Explosion-proof valve and battery

Abstract

An explosion-proof valve and a battery. The explosion-proof valve comprises a body (100), wherein the body (100) is provided with a tear line (200) and a relief groove (300), wherein the tear line (200) and the relief groove (300) are both racetrack-shaped; the tear line (200) comprises a deep groove section (220) and a shallow groove section (210); and the depth of the shallow groove section (210) is D, the distance between the bottom wall of the shallow groove section (210) and the bottom wall of the body (100) is T1, the distance between the bottom wall of the deep groove section (220) and the bottom wall of the body (100) is T2, and the distance between the bottom wall of the relief groove (300) and the bottom wall of the body (100) is T3, where D>0,T3>T2, and T1>T2. In the explosion-proof valve, the arrangement of the relief groove (300) can prevent fatigue cracking and failure of the tear line (200) due to excessive stress during cell production and pack assembly and under vehicle vibration conditions; the tear line (200) can fracture and open when the body (100) is subjected to pressure exceeding a preset pressure value, thereby ensuring pressure relief in a timely manner when the internal pressure of the cell abnormally increases due to thermal runaway; and the tear line (200) is in a racetrack shape and comprises a deep groove section (220) and a shallow groove section (210), which can effectively reduce the set opening pressure of the explosion-proof valve and reduce the manufacturing cost.

Description

An explosion-proof valve and battery

[0001] Relevant publicly available cross-references

[0002] This application claims priority to Chinese Patent Application No. 202420976935.2, filed on May 7, 2024, entitled “An Explosion-proof Valve and Battery”, the entire contents of which are incorporated herein by reference. Technical Field

[0003] This disclosure relates to the field of battery technology, and in particular to an explosion-proof valve and a battery. Background Technology

[0004] As a key functional component in batteries, explosion-proof valves provide excellent explosion protection, ensuring the safety of electric vehicles powered by batteries. The set opening pressure of explosion-proof valves varies depending on the battery model or function. Some batteries require lower set opening pressures for their explosion-proof valves, but limitations in manufacturing processes and other technologies result in higher production costs for these valves.

[0005] Summary of the Invention

[0006] This disclosure aims to at least address one of the technical problems existing in the prior art. To this end, this disclosure proposes an explosion-proof valve that can effectively reduce the manufacturing cost of explosion-proof valves with low opening pressure.

[0007] This disclosure also proposes a battery having the aforementioned explosion-proof valve.

[0008] The explosion-proof valve according to the first aspect of this disclosure includes:

[0009] The body is provided with grooves and buffer grooves, both of which are racetrack-shaped.

[0010] The groove includes a deep groove section and a shallow groove section. The depth of the shallow groove section is D, the distance between the bottom wall of the shallow groove section and the bottom wall of the main body is T1, and the distance between the bottom wall of the deep groove section and the bottom wall of the main body is T2.

[0011] The distance between the bottom wall of the buffer groove and the bottom wall of the main body is T3;

[0012] Where D > 0, T3 > T2, and T1 > T2.

[0013] The explosion-proof valve according to the embodiments of this disclosure has at least the following beneficial effects:

[0014] By setting buffer grooves, the stress on the grooves can be greatly reduced under conditions of cell production, pack assembly, and vehicle vibration, thereby preventing fatigue cracking failure caused by excessive stress on the grooves; the grooves can break and open when the body is subjected to pressure exceeding the preset pressure value, thereby ensuring timely pressure relief when the internal air pressure of the cell rises abnormally due to thermal runaway, preventing cell explosion; the grooves are racetrack-shaped and include deep groove sections and shallow groove sections, with the shallow groove section having a non-zero depth, which can effectively reduce the set opening pressure of the explosion-proof valve while reducing manufacturing costs.

[0015] According to some embodiments of this disclosure, the distance T1 between the bottom wall of the shallow trench section and the bottom wall of the main body and the distance T3 between the bottom wall of the buffer trench and the bottom wall of the main body satisfy: T3 > T1.

[0016] According to some embodiments of this disclosure, the groove is disposed on the outer periphery of the buffer groove, or the buffer groove is disposed on the outer periphery of the groove.

[0017] According to some embodiments of this disclosure, the length of the shallow groove segment accounts for 1 / 10 to 1 / 3 of the total length of the groove.

[0018] According to some embodiments of this disclosure, the cross-sectional shape of the shallow trench section is an inverted trapezoid, and / or the cross-sectional shape of the deep trench section is an inverted trapezoid.

