Explosion-proof valves and batteries

Abstract

The present invention discloses an explosion-proof valve and a battery, the explosion-proof valve comprising a body (100) provided with a score (200) and a buffer groove (300), both of which are racetrack shaped, the score (200) comprising a deep groove (220) and a shallow groove (210), the depth of the shallow groove (210) being D, the distance between the bottom wall of the shallow groove (210) and the bottom wall of the body (100) being T1, the distance between the bottom wall of the deep groove (220) and the bottom wall of the body (100) being T2, and the distance between the bottom wall of the buffer groove (300) and the bottom wall of the body (100) being T3, where D>0, T3>T2, and T1>T2.

Description

Technical Field

[0001] This application claims the priority of a Chinese patent application with an application number of 202420976935.2 and a title of "Explosion-proof Valve and Battery" filed on May 7, 2024, and all of its contents are incorporated herein by reference.

[0002] The present invention relates to the field of battery technology, and particularly to an explosion-proof valve and a battery.

Background Art

[0003] As an important functional component in a battery, an explosion-proof valve can achieve an excellent explosion-proof effect and ensure the safety of electric vehicles powered by power batteries. The set opening pressure of the explosion-proof valve for different battery models or functions is different. It is necessary to set the set opening pressure of the explosion-proof valve of some batteries to be small, but it is restricted by technical influences such as the process. Currently, the manufacturing cost of explosion-proof valves with a small set opening pressure is high.

Summary of the Invention

[0004] An object of the present invention is to solve at least one of the technical problems existing in the prior art. For this reason, the present invention provides an explosion-proof valve that can effectively reduce the manufacturing cost of an explosion-proof valve with a small opening pressure.

[0005] The present invention further provides a battery having the above explosion-proof valve.

[0006] The explosion-proof valve according to an embodiment of the first aspect of the present invention includes a main body provided with a score and a buffer groove, both the score and the buffer groove being in a racetrack shape, the score includes a deep groove part and a shallow groove part, the depth of the shallow groove part is D, the distance between the bottom wall of the shallow groove part and the bottom wall of the main body is T1, and the distance between the bottom wall of the deep groove part and the bottom wall of the main body is T2, the distance between the bottom wall of the buffer groove and the bottom wall of the main body is T3, D>0, T3>T2, and T1>T2.

[0007] The explosion-proof valve according to the embodiment of the present invention has at least the following beneficial effects: By providing a buffer groove, the stress on the score can be significantly reduced under working conditions such as cell production, pack assembly, and vibration of the entire vehicle, preventing fatigue cracks and malfunctions caused by excessive stress on the score; the score can break and open when a pressure exceeding a predetermined pressure value is applied to the body, thereby releasing pressure in a timely manner when the internal pressure rises abnormally due to thermal runaway of the cell, and preventing the cell from exploding; the score is racetrack-shaped and includes deep grooves and shallow grooves, with the depth of the shallow grooves being non-zero, thereby reducing manufacturing costs and effectively reducing the set opening pressure of the explosion-proof valve.

[0008] According to some embodiments of the present invention, the distance T1 between the bottom wall of the shallow groove and the bottom wall of the main body, and the distance T3 between the bottom wall of the buffer groove and the bottom wall of the main body, satisfy T3 > T1.

[0009] According to some embodiments of the present invention, the score is provided on the outer circumference of the buffer groove, or the buffer groove is provided on the outer circumference of the score.

[0010] According to some embodiments of the present invention, the length of the shallow groove is 1 / 10 to 1 / 3 of the total length of the score.

[0011] According to some embodiments of the present invention, the cross-sectional shape of the shallow groove portion is an inverted trapezoid, and / or the cross-sectional shape of the deep groove portion is an inverted trapezoid.

[0012] According to some embodiments of the present invention, the width of the top of the score is 0.2 mm to 0.6 mm.

[0013] According to some embodiments of the present invention, the width of the top of the shallow groove is W1, the width of the top of the deep groove is W2, and W1 = W2.

[0014] According to some embodiments of the present invention, the range of the value of the distance T1 between the bottom wall of the shallow groove and the bottom wall of the main body is T1 = 30 μm to 100 μm.

[0015] According to some embodiments of the present invention, the depth of the buffer groove is greater than the depth of the score, and / or the width of the buffer groove is greater than the width of the score.

