect.

[0029] Optionally, the strengthening protrusion 4 can be a rounded rectangular structure or a Figure 5 track-shaped structure as shown, and is not limited herein.

[0030] Furthermore, the central axis of the strengthening protrusion 4 is collinear with the central axis of the thinning area 3. In other words, the strengthening protrusion 4 is located in the middle of the thinning area 3, and the strengthening effect on each position of the thinning area 3 is more uniform.

[0031] Furthermore, as Figure 1 shown, the strengthening protrusion 4 includes a main protrusion 41 and at least one side protrusion 42. The side protrusion 42 is connected to the main protrusion 41, and in the first projection plane, the orthographic projection of the side protrusion 42 is located on one side of the orthographic projection of the main protrusion 41. The first projection plane is perpendicular to the first direction.

[0032] Thus, the main protrusion 41 can strengthen the central area of the thinning area 3, and the side protrusion 42 extends relative to the main protrusion 41 towards the edge area to strengthen the edge area.

[0033] Further, on the first projection plane, the area of the orthographic projection of the side protrusion 42 is smaller than the area of the orthographic projection of the main protrusion 41. It should be noted that the area of the single reinforcing protrusion 4 needs to be limited within a certain range. For example, when the reinforcing protrusion 4 is too small, its strengthening effect on the remaining area of the thinning area 3 will be reduced, while when the reinforcing protrusion 4 is too large, the coverage range of the reinforcing protrusion 4 itself is too large, and the structural strength of its middle area will be reduced. Therefore, by setting the side protrusion 42 as a smaller protrusion structure, the area of the entire reinforcing protrusion 4 can be within a suitable range to avoid a decrease in the structural strength of the reinforcing protrusion 4 itself. At the same time, the extension of the side protrusion 42 towards the edge area of the thinning area 3 can be used to strengthen the edge area of the thinning area 3, that is, both the strengthening effect of the reinforcing protrusion 4 on the thinning area 3 and the requirements for its own structural strength are taken into account.

[0034] Preferably, as Figure 1 shown, there are multiple side protrusions 42. The multiple side protrusions 42 include at least one first side protrusion and at least one second side protrusion, and on the first projection plane, the orthographic projections of the first side protrusion and the second side protrusion are located on different sides of the orthographic projection of the main protrusion 41. In other words, the multiple side protrusions 42 can strengthen the thinning area 3 from different orientations, making the strengthening effect of the reinforcing protrusion 4 on each area of the thinning area 3 more uniform.

[0035] Further, the connecting portion 2 includes a scoring segment and a connecting segment 22 that are connected along the circumference of the thinning area 3. The scoring segment is provided with a thinning segment 21 that extends along the circumference of the thinning area 3, and the thickness dimension of the thinning segment 21 is smaller than the thickness dimension of the connecting segment 22. Thus, the structural strength of the thinning segment 21 is less than that of the connecting segment 22. When the internal battery goes out of control and impacts the explosion-proof valve, the thinner thinning segment 21 can break to achieve the explosion-proof function, and the thicker connecting segment 22 can prevent the thinning area 3 from detaching from the welding portion 1, and there will be no problem of system short circuit caused by the flying out of the thinning area 3 of the explosion-proof valve.

[0036] Optionally, as Figure 1 shown, the connecting portion 2 is in a runway shape. One long straight side of the runway shape is the connecting segment 22, and the remaining area is the scoring segment. When there is a thermal runaway inside the battery pack, the thinning area 3 can be lifted from one side under the restriction of the connecting portion 2 but will not detach from the welding portion 1.

[0037] Further, as Figure 4 shown, on the first projection plane, the dimension A1 of the orthographic projection of the main protrusion 41 in the second direction and the dimension A of the orthographic projection of the thinning area 3 in the second direction satisfy 0.75 ≤ A1 / A ≤ 0.95. For example, A1 / A is 0.75, 0.8, 0.85, 0.9, or 0.95;

[0038] The dimension B1 of the orthographic projection of the main protrusion 41 in the third direction and the dimension B of the orthographic projection of the thinning area 3 in the third direction satisfy 0.15 ≤ B1 / B ≤ 0.35. For example, B1 / B is 0.15, 0.2, 0.25, 0.3, or 0.35, and the third direction is perpendicular to the second direction. For example, as Figure 4 shown, the second direction is the width direction of the thinning area 3, and the third direction is the length direction of the thinning area 3.

