Top cover assembly and battery monomer

Abstract

The utility model discloses a top cover assembly and a battery monomer, the top cover assembly comprises: a cover body, which is provided with a mounting hole penetrating through the cover body in the thickness direction of the cover body; the anti-explosion valve is arranged in the mounting hole and connected with the cover body in an interference fit mode. According to the top cover assembly provided by the embodiment of the utility model, the explosion-proof valve is arranged in the mounting hole and is in interference fit connection with the cover body, so that the explosion-proof valve is mounted, and the firmness of the assembled explosion-proof valve is ensured through pressure generated by interference fit of the explosion-proof valve and the cover body, so that the integrity of the explosion-proof valve and the sealing effect of the cover plate assembly are ensured; and the safety of the battery cell applying the cover plate assembly is improved.

Description

Technical Field

[0001] The utility model relates to the technical field of batteries, in particular to a top cover assembly and a battery cell. Background Art

[0002] With the increasing maturity of lithium-ion battery technology, lithium-ion batteries are widely used as power batteries in electric vehicles and energy storage fields, and the requirements for the use performance and safety of lithium-ion batteries are increasing day by day. The top cover is a key component in a lithium-ion battery, and its functions include welding with the housing to form a sealed cavity, leading out the positive and negative electrodes of the electrode group, and serving as an assembly carrier, etc.

[0003] The explosion-proof valve on the top cover is an important component structure to ensure the safety of the battery cell. It prevents explosion by automatically releasing the excessive pressure inside the battery cell. In the prior art, the explosion-proof valve is usually fixedly connected to the top cover by welding. However, defects such as thermal expansion and contraction and welding explosion points caused by welding connection are likely to lead to problems such as thinning of the notch of the explosion-proof valve, cracking of the top cover or the explosion-proof valve, thus affecting the safety of the battery cell. Summary of the Utility Model

[0004] The utility model aims to solve at least one of the technical problems existing in the prior art. For this purpose, the utility model provides a top cover assembly, which ensures the integrity of the explosion-proof valve and the sealing effect of the cover plate assembly, and improves the safety of the battery cell using the cover plate assembly of the present application.

[0005] The utility model also provides a battery cell, which includes the above-mentioned top cover assembly.

[0006] The top cover assembly according to the embodiment of the utility model is used for a battery cell, and includes: a cover body, which has a mounting hole penetrating the cover body in the thickness direction of the cover body; an explosion-proof valve, which is arranged in the mounting hole and is connected with the cover body in an interference fit manner.

[0007] The top cover assembly according to the embodiment of the utility model includes a cover body and an explosion-proof valve. The cover body has a mounting hole penetrating the cover body in the thickness direction of the cover body. The explosion-proof valve is arranged in the mounting hole and is connected with the cover body in an interference fit manner, so as to realize the installation of the explosion-proof valve. And the pressure generated by the interference fit between the explosion-proof valve and the cover body ensures the firmness of the explosion-proof valve after assembly, thereby ensuring the integrity of the explosion-proof valve and the sealing effect of the cover plate assembly, and improving the safety of the battery cell using the cover plate assembly of the present application.

[0008] In some embodiments of the utility model, the outer peripheral wall of the explosion-proof valve has a boss, the inner wall of the mounting hole has a mounting groove, the boss is located in the mounting groove and at least part of the boss is connected with the inner wall of the mounting groove in an interference fit manner.

[0009] In some embodiments of the present invention, along the circumferential direction of the mounting hole, the interference between the boss and the side wall of the mounting groove is 0.02 mm-0.05 mm.

[0010] In some embodiments of the present invention, a gap between an end of the boss away from the center of the mounting hole and an end of the mounting groove away from the center of the mounting hole is 0.02 mm-0.1 mm.

[0011] In some embodiments of the present invention, the surface of the boss facing the pole group of the battery cell is flush with the surface of the cover body facing the pole group; and / or, along the thickness direction of the cover body, the depth of the mounting hole is greater than the thickness of the explosion-proof valve.

[0012] In some embodiments of the present utility model, there are multiple bosses, and the multiple bosses are arranged along the circumferential direction of the explosion-proof valve, and there are multiple mounting grooves corresponding to the bosses one by one.

[0013] In some embodiments of the utility model, a support portion is provided at one end of the mounting hole away from the pole group of the battery cell, and the support portion protrudes toward the center direction of the mounting hole. The top cover assembly also includes a sealing ring, the explosion-proof valve is located on the side of the support portion facing the pole group, and the sealing ring is located between the support portion and the explosion-proof valve.