[0016] A battery according to a second embodiment of the present invention includes the above-mentioned explosion-proof valve, and since the battery includes the above-mentioned explosion-proof valve, it has at least all of the beneficial effects of the explosion-proof valve. The explosion-proof valve of this embodiment, by providing a buffer groove, can significantly reduce the stress on the score under working conditions such as cell production, pack assembly, and vibration of the entire vehicle, and can prevent fatigue cracks and malfunctions caused by excessive stress on the score. The score can break and open when a pressure exceeding a predetermined pressure value is applied to the body, so it can release pressure in a timely manner when the internal pressure rises abnormally due to thermal runaway of the cell, and can prevent the cell from exploding. The score is racetrack shaped and includes deep grooves and shallow grooves, and the depth of the shallow grooves is not zero, which reduces manufacturing costs and can effectively reduce the set opening pressure of the explosion-proof valve.

[0017] Additional aspects and advantages of the present invention are partially shown in the following description, and the rest will be apparent from the following description or understood through the practice of the present invention. [Brief explanation of the drawing]

[0018] The present invention will be further described below with reference to the drawings and embodiments. [Figure 1] This is a schematic diagram of the structure of an explosion-proof valve according to an embodiment of the first aspect of the present invention. [Figure 2] This is a cross-sectional view of a first embodiment of the explosion-proof valve of the present invention. [Figure 3] This is an enlarged view of section A in Figure 2. [Figure 4] This is an enlarged view of section B in Figure 2. [Figure 5] Cross-sectional view of the second embodiment of the explosion-proof valve of the present invention. [Figure 6] It is an enlarged view of part C in FIG. 5. [Figure 7] It is an enlarged view of part D in FIG. 5.

Mode for Carrying Out the Invention

[0019] Hereinafter, embodiments of the present invention will be described in detail. Examples of the described embodiments are shown in the drawings, and the same or similar symbols throughout indicate the same or similar elements or elements having the same or similar functions. The embodiments described below with reference to the drawings are exemplary only and are merely for explaining the present invention, and should not be construed as limiting the present invention.

[0020] In the description of the present invention, regarding the description of directions, for example, the directions or positional relationships indicated by up, down, etc. are based on the directions or positional relationships shown in the drawings, and are merely for the convenience of description and simplification of the description of the present invention, and do not indicate or imply that the shown device or element must have a specific direction, be configured and operated in a specific direction. Therefore, it should not be construed as limiting the present invention.

[0021] In the description of the present invention, "plurality" refers to two or more. When "first" or "second" is described, it is merely for distinguishing technical features and should not be understood as indicating or implying relative importance, implicitly specifying the number of the shown technical features, or implicitly specifying the order of the shown technical features.

[0022] In the description of the present invention, unless specifically limited explicitly, terms such as installation, attachment, connection, etc. should be understood in a broad sense, and those skilled in the art can reasonably determine the specific meaning of the above terms in the present invention in combination with the specific content of the technical solution.

[0023] Explosion-proof valves are important functional components in batteries. They open when the internal pressure of the battery reaches the valve's set pressure, releasing the pressure and preventing the battery from exploding. However, currently, there is a problem in that the manufacturing cost of explosion-proof valves is high when the set pressure for explosion protection of batteries is low. To solve this technical problem to at least some extent, this embodiment provides an explosion-proof valve that can effectively reduce the manufacturing cost of explosion-proof valves with low set pressures. The explosion-proof valve of this embodiment will be described in detail below with reference to the drawings.

[0024] Referring to Figures 1 to 7, the explosion-proof valve of the embodiment of the present invention includes a body 100, the body 100 is provided with a score 200 and a buffer groove 300. The buffer groove 300 is used to reduce the stress on the score 200 under working conditions such as cell production, pack assembly, and vibration of the entire vehicle, and to prevent fatigue cracks and malfunctions caused by excessive stress on the score 200. The score 200 can break and open when the body 100 is subjected to a pressure exceeding a predetermined pressure value, thereby releasing pressure in a timely manner when the internal pressure rises abnormally due to thermal runaway of the battery, and preventing the battery from exploding. The distance between the bottom wall of score 200 and the bottom wall of body 100 affects the set pressure of the explosion-proof valve. Generally, the greater the distance between the bottom wall of score 200 and the bottom wall of body 100, the higher the opening pressure of the explosion-proof valve. Conversely, the smaller the distance, the lower the opening pressure of the explosion-proof valve. If a low opening pressure is required for the explosion-proof valve, the distance between the bottom wall of score 200 and the bottom wall of body 100 must be reduced. However, as the distance between the bottom wall of score 200 and the bottom wall of body 100 decreases, the manufacturing precision increases, and the cost rises. Furthermore, if the distance between the bottom wall of score 200 and the bottom wall of body 100 is too small, it becomes difficult to install the entire explosion-proof valve, and the position of score 200 becomes prone to damage.