[0019] According to some embodiments of this disclosure, the width of the top of the notch is 0.2 mm to 0.6 mm.

[0020] According to some embodiments of this disclosure, the top width of the shallow groove section is W1, and the top width of the deep groove section is W2, wherein W1 = W2.

[0021] According to some embodiments of this disclosure, the distance T1 between the bottom wall of the shallow trench section and the bottom wall of the main body ranges from 30 μm to 100 μm.

[0022] According to some embodiments of this disclosure, the depth of the buffer groove is greater than the depth of the groove, and / or the width of the buffer groove is greater than the width of the groove.

[0023] The battery according to the second aspect of this disclosure includes the aforementioned explosion-proof valve; since the battery includes the aforementioned explosion-proof valve, it has at least all 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 grooves during cell production, pack assembly, and vehicle vibration conditions, thereby preventing fatigue cracking failure due to excessive stress on the grooves; the grooves can break open when the body is subjected to pressure exceeding a preset pressure value, thereby ensuring timely pressure relief when the internal air pressure of the cell abnormally increases due to thermal runaway, preventing cell explosion; the grooves are racetrack-shaped and include deep groove sections and shallow groove sections, with the shallow groove section having a non-zero depth, effectively reducing the set opening pressure of the explosion-proof valve while reducing manufacturing costs.

[0024] Additional aspects and advantages of this disclosure will be set forth in part in the description which follows, and in part will be obvious from the description, or may be learned by practice of this disclosure. Attached Figure Description

[0025] The present disclosure will be further described below with reference to the accompanying drawings and embodiments, wherein:

[0026] Figure 1 is a schematic diagram of the structure of an explosion-proof valve according to a first aspect of this disclosure;

[0027] Figure 2 is a cross-sectional view of the first embodiment of the explosion-proof valve of this disclosure;

[0028] Figure 3 is an enlarged view of point A in Figure 2;

[0029] Figure 4 is an enlarged view of point B in Figure 2;

[0030] Figure 5 is a cross-sectional view of a second embodiment of the explosion-proof valve of this disclosure;

[0031] Figure 6 is an enlarged view of point C in Figure 5; and

[0032] Figure 7 is an enlarged view of point D in Figure 5.

[0033] Reference numerals: Body 100; Scratches 200, Shallow Groove Section 210, Deep Groove Section 220; Buffer Groove 300. Detailed Implementation

[0034] The embodiments of this disclosure are described in detail below, examples of which are illustrated in the accompanying drawings, wherein the same or similar reference numerals denote the same or similar elements or elements having the same or similar functions throughout. The embodiments described below with reference to the accompanying drawings are exemplary and are only used to explain this disclosure, and should not be construed as limiting this disclosure.

[0035] In the description of this disclosure, it should be understood that the orientation descriptions, such as up, down, etc., are based on the orientation or positional relationship shown in the accompanying drawings, and are only for the convenience of describing this disclosure and simplifying the description, and are not intended to indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation, and therefore should not be construed as a limitation of this disclosure.

[0036] In the description of this disclosure, "multiple" refers to two or more. The use of "first" and "second" is for the purpose of distinguishing technical features only and should not be construed as indicating or implying relative importance, or implicitly indicating the number of technical features indicated, or the order in which the technical features are indicated.

[0037] In the description of this disclosure, unless otherwise expressly defined, terms such as "setup," "installation," and "connection" should be interpreted broadly, and those skilled in the art can reasonably determine the specific meaning of the above terms in this disclosure in conjunction with the specific content of the technical solution.

[0038] As a key functional component in batteries, explosion-proof valves open when the internal pressure reaches a set pressure to release pressure and prevent battery explosion. However, current models suffer from high manufacturing costs due to the relatively low set pressure for battery explosion protection. To at least partially address these technical problems, this embodiment provides an explosion-proof valve that effectively reduces manufacturing costs for valves with lower set pressures. The explosion-proof valve of this embodiment is described in detail below with reference to the accompanying drawings.