[0014] In some embodiments of the present invention, the top cover assembly further includes: a protective film, wherein the protective film is covered on a side of the mounting hole away from the pole group.

[0015] In some embodiments of the present invention, a notch groove is provided on the explosion-proof valve, and the notch groove is located on a side of the interference fit connection between the explosion-proof valve and the cover body toward the center of the mounting hole.

[0016] A battery cell according to an embodiment of the present invention includes the above-mentioned top cover assembly.

[0017] According to the battery cell of the embodiment of the utility model, a top cover assembly is provided, and the top cover assembly includes a cover body and an explosion-proof valve. The cover body has a mounting hole which penetrates the cover body in the thickness direction of the cover body. The explosion-proof valve is arranged in the mounting hole and is connected with the cover body by interference fit, so as to realize the installation of the explosion-proof valve. The pressure generated by the interference fit between the explosion-proof valve and the cover body ensures the firmness of the explosion-proof valve after assembly, thereby ensuring the integrity of the explosion-proof valve and the sealing effect of the cover assembly, thereby improving the safety of the applied battery cell.

[0018] Additional aspects and advantages of the present invention will be given in part in the following description, and in part will become apparent from the following description, or will be learned through the practice of the present invention. Description of the Drawings

[0019] The above and / or additional aspects and advantages of the present utility model will become apparent and be readily understood from the description of the embodiments in conjunction with the following drawings, where:

[0020] Figure 1 is an exploded view of a top cover assembly according to an embodiment of the present utility model;

[0021] Figure 2 is a front view of a top cover assembly according to an embodiment of the present utility model;

[0022] Figure 3 is a cross-sectional view of a top cover assembly according to an embodiment of the present utility model;

[0023] Figure 4 is Figure 3 an enlarged view at P in

[0024] Figure 5 is a structural diagram of a cover body according to an embodiment of the present utility model;

[0025] Figure 6 is a front view of a cover body according to an embodiment of the present utility model;

[0026] Figure 7 is a structural diagram of an explosion-proof valve according to an embodiment of the present utility model;

[0027] Figure 8 is a front view of an explosion-proof valve according to an embodiment of the present utility model.

[0028] Reference Signs:

[0029] 100, top cover assembly;

[0030] 1, cover body; 11, mounting hole; 111, mounting groove; 112, support portion;

[0031] 2, explosion-proof valve; 21, boss; 22, scoring groove;

[0032] 3, sealing ring;

[0033] 4, protective film. Detailed Description of the Embodiments

[0034] The embodiments of the present utility model will be described in detail below. Examples of the embodiments are shown in the drawings, where 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 by referring to the drawings are exemplary only for explaining the present utility model and should not be construed as limiting the present utility model.

[0035] In the description of the present utility model, it should be understood that the orientation or positional relationship indicated by terms such as "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 therefore should not be construed as a limitation to the present utility model. In addition, features defined as "first", "second" may explicitly or implicitly include one or more of such features. In the description of the present utility model, unless otherwise specified, the meaning of "a plurality" is two or more.

[0036] In the description of the present utility model, it should be noted that, unless otherwise clearly specified and defined, the terms "installation", "connection", "coupling" should be understood in a broad sense. For example, it may be a fixed connection, a detachable connection, or an integral connection; it may be a mechanical connection or an electrical connection; it may be directly connected or indirectly connected through an intermediate medium, and it may be the communication inside two elements. 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.

[0037] The top cover assembly 100 according to an embodiment of the present utility model will be described below with reference to the drawings.

[0038] As Figures 1-8 shown, the top cover assembly 100 according to an embodiment of the present utility model is for a battery cell. The top cover assembly 100 includes a cover body 1 and an explosion-proof valve 2. Among them, the cover body 1 has a mounting hole 11 penetrating the cover body 1 in the thickness direction of the cover body 1, and the explosion-proof valve 2 is disposed in the mounting hole 11 and is connected to the cover body 1 by interference fit.

[0039] Thus, by disposing the explosion-proof valve 2 in the mounting hole 11 and connecting it to the cover body 1 by interference fit, the installation of the explosion-proof valve 2 is realized. At the same time, the pressure generated by the interference fit between the explosion-proof valve 2 and the cover body 1 ensures the firmness of the explosion-proof valve 2 after assembly, and can offset part of the external vibration and impact, thereby ensuring the integrity of the explosion-proof valve 2 and the sealing effect of the cover plate assembly, improving the sealing yield, effectively avoiding the influence of the welding connection between the explosion-proof valve 2 and the cover body 1 on the performance of the explosion-proof valve 2 in the prior art, and further improving the safety of the battery cell using the cover plate assembly of the present application.