[0025] To solve the above technical problems to at least some extent, the explosion-proof valve according to this embodiment has a score 200 that is a complete racetrack shape, and the score 200 is divided into a deep groove section 220 and a shallow groove section 210 according to the difference in depth, and the depth of the deep groove section 220 is greater than the depth of the shallow groove section 210, that is, the distance between the bottom wall of the deep groove section 220 and the bottom wall of the main body 100 is smaller than the distance between the bottom wall of the shallow groove section 210 and the bottom wall of the main body 100. Currently, the score 200 of most explosion-proof valves is not a complete racetrack shape, but has a connecting portion to connect the outer circumference and the central portion of the main body 100, and the thickness of the connecting portion is approximately the same as the thickness of the main body 100. In other words, currently, the connecting portion of a normal explosion-proof valve corresponds to the shallow groove portion 210 in this embodiment, and the score 200 of a normal explosion-proof valve corresponds to the deep groove portion 220 in this embodiment. By making the score 200 a complete racetrack shape and dividing the score 200 into a deep groove portion 220 and a shallow groove portion 210, the depth of the deep groove portion 220 in this embodiment is the same as the depth of the normal score 200. In some cases, the opening pressure of the explosion-proof valve in this embodiment can be significantly reduced. That is, if the opening pressure of the explosion-proof valve in this embodiment is the same as that of a normal explosion-proof valve, the depth of the deep groove portion 220 of the explosion-proof valve in this embodiment can be shallower than the depth of the score 200 of a normal explosion-proof valve. This reduces the required machining precision and effectively lowers production costs. At the same time, the shallow groove portion 210 can perform the same function as the connection portion of a normal explosion-proof valve. Even if the deep groove portion 220 ruptures, the shallow groove portion 210 can connect the outer circumference and the central portion of the main body 100, thus avoiding damage caused by the central portion of the main body 100 popping out.

[0026] To facilitate understanding of the technical proposal of this embodiment, as shown in Figures 2 to 7, if the depth of the shallow groove 210 is D, the distance between the bottom wall of the shallow groove 210 and the bottom wall of the main body 100 is T1, and the distance between the bottom wall of the deep groove 220 and the bottom wall of the main body 100 is T2, then D > 0 and T1 > T2.

[0027] In an embodiment of the present invention, if T3 is the distance between the bottom wall of the buffer groove 300 and the bottom wall of the main body 100, then T3 > T2. The purpose of this is to ensure that when the pressure inside the cell rises, the explosion-proof valve ruptures at the score 200 rather than at the buffer groove 300, and the buffer groove 300 provides a good buffering effect, allowing the score 200 to be maintained in perfect condition during the installation of the explosion-proof valve.

[0028] In this embodiment of the present invention, the main body 100 is racetrack-shaped, and the buffer groove 300 is also racetrack-shaped. The racetrack-shaped main body 100 and buffer groove 300 have a wide range of applications and can be applied to different batteries. Of course, the main body 100 and buffer groove 300 may be changed to other shapes according to actual needs, and similarly, the score 200 may also be changed to other shapes according to actual circumstances.

[0029] In embodiments of the present invention, the depth of the buffer groove 300 is greater than the depth of the score 200, and / or the width of the buffer groove 300 is greater than the width of the score 200. Specifically, in some examples, the depth of the buffer groove 300 is greater than the depth of the score 200, and the width of the buffer groove 300 is greater than the width of the score 200. This is because the buffer groove 300 primarily serves to protect the score 200, and if the width or depth of the buffer groove 300 is smaller than the score 200, it is difficult to achieve the corresponding technical effect. Therefore, in some examples, the depth of the buffer groove 300 is greater than the depth of the score 200, and the width of the buffer groove 300 is greater than the width of the score 200. Depending on the actual situation, it is also conceivable to make only the depth of the buffer groove 300 greater than the depth of the score 200, or only the width of the buffer groove 300 greater than the width of the score 200.

