Battery shell and battery

Abstract

The utility model belongs to the technical field of batteries, and discloses a battery shell and a battery, the battery shell comprises a shell body and an anti-explosion valve, the shell body comprises a first wall surface provided with a mounting hole, the anti-explosion valve comprises a plugging part and a connecting part, the connecting part is positioned outside the shell body and is abutted against the outer side of the first wall surface, and the first wall surface is provided with a second wall surface; the connecting part and the shell body are connected in a penetration welding mode, the flatness of the surface, facing the first wall face, of the connecting part is not larger than 0.2 mm, and the flatness of the surface, facing the connecting part, of the first wall face is not larger than 0.3 mm. According to the explosion-proof valve shell, the connecting part and the first wall face are overlapped in space, a penetration welding mode is adopted, an extra welding area does not need to be reserved, and therefore it is guaranteed that the explosion-proof valve has the enough opening area, meanwhile, it is guaranteed that the enough welding area exists between the explosion-proof valve and the shell body, the welding difficulty is reduced, and the welding efficiency is improved. And in addition, the attaching flatness is limited, and the undesirable phenomena of pseudo soldering, welding holes and the like are avoided.

Description

Technical Field

[0001] This utility model relates to the field of battery technology, and in particular to a battery casing and a battery. Background Technology

[0002] The battery casing is an indispensable component of a battery. It not only protects the battery from physical damage but also ensures the safe operation of the battery system. To improve the safety performance of individual battery cells, explosion-proof valves are typically installed on the cell's cover. When the explosion-proof valve opens due to thermal runaway of the cell, there is a risk of fire and explosion due to the interaction between the circuit components and the explosion-proof valve, as they are located on the same side. Therefore, currently, the explosion-proof valve is placed on the side wall of the casing to address the problem of mutual interference between the explosion-proof valve and the circuit components.

[0003] In order to ensure smooth opening, explosion-proof valves need to have sufficient area. However, due to the limited installation area that the side wall of the shell can provide for the explosion-proof valve, the area for welding the explosion-proof valve to the side wall of the shell is relatively narrow. This not only makes welding difficult, but also results in poor strength and airtightness after welding. Utility Model Content

[0004] The purpose of this utility model is to provide a battery casing and battery that are easy to weld, have high welding strength, and good weld airtightness.

[0005] To achieve this objective, the present invention adopts the following technical solution:

[0006] On one hand, a battery housing is provided, the battery housing comprising:

[0007] The battery casing includes:

[0008] The outer casing body includes a first wall surface, on which mounting holes are provided;

[0009] An explosion-proof valve, comprising a plugging part and a connecting part, wherein the plugging part is inserted into the mounting hole, the connecting part is located outside the outer shell and abuts against the outer side of the first wall surface, and the connecting part is connected to the outer shell by a through weld.

[0010] The flatness of the surface of the connecting part facing the first wall surface does not exceed 0.2 mm, and the flatness of the surface of the first wall surface facing the connecting part does not exceed 0.3 mm.

[0011] Optionally, the thickness of the connecting portion along the first direction is T1, satisfying 0.3mm≤T1≤1mm.

[0012] Optionally, the width of the overlap between the connecting portion and the first wall surface along the second direction is L1, and satisfies 0.5mm≤L1≤1.5mm.

[0013] Optionally, the explosion-proof valve has a first groove on the side opposite to the first wall surface.

[0014] Optionally, the explosion-proof valve may also have a second groove located within the first groove.

[0015] Optionally, the width dimension of the mounting hole along the second direction is S, the width dimension of the first groove along the second direction is S1, and the width dimension of the second groove along the second direction is S2, and satisfies 2mm≤(S-S1) / 2≤(S-S2) / 2.

[0016] Optionally, the explosion-proof valve also has a weakening structure, which is disposed in the second groove.

[0017] Optionally, the weakening structure is a groove extending along a first direction, and the thickness of the second groove where the groove is formed is less than the thickness of the second groove where the groove is not formed.

[0018] Optionally, the thickness of the first wall surface along the first direction is T2, which satisfies 0.15mm≤T2≤2mm.

[0019] On the other hand, a battery is provided, the battery including a cover plate, an electrode assembly, and a battery casing as described in any of the preceding claims, the cover plate covering the opening of the battery casing and closing the battery casing to form a receiving cavity for accommodating the electrode assembly.