[0039] It should be noted that the larger the orthographic projection area of a single protrusion on the first projection plane, the stronger the strengthening effect on the remaining area of the thinning area 3, but at the same time, the structural strength of the protrusion itself will be smaller. The inventors of this application have found through research that when the layout ratio of the main protrusion 41 in the width direction of the thinning area 3 is between 0.75 and 0.95, and the layout ratio in the length direction of the thinning area 3 is between 0.15 and 0.35, the strengthening effect on the thinning area 3 and its own structural strength can be taken into account.

[0040] It can be understood that according to the area size of the thinning area 3, the main protrusion 41 can be arranged in a suitable proportion. For example, when the area of the thinning area 3 is large, A1 / A can be 0.95, and B1 / B can be 0.35. That is to say, the main protrusion 41 has a large layout ratio in both the length direction and the width direction of the thinning area 3 to meet the strengthening requirements of the thinning area 3 with a large area.

[0041] When the area of the thinning area 3 is small, A1 / A can be 0.75, and B1 / B can be 0.15, which can meet the strengthening requirements of the thinning area 3 with a small area.

[0042] Furthermore, as Figure 4 shown, on the first projection plane, the orthographic projections of the first side protrusion and the second side protrusion are relatively located on both sides of the orthographic projection of the main protrusion 41 in the third direction. The distance B2 between the end of the orthographic projection of the first side protrusion facing away from the orthographic projection of the main protrusion 41 and the end of the orthographic projection of the second side protrusion facing away from the orthographic projection of the main protrusion 41 and the dimension B of the orthographic projection of the thinning area 3 in the third direction satisfy 0.25 ≤ B2 / B ≤ 0.45. For example, B2 / B is 0.25, 0.3, 0.35, 0.4, or 0.45. The dimensions A2 of the orthographic projections of the first side protrusion and the second side protrusion in the second direction are equal and satisfy 0.08 ≤ A2 / A ≤ 0.4. For example, A2 / A is 0.08, 0.1, 0.2, 0.3, or 0.4.

[0043] In other words, on both sides of the main protrusion 41 in the length direction of the thinning area 3, a side protrusion 42 is respectively provided to increase the strengthening range in the length direction of the thinning area 3, compensating for the problem of the small strengthening area caused by the small layout ratio of the main protrusion 41 in the length direction of the thinning area 3. Moreover, the inventor of the present application has found through research that when the ratio of the total layout distance of the first side protrusion and the second side protrusion in the length direction of the thinning area 3 is between 0.25 and 0.45, and the layout ratio in the width direction of the thinning area 3 is between 0.08 and 0.4, the strengthening effect on the thinning area 3 and the structural strength of the side protrusion 42 itself can be taken into account.

[0044] It can be understood that according to the area size of the thinning area 3, the side protrusions 42 can be arranged in a suitable proportion. For example, when the area of the thinning area 3 is large, B2 / B can be 0.45 and A2 / A can be 0.4. That is to say, the side protrusions 42 have a large layout ratio in both the length direction and the width direction of the thinning area 3 to meet the strengthening requirements of the thinning area 3 with a large area.

[0045] When the area of the thinning area 3 is small, B2 / B can be 0.25 and A2 / A can be 0.08, which can meet the strengthening requirements of the thinning area 3 with a small area.

[0046] Preferably, on the first projection plane, the geometric centers of the positive projections of the first side protrusion, the geometric center of the positive projection of the second side protrusion, and the geometric center of the positive projection of the main protrusion 41 are collinear. Thus, the entire protrusion structure including the main protrusion 41 and the side protrusions 42 is located in the middle of the thinning area 3, facilitating uniform strengthening of each area of the thinning area 3.