[0039] Referring to Figures 1 to 7, the explosion-proof valve of this embodiment includes a body 100, on which a notch 200 and a buffer groove 300 are provided. The buffer groove 300 is used to reduce the stress on the notch 200 under cell production, pack assembly and vehicle vibration conditions, thereby preventing the notch 200 from fatigue cracking failure due to excessive stress. The notch 200 can break open when the body 100 is subjected to pressure above a preset pressure value, thereby ensuring timely pressure relief when the internal air pressure of the battery rises abnormally due to thermal runaway, and preventing battery explosion. The distance between the bottom wall of the notch 200 and the bottom wall of the body 100 affects the set pressure of the explosion-proof valve. Generally speaking, the greater the distance between the bottom wall of the notch 200 and the bottom wall of the body 100, the higher the opening pressure of the explosion-proof valve; the smaller the distance between the bottom wall of the notch 200 and the bottom wall of the body 100, the lower the opening pressure of the explosion-proof valve. When the explosion-proof valve needs to be set to a lower opening pressure, the distance between the bottom wall of the notch 200 and the bottom wall of the body 100 needs to be reduced. However, as the distance between the bottom wall of the notch 200 and the bottom wall of the body 100 decreases, the manufacturing precision will increase, leading to higher costs. At the same time, too small a distance between the bottom wall of the notch 200 and the bottom wall of the body 100 will also increase the difficulty of installing the entire explosion-proof valve and make the notch 200 position prone to damage.

[0040] To at least partially solve the aforementioned technical problems, the explosion-proof valve provided in this embodiment has the notch 200 made into a complete racetrack shape, and is divided into a deep groove section 220 and a shallow groove section 210 according to the different depths of the notch 200. 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 body 100 is less than the distance between the bottom wall of the shallow groove section 210 and the bottom wall of the body 100. Currently, most explosion-proof valves do not have a complete racetrack-shaped groove 200. Instead, they have a connecting part for connecting the outer periphery and the center of the body 100, and the thickness of the connecting part is basically the same as the thickness of the body 100. That is, the connecting part of a conventional explosion-proof valve is equivalent to the shallow groove section 210 in this embodiment, and the groove 200 of a conventional explosion-proof valve is equivalent to the deep groove section 220 in this embodiment. By making the groove 200 into a complete racetrack shape and dividing the groove 200 into a deep groove section 220 and a shallow groove section 210, the depth of the deep groove section 220 in this embodiment is the same as the depth of the conventional groove 200. Under the same conditions, 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 the conventional explosion-proof valve, the depth of the deep groove section 220 of the explosion-proof valve in this embodiment can be shallower than the depth of the groove 200 of the conventional explosion-proof valve, so the processing accuracy requirement is also lower, thereby effectively reducing the production cost; at the same time, the shallow groove section 210 can also play the same role as the connecting part of the conventional explosion-proof valve; when the deep groove section 220 cracks, the shallow groove section 210 can still be used to connect the outer peripheral part and the central part of the body 100, thereby preventing the central part of the body 100 from flying out and causing damage.

[0041] To facilitate understanding of the technical solution of this embodiment, referring to Figures 2 to 7, let the depth of the shallow trench section 210 be D, the distance between the bottom wall of the shallow trench section 210 and the bottom wall of the body 100 be T1, and the distance between the bottom wall of the deep trench section 220 and the bottom wall of the body 100 be T2. Then, we have: D > 0, T1 > T2.

[0042] In the embodiments of this disclosure, the distance between the bottom wall of the buffer groove 300 and the bottom wall of the body 100 is set to T3, where T3 > T2. This is to ensure that when the pressure inside the battery cell increases, the explosion-proof valve cracks at the mark 200 rather than at the buffer groove 300. It also allows the buffer groove 300 to have a better buffering effect, so that the mark 200 of the explosion-proof valve can remain intact during installation.

[0043] In the embodiments disclosed herein, the body 100 and the buffer groove 300 are both racetrack-shaped. The racetrack-shaped body 100 and buffer groove 300 have a wide range of applications and can be used with various different batteries. Of course, the body 100 and buffer groove 300 can also be changed to other shapes according to actual needs; similarly, the notch 200 can also be changed to other shapes according to actual needs.

[0044] In the embodiments of this disclosure, the depth of the buffer groove 300 is greater than the depth of the notch 200, and / or the width of the buffer groove 300 is greater than the width of the notch 200. Specifically, in some examples, the depth of the buffer groove 300 is greater than the depth of the notch 200 and the width of the buffer groove 300 is greater than the width of the notch 200, because the buffer groove 300 mainly serves to protect the notch 200. If the width or depth of the buffer groove 300 is less than that of the notch 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 notch 200 and the width of the buffer groove 300 is greater than the width of the notch 200. It is conceivable that, depending on the actual situation, only the depth of the buffer groove 300 may be greater than the depth of the notch 200, or only the width of the buffer groove 300 may be greater than the width of the notch 200.