[0020] The beneficial effects of this utility model are:

[0021] This utility model provides a battery casing, which includes an explosion-proof valve composed of a sealing part and a connecting part. By inserting the sealing part of the explosion-proof valve into the mounting hole on the first wall surface of the casing body, and using a through-welding method to connect the connecting part to the outside of the first wall surface, not only is there spatial overlap between the connecting part and the first wall surface, improving space utilization, but also the use of through-welding eliminates the need to reserve an additional welding area. This ensures that the explosion-proof valve has a sufficient opening area while also ensuring sufficient welding area between the explosion-proof valve and the casing body, reducing the difficulty of welding. Furthermore, the flatness of the surfaces of the connecting part and the first wall surface that are facing each other is limited, thereby ensuring a tight fit between the connecting part and the first wall surface and avoiding gaps between them. This prevents defects such as incomplete welding and weld holes during through-welding, thus improving the welding quality and increasing the welding strength.

[0022] This utility model also provides a battery that, by applying the aforementioned battery casing, not only reduces the difficulty of assembly and improves the efficiency of assembly, but also has higher structural strength and airtightness, thereby improving product quality. Attached Figure Description

[0023] Figure 1 This is a structural cross-sectional view of the first wall surface of the battery casing provided by this utility model;

[0024] Figure 2 This is an assembly diagram of the outer casing body and the explosion-proof valve in the battery casing provided by this utility model;

[0025] Figure 3 This is a schematic diagram of the front structure of the explosion-proof valve in the battery casing provided by this utility model;

[0026] Figure 4 This is a schematic diagram of the structure of the back of the explosion-proof valve in the battery casing provided by this utility model.

[0027] In the picture:

[0028] 1. Outer shell; 11. First wall surface;

[0029] 2. Explosion-proof valve; 21. Sealing part; 22. Connecting part; 23. First groove; 24. Second groove; 25. Weakening structure. Detailed Implementation

[0030] The present invention will now be described in further detail with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are merely illustrative of the present invention and not intended to limit it. Furthermore, it should be noted that, for ease of description, the accompanying drawings show only the parts relevant to the present invention, not the entire structure.

[0031] In the description of this utility model, unless otherwise explicitly specified and limited, the terms "connected," "linked," and "fixed" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral part; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium; they can refer to the internal communication of two components or the interaction between two components. Those skilled in the art can understand the specific meaning of the above terms in this utility model based on the specific circumstances.

[0032] In this invention, unless otherwise explicitly specified and limited, "above" or "below" the second feature can include direct contact between the first and second features, or contact between the first and second features through another feature between them. Furthermore, "above," "over," and "on top" of the second feature includes the first feature directly above or diagonally above the second feature, or simply indicates that the first feature is at a higher horizontal level than the second feature. "Below," "below," and "under" the second feature includes the first feature directly below or diagonally below the second feature, or simply indicates that the first feature is at a lower horizontal level than the second feature.

[0033] In the description of this embodiment, the terms "upper," "lower," "right," etc., refer to the orientation or positional relationship shown in the accompanying drawings. They are used only for ease of description and simplification of operation, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limitations on this utility model. In addition, the terms "first" and "second" are only used for distinction in description and have no special meaning.

[0034] When an explosion-proof valve is installed on the side wall of the housing, the installation area that the side wall of the housing can provide for the explosion-proof valve is limited, which results in a relatively narrow area for welding the explosion-proof valve to the side wall of the housing. This not only makes welding difficult, but also results in poor strength and airtightness after welding.

[0035] Therefore, in order to reduce the difficulty of welding and enhance the strength and airtightness after welding, this embodiment provides a battery casing.

[0036] like Figures 1 to 4 As shown, the battery casing includes a casing body 1 and an explosion-proof valve 2. The casing body 1 includes a first wall surface 11 with a mounting hole. The explosion-proof valve 2 includes a sealing part 21 and a connecting part 22. The sealing part 21 is inserted into the mounting hole. The connecting part 22 is located outside the casing body 1 and abuts against the outer side of the first wall surface 11. The connecting part 22 is connected to the casing body 1 by through welding. The flatness of the surface of the connecting part 22 facing the first wall surface 11 does not exceed 0.2 mm, and the flatness of the surface of the first wall surface 11 facing the connecting part 22 does not exceed 0.3 mm.

[0037] The battery casing includes an explosion-proof valve 2 consisting of a sealing part 21 and a connecting part 22. By inserting the sealing part 21 of the explosion-proof valve 2 into the mounting hole on the first wall surface 11 of the casing body 1, and using a through-welding method to connect the connecting part 22 to the outside of the first wall surface 11, not only is there an overlap between the connecting part 22 and the first wall surface 11 in space, improving space utilization, but also the use of through-welding eliminates the need to reserve an additional welding area. This ensures that the explosion-proof valve 2 has a sufficient opening area while also ensuring that there is a sufficient welding area between the explosion-proof valve 2 and the casing body 1, reducing the difficulty of welding. Furthermore, the flatness of the surfaces of the connecting part 22 and the first wall surface 11 that are facing each other is limited, thereby ensuring a tight fit between the connecting part 22 and the first wall surface 11 and avoiding gaps between them. This would prevent defects such as incomplete welding and weld holes during through-welding, thus improving the quality and strength of the welding.