[0047] Furthermore, the heights of the main protrusion 41 and the side protrusions 42 in the first direction are both H, and 0.2 mm ≤ H ≤ 1 mm is satisfied. For example, H can be 0.2 mm, 0.4 mm, 0.6 mm, 0.8 mm, or 1 mm. It should be noted that when the protruding dimensions of the main protrusion 41 and the side protrusions 42 are too small, the strengthening effect will be reduced, while when the protruding dimensions are too large, it will occupy the assembly space of the battery pack and may interfere with the assembly of other components. When the protruding dimensions are between 0.2 mm and 1 mm, the strengthening effect can be taken into account while avoiding affecting the assembly space. Specifically, the protruding height of the strengthening protrusion 4 can be determined according to the area size of the thinning area 3. For example, when the area of the thinning area 3 is small and the strengthening requirement is small, the height of the strengthening protrusion 4 can be 0.2 mm, and when the area of the thinning area 3 is large and the strengthening requirement is large, the height of the strengthening protrusion 4 can be 1 mm.

[0048] The battery pack of the embodiment of the present utility model includes the explosion-proof valve of the above embodiment.

[0049] For the battery pack according to the embodiment of the present utility model, by adopting the above explosion-proof valve, the thinning area 3 is provided with a reinforcing protrusion 4 protruding along its thickness direction. Thus, the reinforcing protrusion 4 can improve the structural strength of the thinning area 3. Moreover, compared with the reinforcing ribs formed by traditional stamping, in this application, a part of the area of the thinning area 3 is directly made to protrude to form the reinforcing protrusion 4 or the reinforcing protrusion 4 is arranged on the thinning area 3, and there is no problem of easy fatigue fracture at the stamping position existing in the reinforcing ribs formed by stamping. It has strong anti-fatigue fracture ability and good leak prevention effect.

[0050] In the description of the present utility model, it should be understood that the orientation or positional relationship indicated by the terms "center", "longitudinal", "transverse", "length", "width", "thickness", "upper", "lower", "front", "rear", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", "clockwise", "counterclockwise", "axial", "radial", "circumferential", etc. is based on the orientation or positional relationship shown in the drawings, and is only for the convenience of describing the present utility model and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and thus should not be construed as a limitation of the present utility model.

[0051] In addition, the terms "first" and "second" are only used for descriptive purposes and cannot be understood as indicating or implying relative importance or implicitly specifying the quantity of the indicated technical features. Thus, the features defined with "first" and "second" may explicitly or implicitly include at least one of such features. In the description of the present utility model, the meaning of "a plurality" is at least two, such as two, three, etc., unless otherwise specifically and clearly defined.

[0052] In the present utility model, unless otherwise clearly specified and limited, the terms "mounted", "connected", "connected to", "fixed" and other terms should be understood in a broad sense. For example, it may be a fixed connection, a detachable connection, or integrated; it may be a mechanical connection, an electrical connection or communication with each other; it may be directly connected, or indirectly connected through an intermediate medium, and may be the internal communication of two elements or the interaction relationship between two elements, unless otherwise clearly limited. For those of ordinary skill in the art, the specific meanings of the above terms in the present utility model can be understood according to specific circumstances.

[0053] In the present utility model, unless otherwise clearly specified and defined, the first feature being "on" or "under" the second feature may mean that the first and second features are in direct contact, or the first and second features are in indirect contact through an intermediate medium. Moreover, the first feature being "above", "over" and "on top of" the second feature may mean that the first feature is directly above or obliquely above the second feature, or merely indicates that the horizontal height of the first feature is higher than that of the second feature. The first feature being "under", "below" and "beneath" the second feature may mean that the first feature is directly below or obliquely below the second feature, or merely indicates that the horizontal height of the first feature is less than that of the second feature.