[0045] In the embodiments of this disclosure, referring to Figures 2 to 7, the distance T1 between the bottom wall of the shallow groove section 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 the condition: T3 > T1. Specifically, the distance between the bottom wall of the buffer groove 300 and the bottom wall of the main body 100 being greater than the distance between the bottom wall of the shallow groove section 210 and the bottom wall of the main body 100 can prevent the buffer groove 300 from cracking before the shallow groove section 210, thereby preventing the central part of the main body 100 from flying out. However, it is conceivable that the explosion-proof valve cracks first in the deep groove section 220, so the distance between the bottom wall of the buffer groove 300 and the bottom wall of the main body 100 can also be equal to or less than the distance between the bottom wall of the shallow groove section 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 section 210 and the bottom wall of the main body 100.

[0046] In the embodiments of this disclosure, the length of the shallow groove section 210 accounts for 1 / 10 to 1 / 3 of the total length of the notch 200. Specifically, as mentioned above, the deep groove section 220 is mainly responsible for burst pressure relief. Therefore, the shallow groove section 210 cannot be too long. If the shallow groove section 210 is too long, it will affect the opening of the explosion-proof valve or cause the opening pressure of the explosion-proof valve to increase. Therefore, based on experience and numerical calculations, in some examples, the length of the shallow groove section 210 accounts for only 1 / 10 to 1 / 3 of the total length of the notch 200.

[0047] In one example, the groove 200 in this embodiment is composed of a shallow groove segment 210 and a deep groove segment 220. That is, the groove 200 in this embodiment cannot be composed of multiple shallow groove segments 210 and deep groove segments 220 that are spaced apart. The pressure relief effect is better and the manufacturing cost is lower when the groove 200 is composed of only a shallow groove segment 210 and a deep groove segment 220.

[0048] In the embodiments of this disclosure, the cross-sectional shape of the shallow groove section 210 is an inverted trapezoid, and / or the cross-sectional shape of the deep groove section 220 is an inverted trapezoid. Specifically, setting the cross-section of the deep groove section 220 to an inverted trapezoid can effectively increase the burst size of the notch 200, thereby improving the bursting effect. Since the shallow groove section 210 does not need to burst, the shallow groove section 210 can be set with a suitable cross-sectional shape according to the actual situation. However, designing the cross-sections of both the deep groove section 220 and the shallow groove section 210 to be inverted trapezoids allows for production using the same mold, thereby reducing production costs. Therefore, in some examples, the cross-sectional shapes of both the shallow groove section 210 and the deep groove section 220 are set to inverted trapezoids.

[0049] In one example, the connection between the shallow groove section 210 and the deep groove section 220 is set with a uniform transition, which can effectively reduce the transition stress and thus improve the stability of the explosion-proof valve.

[0050] In the embodiments of this disclosure, the width of the top of the notch 200 is 0.2mm to 0.6mm. Specifically, as described above, in some examples, the deep groove section 220 and the shallow groove section 210 have the same cross-sectional shape. Therefore, the width of the top of the notch 200 includes both the width of the top of the deep groove section 220 and the width of the top of the shallow groove section 210. If the width of the top of the notch 200 is too large, it will lead to a decrease in the stability of the explosion-proof valve. If the width of the top of the notch 200 is too small, it will also easily affect the stability of the explosion-proof valve. Therefore, in some examples, its width is 0.2mm to 0.6mm. Within this range, the stability of the explosion-proof valve is better.

[0051] In the embodiments of this disclosure, referring to Figures 2 to 7, the top width of the shallow groove section 210 is W1, and the top width of the deep groove section 220 is W2, where W1 = W2. Specifically, having the same top width for the deep groove section 220 and the shallow groove section 210 can reduce production costs, but it can also be adjusted according to actual circumstances.

[0052] In the embodiments of this disclosure, the distance T1 between the bottom wall of the shallow groove section 210 and the bottom wall of the body 100 ranges from 30 μm to 100 μm. Specifically, referring to Figures 3 and 6, as can be seen from the above, the shallow groove section 210 mainly serves to connect the outer periphery and the central part of the body 100. Therefore, in some examples, the distance between the bottom wall of the shallow groove section 210 and the bottom wall of the body 100 is 30 μm to 100 μm. This ensures the stability of the explosion-proof valve while preventing the shallow groove section 210 from bursting.