[0038] In this embodiment, since the mounting holes on the first wall surface 11 of the outer casing 1 and the forming of the explosion-proof valve 2 are both manufactured using a stamping process, in order to meet the flatness requirements during welding, the explosion-proof valve 2 and the outer casing 1 need to be processed separately before assembly. After the flatness adjustment meets the set range, the explosion-proof valve 2 and the outer casing 1 are assembled, that is, the sealing part 21 of the explosion-proof valve 2 is inserted into the mounting hole of the outer casing 1. At this time, the connecting part 22 of the explosion-proof valve 2 will abut against the outside of the first wall surface 11 of the outer casing 1. Then, the overlapping area between the connecting part 22 and the first wall surface 11 is welded using a penetration welding device. The battery casing provided in this application can be applied to different types of batteries, such as blade batteries or prismatic batteries. In this embodiment, such as Figure 2 As shown, the battery casing is adapted to a blade battery, so the casing body 1 is a hollow shell structure with openings on both sides, and the first wall 11 is the wall with a smaller cross-sectional area on the casing body 1.

[0039] Optionally, such as Figure 1 As shown, the thickness of the connecting part 22 along the first direction is T1, which satisfies 0.3mm≤T1≤1mm. Since the connecting part 22 is connected to the first wall surface 11 by penetration welding, limiting the thickness T1 of the connecting part 22 along the first direction to satisfy 0.3mm≤T1≤1mm avoids both situations where the thickness of the connecting part 22 is too small, affecting the structural strength after welding, and where the thickness of the connecting part 22 is too large, increasing the difficulty of penetration during welding and reducing the welding quality.

[0040] The thickness T1 of the connecting part 22 along the first direction can be any value between 0.3mm and 1mm or a range between any two values, such as 0.3mm, 0.4mm, 0.5mm, 0.6mm, 0.7mm, 0.8mm, 0.9mm, 1mm, etc.

[0041] Optionally, such as Figure 1 As shown, the overlap width between the connecting part 22 and the first wall surface 11 along the second direction is L1, and satisfies 0.5mm≤L1≤1.5mm. By limiting the overlap width L1 between the connecting part 22 and the first wall surface 11 along the second direction to satisfy 0.5mm≤L1≤1.5mm, on the one hand, it avoids the overlap width between the connecting part 22 and the first wall surface 11 being too small, which would result in insufficient welding area for penetration welding and affect the welding quality; on the other hand, it avoids the overlap width between the connecting part 22 and the first wall surface 11 being too large, which would result in dimensional redundancy, material waste, and increased manufacturing costs.

[0042] The width L1 of the connection part 22 overlapping with the first wall surface 11 along the second direction can be any value between 0.5mm and 1.5mm or a range between any two values, such as 0.5mm, 0.6mm, 0.7mm, 0.8mm, 0.9mm, 1mm, 1.1mm, 1.2mm, 1.3mm, 1.4mm, 1.5mm, etc.

[0043] Optionally, such as Figure 1 , Figure 3 As shown, the explosion-proof valve 2 has a first groove 23 on the side opposite to the first wall surface 11. By creating the first groove 23 on the side of the explosion-proof valve 2 opposite to the first wall surface 11, the thickness of the explosion-proof valve 2 is reduced, and the structural strength at the location where the first groove 23 is created is lowered, so that in the event of thermal runaway, the gas can break through the area where the first groove 23 is created in the explosion-proof valve 2 and discharge the pressurized gas.

[0044] Furthermore, such as Figure 1 , Figure 3 As shown, the explosion-proof valve 2 also has a second groove 24 located within the first groove 23. By creating the second groove 24 within the first groove 23, the first groove 23 and the second groove 24 cooperate, further reducing the thickness of the explosion-proof valve 2 and lowering the structural strength at the location where the second groove 24 is created. This allows gas to break through the area where the second groove 24 is created in the event of thermal runaway, releasing pressurized gas. At the same time, compared to creating grooves of the same depth, using a larger first groove 23 and a smaller second groove 24 stacked together achieves the same depth while retaining more material for the explosion-proof valve 2, ensuring sufficient structural strength.