[0040] Optionally, the cover body 1 is a bright aluminum sheet.

[0041] According to the top cover assembly 100 of the embodiment of the utility model, the top cover assembly 100 includes a cover body 1 and an explosion-proof valve 2. The cover body 1 has a mounting hole 11 that penetrates the cover body 1 in the thickness direction of the cover body 1. The explosion-proof valve 2 is arranged in the mounting hole 11 and is connected with the cover body 1 by interference fit, so as to achieve the installation of the explosion-proof valve 2. The pressure generated by the interference fit between the explosion-proof valve 2 and the cover body 1 ensures the firmness of the explosion-proof valve 2 after assembly, thereby ensuring the integrity of the explosion-proof valve 2 and the sealing effect of the cover assembly, thereby improving the safety of the battery cell to which the cover assembly of the present application is applied.

[0042] In some embodiments of the present invention, Figures 4-8 As shown, the outer peripheral wall of the explosion-proof valve 2 has a boss 21, the inner wall of the mounting hole 11 has a mounting groove 111, the boss 21 is located in the mounting groove 111, and at least a portion of the boss 21 is connected by interference fit with the inner wall of the mounting groove 111. Thus, by the boss 21 being located in the mounting groove 111 and at least a portion of the boss 21 being connected by interference fit with the inner wall of the mounting groove 111, the explosion-proof valve 2 is arranged in the mounting hole 11 and connected by interference fit with the cover body 1.

[0043] In some embodiments of the present invention, Figures 4-8 As shown, along the circumferential direction of the mounting hole 11, the interference between the boss 21 and the side wall of the mounting groove 111 is 0.02mm-0.05mm. Thus, the explosion-proof valve 2 is fixed by the interference fit between the boss 21 and the side wall of the mounting groove 111, and the value of the interference is limited to ensure the connection strength of the interference fit between the explosion-proof valve 2 and the cover body 1, thereby improving the reliability of the cover assembly. Optionally, the interference between the boss 21 and the side wall of the mounting groove 111 is 0.02mm, 0.025mm, 0.03mm, 0.035mm, 0.04mm, 0.045mm or 0.05mm.

[0044] Furthermore, along the circumferential direction of the mounting hole 11, the minimum dimension of the boss 21 is a, the maximum dimension of the mounting groove 111 is b, and the interference amount is bc. Thus, the boss 21 is connected to the side wall of the mounting groove 111 by interference fit through such restrictions.

[0045] In some embodiments of the present invention, Figures 4-8 As shown, the gap between the end of the boss 21 away from the center of the mounting hole 11 and the end of the mounting groove 111 away from the center of the mounting hole 11 is 0.02 mm-0.1 mm.

[0046] It is understandable that after the explosion-proof valve 2 is assembled, the explosion-proof valve 2 is fixed by the interference fit between the boss 21 and the side wall of the mounting groove 111, and the end of the boss 21 away from the center of the mounting hole 11 is separated from the end of the mounting groove 111 away from the center of the mounting hole 11, which effectively prevents the explosion-proof valve 2 or the boss 21 from deforming toward the center of the mounting hole 11, thereby ensuring the reliability of the explosion-proof valve 2. At the same time, by limiting the size of the gap between the end of the boss 21 away from the center of the mounting hole 11 and the end of the mounting groove 111 away from the center of the mounting hole 11, the reliability of the connection of the explosion-proof valve 2 is ensured.

[0047] Optionally, the gap between one end of the boss 21 away from the center of the mounting hole 11 and one end of the mounting groove 111 away from the center of the mounting hole 11 is 0.02mm, 0.025mm, 0.03mm, 0.035mm, 0.04mm, 0.045mm, 0.05mm, 0.55mm, 0.06mm, 0.065mm, 0.07mm, 0.075mm, 0.08mm, 0.085mm, 0.09mmmm, 0.095mm or 0.1mm.

[0048] Furthermore, the dimension between the end of the boss 21 away from the center of the mounting hole 11 and the end of the boss 21 close to the center of the mounting hole 11 is d, the dimension between the end of the mounting groove 111 away from the center of the mounting hole 11 and the end of the mounting groove 111 close to the center of the mounting hole 11 is e, and the gap between the end of the boss 21 away from the center of the mounting hole 11 and the end of the mounting groove 111 away from the center of the mounting hole 11 is f, f = ed. Thus, the gap between the end of the boss 21 away from the center of the mounting hole 11 and the end of the mounting groove 111 away from the center of the mounting hole 11 is limited in this way.