[0053] In the embodiments of this disclosure, the recessed directions of the notch 200 and the buffer groove 300 can be the same or opposite. For example, the recessed directions of the notch 200 and the buffer groove 300 shown in the figures are the same and both are recessed downwards. However, depending on the actual situation, the notch 200 and the buffer groove 300 can be designed to be recessed upwards, or the notch 200 can be recessed downwards and the buffer groove 300 can be recessed upwards, or the notch 200 can be recessed upwards and the buffer groove 300 can be recessed downwards.

[0054] In the embodiments of this disclosure, the notch 200 is disposed on the outer periphery of the buffer groove 300, or the buffer groove 300 is disposed on the outer periphery of the notch 200. Specifically, as shown in Figures 2 to 4, the buffer groove 300 is disposed on the outer periphery of the notch 200, which provides better protection for the notch 200 and thus improves the stability of the explosion-proof valve. As shown in Figures 5 to 7, the notch 200 is disposed on the outer periphery of the buffer groove 300, which allows the buffer groove 300 to be designed to be larger without affecting the size of the notch 200. Simultaneously, the opening area of ​​the explosion-proof valve is also larger when it bursts, thus effectively increasing the pressure relief rate and reducing the risk of explosion during thermal runaway of the battery cell. Either of the above two solutions can be selected according to the actual situation.

[0055] This disclosure also discloses a battery, which includes a cover assembly and the aforementioned explosion-proof valve, the explosion-proof valve being installed on the cover assembly. Since the battery of this embodiment includes the aforementioned explosion-proof valve, it possesses at least all the beneficial effects of the explosion-proof valve, which will not be elaborated upon here.

[0056] In the description of this specification, the references to terms such as "one embodiment," "some embodiments," "example," "specific example," or "some examples," etc., indicate that a specific feature, structure, material, or characteristic described in connection with that embodiment or example is included in at least one embodiment or example of this disclosure. In this specification, the illustrative expressions of the above terms do not necessarily refer to the same embodiment or example. Furthermore, the specific features, structures, materials, or characteristics described may be combined in any suitable manner in one or more embodiments or examples. In addition, those skilled in the art can combine and integrate the different embodiments or examples described in this specification.

[0057] The embodiments of this disclosure have been described in detail above with reference to the accompanying drawings. However, this disclosure is not limited to the above embodiments. Within the scope of knowledge possessed by those skilled in the art, various changes can be made without departing from the spirit of this disclosure.

Claims

1. An explosion-proof valve, comprising: The body is provided with grooves and buffer grooves, both of which are racetrack-shaped. The groove includes a deep groove section and a shallow groove section. The depth of the shallow groove section is D, the distance between the bottom wall of the shallow groove section and the bottom wall of the main body is T1, and the distance between the bottom wall of the deep groove section 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; Where D > 0, T3 > T2, and T1 > T2.

2. The explosion-proof valve according to claim 1, wherein, The distance T1 between the bottom wall of the shallow trench section and the bottom wall of the main body and the distance T3 between the bottom wall of the buffer trench and the bottom wall of the main body satisfy: T3 > T1.

3. The explosion-proof valve according to claim 1, wherein, The groove is located on the outer periphery of the buffer groove, or the buffer groove is located on the outer periphery of the groove.

4. The explosion-proof valve according to claim 1, wherein, The length of the shallow groove segment accounts for 1 / 10 to 1 / 3 of the total length of the groove.

5. The explosion-proof valve according to claim 1, wherein, The shallow trench section has an inverted trapezoidal cross-sectional shape, and / or the deep trench section has an inverted trapezoidal cross-sectional shape.

6. The explosion-proof valve according to claim 1, wherein, The width of the top of the notch is 0.2mm to 0.6mm.

7. The explosion-proof valve according to claim 6, wherein, The top width of the shallow trench section is W1, and the top width of the deep trench section is W2, where W1 = W2.

8. The explosion-proof valve according to claim 1, wherein, The distance T1 between the bottom wall of the shallow trench section and the bottom wall of the main body has a range of 30μm to 100μm.

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

10. A battery comprising an explosion-proof valve as described in any one of claims 1 to 9.

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