[0045] Furthermore, such as Figure 1 , Figure 3 As shown, the width of the mounting hole along the second direction is S, the width of the first groove 23 along the second direction is S1, and the width of the second groove 24 along the second direction is S2, satisfying 2mm≤(S-S1) / 2≤(S-S2) / 2. By limiting the width S1 of the first groove 23 and the width S2 of the second groove 24 along the second direction, both are made to satisfy 2mm≤(S-S1) / 2≤(S-S2) / 2, thus ensuring sufficient material thickness between the first groove 23 and the outer edge of the explosion-proof valve 2, thereby ensuring sufficient structural strength of the explosion-proof valve 2.

[0046] Optionally, such as Figure 1 , Figure 3 As shown, the explosion-proof valve 2 also has a weakening structure 25, which is located within the second groove 24. By providing the weakening structure 25 within the second groove 24, the thickness of the explosion-proof valve 2 is further reduced, decreasing the resistance to gas breaking through the explosion-proof valve 2. This ensures that in the event of thermal runaway, the high-pressure gas generated can break through the weakening structure 25, thereby opening the explosion-proof valve 2 and achieving the purpose of pressure relief protection.

[0047] Specifically, the weakening structure 25 is a groove extending along the first direction, and the thickness of the second groove 24 where the groove is formed is less than the thickness of the second groove 24 where the groove is not formed.

[0048] Optionally, such as Figure 1 As shown, the thickness of the first wall surface 11 along the first direction is T2, which satisfies 0.15mm≤T2≤2mm. By limiting the thickness T2 of the first wall surface 11 along the first direction to satisfy 0.15mm≤T2≤2mm, it avoids both excessive thickness of the first wall surface 11, which would result in dimensional redundancy and material waste, and insufficient thickness of the first wall surface 11, which would cause the first wall surface 11 to be welded through during penetration welding.

[0049] In this embodiment, a battery is also provided, comprising a cover plate, electrode assembly, and the aforementioned battery casing. The cover plate covers the opening of the battery casing and closes the battery casing, thereby forming a receiving cavity for accommodating the electrode assembly. By applying the aforementioned battery casing, this battery not only reduces assembly difficulty and improves assembly efficiency, but also has higher structural strength and airtightness, thus improving product quality.

[0050] Obviously, the above embodiments of this utility model are merely examples for clearly illustrating the present utility model, and are not intended to limit the implementation of the present utility model. Those skilled in the art can make various obvious changes, readjustments, and substitutions without departing from the protection scope of this utility model. It is neither necessary nor possible to exhaustively describe all embodiments here. Any modifications, equivalent substitutions, and improvements made within the spirit and principles of this utility model should be included within the protection scope of the claims of this utility model.

Claims

1. A battery casing, characterized in that, The battery casing includes: The outer casing body includes a first wall surface, on which mounting holes are provided; An explosion-proof valve, comprising a plugging part and a connecting part, wherein the plugging part is inserted into the mounting hole, the connecting part is located outside the outer shell and abuts against the outer side of the first wall surface, and the connecting part is connected to the outer shell by a through weld. The flatness of the surface of the connecting part facing the first wall surface does not exceed 0.2 mm, and the flatness of the surface of the first wall surface facing the connecting part does not exceed 0.3 mm.

2. The battery casing according to claim 1, characterized in that, The thickness of the connecting part along the first direction is T1, which satisfies 0.3mm≤T1≤1mm.

3. The battery casing according to claim 1, characterized in that, The width of the connection portion overlapping the first wall surface along the second direction is L1, and satisfies 0.5mm≤L1≤1.5mm.

4. The battery casing according to claim 1, characterized in that, The explosion-proof valve has a first groove on the side opposite to the first wall surface.

5. The battery casing according to claim 4, characterized in that, The explosion-proof valve also has a second groove located within the first groove.

6. The battery casing according to claim 5, characterized in that, The width of the mounting hole along the second direction is S, the width of the first groove along the second direction is S1, and the width of the second groove along the second direction is S2, and they satisfy 2mm≤(S-S1) / 2≤(S-S2) / 2.

7. The battery casing according to claim 6, characterized in that, The explosion-proof valve also has a weakening structure, which is located in the second groove.

8. The battery casing according to claim 7, characterized in that, The weakening structure is a groove extending along a first direction, and the thickness of the second groove where the groove is formed is less than the thickness of the second groove where the groove is not formed.

9. The battery casing according to claim 1, characterized in that, The thickness of the first wall surface along the first direction is T2, which satisfies 0.15mm≤T2≤2mm.

10. A battery, characterized in that, The battery includes a cover plate, an electrode assembly, and a battery casing as described in any one of claims 1-9, wherein the cover plate covers the opening of the battery casing and closes the battery casing to form a receiving cavity for accommodating the electrode assembly.

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