[0054] In the present utility model, the terms "one embodiment", "some embodiments", "example", "specific example", or "some examples", etc. mean that the specific features, structures, materials, or characteristics described in connection with the embodiment or example are included in at least one embodiment or example of the present utility model. In this specification, the schematic representations of the above terms do not necessarily refer to the same embodiment or example. Moreover, the specific features, structures, materials, or characteristics described can be combined in a suitable manner in any one or more embodiments or examples. In addition, without contradiction, those skilled in the art can combine and combine the different embodiments or examples described in this specification and the features of different embodiments or examples.

[0055] It should be understood that the present utility model does not limit its application to the detailed structure and arrangement of the components set forth in this specification. The present utility model can have other embodiments and can be implemented and executed in various ways. The foregoing variations and modifications fall within the scope of the present utility model. It should be understood that the present utility model as described and defined in this specification extends to all alternative combinations of two or more separate features mentioned or apparent in the text and / or drawings. All such different combinations constitute multiple alternative aspects of the present utility model. The embodiments of this specification illustrate the best mode known for implementing the present utility model and will enable those skilled in the art to utilize the present utility model.

Claims

1. An explosion-proof valve, characterized in that: The invention comprises a main body, wherein the main body comprises a thinning area, and the thinning area is provided with a reinforcing protrusion protruding along a first direction, wherein the first direction is a thickness direction of the thinning area.

2. The explosion-proof valve according to claim 1, characterized in that: The central axis of the reinforcing protrusion is collinear with the central axis of the thinning area.

3. The explosion-proof valve according to claim 1, characterized in that: The reinforcing protrusion includes a main protrusion and at least one side protrusion, the side protrusion is connected to the main protrusion, and on a first projection plane, the orthographic projection of the side protrusion is located on one side of the orthographic projection of the main protrusion, and the first projection plane is perpendicular to the first direction.

4. The explosion-proof valve according to claim 3, characterized in that: On the first projection plane, an area of ​​an orthographic projection of the side protrusion is smaller than an area of ​​an orthographic projection of the main protrusion.

5. The explosion-proof valve according to claim 3, characterized in that: There are multiple side protrusions, including at least one first side protrusion and at least one second side protrusion, and on the first projection plane, the orthographic projection of the first side protrusion and the orthographic projection of the second side protrusion are located on different sides of the orthographic projection of the main protrusion.

6. The explosion-proof valve according to claim 5, characterized in that: On the first projection plane, a dimension A1 of an orthographic projection of the main protrusion in the second direction and a dimension A of an orthographic projection of the thinned area in the second direction satisfy 0.75≤A1 / A≤0.95; A dimension B1 of the orthographic projection of the main protrusion in the third direction and a dimension B of the orthographic projection of the thinned area in the third direction satisfy 0.15≤B1 / B≤0.35, and the third direction is perpendicular to the second direction.

7. The explosion-proof valve according to claim 6, characterized in that: On the first projection plane, the orthographic projection of the first side protrusion and the orthographic projection of the second side protrusion are relatively located on both sides of the orthographic projection of the main protrusion in the third direction, the distance B2 between the end of the orthographic projection of the first side protrusion facing away from the orthographic projection of the main protrusion and the end of the orthographic projection of the second side protrusion facing away from the orthographic projection of the main protrusion and the dimension B of the orthographic projection of the thinning zone in the third direction satisfy 0.25≤B2 / B≤0.45, the orthographic projection of the first side protrusion and the orthographic projection of the second side protrusion in the second direction are equal to the dimension A2 and satisfy 0.08≤A2 / A≤0.4 with the dimension A of the orthographic projection of the thinning zone in the second direction.

8. The explosion-proof valve according to claim 7, characterized in that: On the first projection plane, a geometric center of an orthographic projection of the first side protrusion, a geometric center of an orthographic projection of the second side protrusion, and a geometric center of an orthographic projection of the main protrusion are collinear.

9. The explosion-proof valve according to claim 3, characterized in that: The heights H of the main protrusion and the side protrusion in the first direction are equal and satisfy 0.2 mm≤H≤1 mm.

10. A battery pack, characterized in that: Comprising an explosion-proof valve according to any one of claims 1-9.

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