[0030] In embodiments of the present invention, as shown in Figures 2 to 7, the distance T1 between the bottom wall of the shallow groove 210 and the bottom wall of the main body 100, and the distance T3 between the bottom wall of the buffer groove 300 and the bottom wall of the main body 100 satisfy T3 > T1. Specifically, the distance between the bottom wall of the buffer groove 300 and the bottom wall of the main body 100 is greater than the distance between the bottom wall of the shallow groove 210 and the bottom wall of the main body 100, thereby preventing the buffer groove 300 from tearing in front of the shallow groove 210 and preventing the central portion of the main body 100 from popping out. However, since the deep groove 220 ruptures first in the explosion-proof valve, it is conceivable that the distance between the bottom wall of the buffer groove 300 and the bottom wall of the main body 100 may be less than or equal to the distance between the bottom wall of the shallow groove 210 and the bottom wall of the main body 100. However, in some examples, the distance between the bottom wall of the buffer groove 300 and the bottom wall of the main body 100 is greater than the distance between the bottom wall of the shallow groove 210 and the bottom wall of the main body 100.

[0031] In embodiments of the present invention, the length of the shallow groove 210 is 1 / 10 to 1 / 3 of the total length of the score 200. Specifically, as can be seen from the above, the deep groove 220 mainly ruptures to relieve pressure, so the shallow groove 210 cannot be made too long. If the shallow groove 210 is too long, it will affect the opening of the explosion-proof valve or increase the opening pressure of the explosion-proof valve. Therefore, based on experience and numerical calculations, in some examples, the length of the shallow groove 210 is about 1 / 10 to 1 / 3 of the total length of the score 200.

[0032] In one example, the score 200 in this embodiment is composed of one shallow groove 210 and one deep groove 220. That is, the score 200 in this embodiment cannot be composed of multiple shallow grooves 210 and deep grooves 220 spaced apart, and when the score 200 is composed of only one shallow groove 210 and one deep groove 220, the pressure relief effect is better and the manufacturing cost is lower.

[0033] In embodiments of the present invention, the cross-sectional shape of the shallow groove 210 is an inverted trapezoid, and / or the cross-sectional shape of the deep groove 220 is an inverted trapezoid. Specifically, by making the cross-sectional shape of the deep groove 220 an inverted trapezoid, the burst size of score 200 can be effectively improved, thereby improving the bursting effect. Since the shallow groove 210 does not need to burst, the cross-sectional shape of the shallow groove 210 can be set appropriately according to the actual situation. However, by designing the cross-sectional shapes of both the deep groove 220 and the shallow groove 210 to be inverted trapezoids, they can be produced using the same mold, thereby reducing production costs. For this reason, in some examples, the cross-sectional shapes of both the shallow groove 210 and the deep groove 220 are made to be inverted trapezoids.

[0034] In one example, the transition at the connection between the shallow groove 210 and the deep groove 220 is provided uniformly, thereby effectively reducing transition stress and improving the stability of the explosion-proof valve.

[0035] In embodiments of the present invention, the width of the top of the score 200 is 0.2 mm to 0.6 mm. Specifically, as can be seen from the above, in some examples, the cross-sectional shapes of the deep groove 220 and the shallow groove 210 are the same, so the width of the top of the score 200 includes both the width of the top of the deep groove 220 and the width of the top of the shallow groove 210. If the width of the top of the score 200 is too large, the stability of the explosion-proof valve deteriorates, and if the width of the top of the score 200 is too small, it similarly tends to affect the stability of the explosion-proof valve. Therefore, in some examples, the width is 0.2 mm to 0.6 mm, and within this range, the stability of the explosion-proof valve is good.

[0036] In the embodiment of the present invention, as shown in Figures 2 to 7, if the width of the top of the shallow groove 210 is W1 and the width of the top of the deep groove 220 is W2, then W1 = W2. Specifically, if the width of the top of the deep groove 220 and the width of the top of the shallow groove 210 are the same, production costs can be reduced, but this can be specifically adjusted according to the actual situation.

[0037] In embodiments of the present invention, the range of the distance T1 between the bottom wall of the shallow groove 210 and the bottom wall of the main body 100 is T1 = 30 μm to 100 μm. Specifically, as can be seen from Figures 3 and 6, the shallow groove 210 mainly serves to connect the outer periphery and the central part of the main body 100. Therefore, in some examples, the distance between the bottom wall of the shallow groove 210 and the bottom wall of the main body 100 is 30 μm to 100 μm. In this way, the stability of the explosion-proof valve can be guaranteed, and the rupture of the shallow groove 210 can be avoided.