[0049] In some embodiments of the present invention, Figures 4-8 As shown, there are multiple bosses 21, and the multiple bosses 21 are arranged along the circumferential direction of the explosion-proof valve 2, and there are multiple mounting grooves 111 corresponding to the bosses 21. It can be understood that at least part of each boss 21 located in the mounting groove 111 is connected with the inner wall of the mounting groove 111 by interference fit, thereby, through the cooperation of the multiple bosses 21 and the multiple mounting grooves 111, the interference fit connection between the explosion-proof valve 2 and the cover body 1 is further ensured, and the firmness of the assembly of the explosion-proof valve 2 is ensured.

[0050] In some embodiments of the present invention, Figure 3 and Figure 4As shown, the surface of the boss 21 facing the electrode group of the battery cell is flush with the surface of the cover body 1 facing the electrode group. It can be understood that the top cover assembly 100 is connected to the housing of the battery cell to form a sealed space, and the electrode group is located in the sealed space. Thus, by making the surface of the boss 21 facing the electrode group of the battery cell flush with the surface of the cover body 1 facing the electrode group, the reliability of the top cover assembly 100 is improved, and the assembly of the battery cell is facilitated.

[0051] In some embodiments of the present invention, as Figure 3 and Figure 4 shown, along the thickness direction of the cover body 1, the depth of the mounting hole 11 is greater than the thickness of the explosion-proof valve 2. It can be understood that in order to ensure the sealing between the cover body 1 and the explosion-proof valve 2, a seal 3 is provided between the cover body 1 and the explosion-proof valve 2, and the explosion-proof valve 2 is connected to the cover body 1 by interference fit to squeeze the sealing ring 3, so as to fix the sealing ring 3 and ensure the sealing effect of the sealing ring 3. Thus, along the thickness direction of the cover body 1, by making the depth of the mounting hole 11 greater than the thickness of the explosion-proof valve 2, after the sealing ring 3 is located between the cover body 1 and the explosion-proof valve 2, the surface of the boss 21 facing the electrode group of the battery cell is flush with the surface of the cover body 1 facing the electrode group, thereby improving the reliability of the battery cell applying the top cover assembly 100.

[0052] In some embodiments of the present invention, as Figures 3-8 shown, a support portion 112 is provided at one end of the mounting hole 11 facing away from the electrode group of the battery cell. The support portion 112 protrudes towards the center direction of the mounting hole 11. The top cover assembly 100 further includes a sealing ring 3. The explosion-proof valve 2 is located on the side of the support portion 112 facing the electrode group, and the sealing ring 3 is located between the support portion 112 and the explosion-proof valve 2.

[0053] It can be understood that by arranging the explosion-proof valve 2 in the mounting hole 11 and connecting it to the cover body 1 by interference fit, and the sealing ring 3 is located between the support portion 112 and the explosion-proof valve 2, so that both the explosion-proof valve 2 and the support portion 112 squeeze the sealing ring 3, thereby improving the sealing effect of the sealing ring 3 on the gap between the support portion 112 and the explosion-proof valve 2, further preventing internal leakage of the battery cell, and thus extending the service life of the battery cell. At the same time, the support portion 112 provides an installation point for the assembly of the sealing ring 3, reduces the assembly difficulty of the sealing ring 3, and further ensures the sealing effect of the sealing ring 3.

[0054] In some embodiments of the present invention, as Figure 5 and Figure 5 shown, the support portion 112 is an annular structure extending along the circumferential direction of the mounting hole 11. Thus, through such a setting, the support effect of the support portion 112 on the sealing ring 3 is further improved, the assembly difficulty of the sealing ring 3 is further reduced, and the sealing effect of the sealing ring 3 is further ensured.

[0055] In some embodiments of the present utility model, such as Figure 1 , Figure 3 and Figure 4 shown, the top cover assembly 100 further includes a protective film 4. Wherein, the protective film 4 is covered on the side of the mounting hole 11 facing away from the electrode group. It can be understood that after the battery cell is assembled, the protective film 4 can effectively prevent external impurities from entering the mounting hole 11 and affecting the performance of the explosion-proof valve 2, further improving the reliability of the top cover assembly 100.