[0038] In the embodiment of the present invention, the indentation directions of the score 200 and the buffer groove 300 in this embodiment may be the same or opposite. For example, in the drawing, the indentation directions of the score 200 and the buffer groove 300 are the same and both are indented downwards. However, depending on the actual situation, both the score 200 and the buffer groove 300 may be indented upwards, the score 200 may be indented downwards and the buffer groove 300 may be indented upwards, or the score 200 may be indented upwards and the buffer groove 300 may be indented downwards.

[0039] In embodiments of the present invention, the score 200 is provided on the outer circumference of the buffer groove 300, or the buffer groove 300 is provided on the outer circumference of the score 200. Specifically, in the configuration where the buffer groove 300 is provided on the outer circumference of the score 200, as shown in Figures 2 to 4, the buffer groove 300 can better protect the score 200 and improve the stability of the explosion-proof valve. In the configuration where the score 200 is provided on the outer circumference of the buffer groove 300, as shown in Figures 5 to 7, the size of the buffer groove 300 can be designed to be larger without affecting the size of the score 200, and at the same time, the opening area when the explosion-proof valve ruptures is also larger, so the pressure relief rate can be effectively improved and the risk of explosion during thermal runaway of the cell can be reduced. Either of the above two configurations can be selected depending on the actual situation.

[0040] Embodiments of the present invention further disclose a battery including a cover assembly and the explosion-proof valve described above, which is attached to the cover assembly. Since the battery of this embodiment includes the explosion-proof valve, it has at least all of the beneficial effects of the explosion-proof valve, which are omitted from this description.

[0041] In this specification, any description using terms such as “one embodiment,” “several embodiments,” “example,” “specific example,” or “several examples” means that the specific features, structures, materials, or properties described in the embodiment or example are included in at least one embodiment or example of the present invention. In this specification, the general expressions of the above terms do not necessarily refer to the same embodiment or example. Furthermore, the specific features, structures, materials, or properties described can be combined in an appropriate manner in any one or more embodiments or examples. In addition, those skilled in the art can combine or combine different embodiments or examples described herein.

[0042] Although embodiments of the present invention have been described in detail above with reference to the drawings, the present invention is not limited to the above embodiments, and various modifications can be made without departing from the spirit of the invention, within the scope of the knowledge of those skilled in the art. [Explanation of symbols]

[0043] Main unit 100, Score 200, shallow groove 210, deep groove 220 Buffer groove 300.

Claims

1. An explosion-proof valve comprising a body provided with a score and a buffer groove, wherein both the score and the buffer groove are racetrack shaped, The score includes deep grooves and shallow grooves, the depth of the shallow groove is D, and the distance between the bottom wall of the shallow groove and the bottom wall of the main body is T. １ The distance between the bottom wall of the deep groove and the bottom wall of the main body is T ２ And, The distance between the bottom wall of the buffer groove and the bottom wall of the main body is T ３ And, D > 0, T ３ >T ２ , T １ >T ２ That is, A valve characterized by its explosion-proof features.

2. The distance T between the bottom wall of the shallow groove portion and the bottom wall of the main body １ and the distance T between the bottom wall of the buffer groove and the bottom wall of the main body ３ are such that T ３ > T １ satisfies The explosion-proof valve according to feature 1.

3. The score is provided on the outer circumference of the buffer groove, or the buffer groove is provided on the outer circumference of the score. The explosion-proof valve according to feature 1.

4. The length of the shallow groove is 1 / 10 to 1 / 3 of the total length of the score. The explosion-proof valve according to feature 1.

5. The cross-sectional shape of the shallow groove is an inverted trapezoid, and / or the cross-sectional shape of the deep groove is an inverted trapezoid. The explosion-proof valve according to feature 1.

6. The width of the top of the aforementioned score is 0.2 mm to 0.6 mm. The explosion-proof valve according to feature 1.

7. The width of the top of the shallow groove is W １ The width of the top of the deep groove is W ２ And, W １ = W ２ That is, The explosion-proof valve according to feature 6.

8. The distance T between the bottom wall of the shallow groove and the bottom wall of the main body. １ The range of values ​​is T １ = 30 μm to 100 μm. The explosion-proof valve according to feature 1.

9. The depth of the buffer groove is greater than the depth of the score, and / or the width of the buffer groove is greater than the width of the score. The explosion-proof valve according to feature 1.

10. Includes an explosion-proof valve according to any one of claims 1 to 9, A battery characterized by the following features.

Images