[0056] In some embodiments of the present utility model, such as Figure 4 , Figure 7 and Figure 8 shown, the explosion-proof valve 2 is provided with a scoring groove 22, and the scoring groove 22 is located on the side of the interference fit connection between the explosion-proof valve 2 and the cover body 1 facing the center of the mounting hole 11. Thus, the scoring groove 22 is the weakest part of the explosion-proof valve 2, so that the explosion-proof valve 2 ruptures from the scoring groove 22 when it explodes, thereby guiding the release of the blasting pressure, avoiding the irregular distribution and release of pressure inside the explosion-proof valve 2, and effectively improving the safety and reliability of the explosion-proof valve 2. At the same time, since the structural strength of the interference fit connection between the explosion-proof valve 2 and the cover body 1 is relatively strong, by locating the scoring groove 22 on the side of the interference fit connection between the explosion-proof valve 2 and the cover body 1 facing the center of the mounting hole 11, it is further ensured that the explosion-proof valve 2 ruptures from the scoring groove 22 when it explodes, improving the reliability of the top cover assembly 100.

[0057] The battery cell of the embodiment of the present utility model will be described below.

[0058] The battery cell according to the embodiment of the present utility model includes a top cover assembly 100.

[0059] The battery cell according to the embodiment of the present utility model is provided with a top cover assembly 100. The top cover assembly 100 includes a cover body 1 and an explosion-proof valve 2. The cover body 1 has a mounting hole 11 that penetrates the cover body 1 in the thickness direction of the cover body 1. The explosion-proof valve 2 is arranged in the mounting hole 11 and is connected with the cover body 1 in an interference fit manner to realize the installation of the explosion-proof valve 2, and the firmness of the explosion-proof valve 2 after assembly is ensured by the pressure generated by the interference fit between the explosion-proof valve 2 and the cover body 1, thereby ensuring the integrity of the explosion-proof valve 2 and the sealing effect of the cover plate assembly, and improving the safety of the applied battery cell.

[0060] The other components of the battery cell according to the embodiment of the present utility model are known to those of ordinary skill in the art and will not be described in detail here.

[0061] In the description of this specification, the descriptions referring to terms such as "one embodiment", "some embodiments", "schematic embodiments", "examples", "specific examples", 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 expressions 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.

[0062] Although the embodiments of the present utility model have been shown and described, those of ordinary skill in the art can understand that various changes, modifications, substitutions, and variations can be made to these embodiments without departing from the principles and spirit of the present utility model, and the scope of the present utility model is defined by the claims and their equivalents.

Claims

1. A top cover assembly, characterized in that: For battery cells, including: A cover body, wherein the cover body has a mounting hole penetrating the cover body in a thickness direction of the cover body; An explosion-proof valve is arranged in the mounting hole and is connected to the cover body by interference fit. The outer peripheral wall of the explosion-proof valve has a boss, and the inner wall of the mounting hole has a mounting groove. The boss is located in the mounting groove and at least a portion of the boss is connected to the inner wall of the mounting groove by interference fit.

2. The top cover assembly according to claim 1, characterized in that: Along the circumferential direction of the mounting hole, the interference between the boss and the side wall of the mounting groove is 0.02mm-0.05mm.

3. The top cover assembly according to claim 2, characterized in that: A gap between an end of the boss away from the center of the mounting hole and an end of the mounting groove away from the center of the mounting hole is 0.02 mm-0.1 mm.

4. The top cover assembly according to claim 1, characterized in that: The surface of the boss facing the electrode group of the battery cell is flush with the surface of the cover body facing the electrode group; And / or, along the thickness direction of the cover body, the depth of the mounting hole is greater than the thickness of the explosion-proof valve.

5. The top cover assembly according to claim 1, characterized in that: There are a plurality of bosses, which are arranged along the circumferential direction of the explosion-proof valve, and there are a plurality of mounting grooves corresponding one to one with the bosses.

6. The top cover assembly according to claim 1, characterized in that: A support portion is provided at one end of the mounting hole away from the pole group of the battery cell, and the support portion protrudes toward the center direction of the mounting hole. The top cover assembly also includes a sealing ring, and the explosion-proof valve is located on the side of the support portion facing the pole group, and the sealing ring is located between the support portion and the explosion-proof valve.

7. The top cover assembly according to claim 6, characterized in that: The top cover assembly also includes: A protective film is provided to cover a side of the mounting hole away from the pole group.

8. The top cover assembly according to claim 1, characterized in that: The explosion-proof valve is provided with a notched groove, and the notched groove is located on a side of the interference fit connection between the explosion-proof valve and the cover body toward the center of the mounting hole.

9. A battery cell, characterized in that: Comprising a top cover assembly according to any one of claims 1-8.

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