Square battery shell structure

Abstract

The utility model discloses a square battery shell structure which comprises a shell, a core bag is arranged in the shell, and a core bag insulating sheet is sleeved on the core bag; the positive top cover and the negative top cover are respectively arranged at the positive end and the negative end of the square battery; a thickened boss part is formed at a position where the shell is matched with the corresponding top cover, and a step part is formed at a position where the top cover is matched with the thickened boss part; the width of the step part is larger than the thickness of the thickened boss part, and the top cover is in clearance fit with the shell. According to the utility model, the shell structure adopts the design of the boss structure with the thickened opening part, so that the shell structure has larger metal welding penetration after being matched and welded with the top cover, and the welding seam strength of the shell and the top cover can be improved, thereby ensuring that the single battery has very strong pressure resistance.

Description

Technical Field

[0001] The utility model relates to the technical field of lithium-ion batteries, in particular to a square battery case structure. Background Art

[0002] In recent years, lithium-ion batteries have been widely used in the fields of power and storage. The industry's requirements for the energy density of lithium batteries have been gradually increasing, and lithium batteries have gradually developed towards lightweight. Among them, the thinning of the battery case can effectively reduce the weight of the battery cell, thereby increasing the weight density and reducing the cost.

[0003] However, the thinning of the battery case will lead to a reduction in the structural strength of the battery itself and an increase in the failure risk of the battery case, thereby reducing the safety of the battery cell. Therefore, in the context of the thinning of the battery case, it is particularly important to improve the structural strength of the case.

[0004] Therefore, based on the above technical problems, those skilled in the art urgently need to develop a square battery case structure. Summary of the Utility Model

[0005] The purpose of the utility model is to provide a square battery case structure. The case structure adopts a boss structure design with a thickened mouth part. After being welded in cooperation with the top cover, it has a large metal welding penetration depth, can improve the weld strength of the case and the top cover, and thus ensure that the single battery has a strong pressure resistance.

[0006] In order to achieve the above purpose, the utility model provides the following technical solutions:

[0007] A square battery case structure of the utility model, the case structure includes:

[0008] A case, a battery cell is installed inside the case, and a cell insulating sheet is sleeved on the battery cell; and

[0009] A positive top cover and a negative top cover respectively installed at the positive and negative poles of the square battery;

[0010] A thickened boss part is formed at the position where the case is in cooperation with the corresponding top cover, and a stepped part is formed by the cooperation of the top cover and the thickened boss part;

[0011] The width of the stepped part is greater than the thickness of the thickened boss part, and the top cover is in clearance fit with the case.

[0012] Further, the top cover includes:

[0013] A top cover embedding part; and

[0014] The stepped part formed at the edge of the top cover embedding part and in cooperation with the thickened boss part;

[0015] The top cover embedding part is in clearance fit with the shell.

[0016] Furthermore, the shell includes:

[0017] A shell body; and

[0018] The thickened boss part formed at one end of the shell body cooperating with the top cover and protruding towards the outer side surface of the shell body;

[0019] The thickness of the shell body is h;

[0020] The thickness of the thickened boss part is h + n;

[0021] The width of the stepped part is h + n + l, where l is from 0.05 mm to 0.5 mm.

[0022] Furthermore, when the top cover is installed at the corresponding end of the shell, the outer end surface of the stepped part is flush with the outer end surface of the thickened boss part.

[0023] Furthermore, the shell includes:

[0024] A shell body; and

[0025] The thickened boss part formed at one end of the shell body cooperating with the top cover and protruding towards the inner side surface of the shell body;

[0026] The thickness of the shell body is h;

[0027] The thickness of the thickened boss part is h + n;

[0028] The width of the stepped part is h + n + l, where l is from 0.05 mm to 0.5 mm.

[0029] Furthermore, the outer end surface of the stepped part is flush with the outer end surface of the thickened boss part.

[0030] Furthermore, the transition position between the thickened boss part and the shell body is transitioned through an inclined surface.

[0031] In the above technical solution, a square battery shell structure provided by the present utility model has the following beneficial effects:

[0032] The shell structure of the present utility model adopts a boss structure design with a thickened mouth part. After being welded in cooperation with the top cover, it has a large metal welding penetration depth, can improve the weld strength of the shell and the top cover, and thus ensure that the single battery has a strong pressure resistance ability.

[0033] The housing structure of the present utility model improves the weld strength between the housing and the top cover, while reducing the risk of the housing catching fire and exploding during thermal runaway of the battery; it improves the long-term reliability of the battery housing and reduces the fatigue failure of the weld metal.

[0034] The housing structure of the present utility model can reduce the weight of the battery on the basis of maintaining the original structural strength performance of the battery, thereby improving the energy density. Brief Description of the Drawings

[0035] In order to more clearly illustrate the technical solutions in the embodiments of the present application or the prior art, the following will briefly introduce the drawings required for use in the embodiments. Obviously, the drawings described below are only some embodiments recorded in the present utility model. For those of ordinary skill in the art, other drawings can also be obtained based on these drawings.

[0036] Figure 1 Structural schematic diagram of a square battery housing structure disclosed in an embodiment of the present application;

[0037] Figure 2 Front view of the first implementation manner of a square battery housing structure disclosed in an embodiment of the present application;

[0038] Figure 3 For Figure 2 Cross-sectional view taken along the A-A direction in

[0039] Figure 4 Enlarged view of the connection structure between the top cover and the housing of the first implementation manner of a square battery housing structure disclosed in an embodiment of the present application;

[0040] Figure 5 Enlarged view of a part of the housing of the first implementation manner of a square battery housing structure disclosed in an embodiment of the present application;

[0041] Figure 6 Front view of the second implementation manner of a square battery housing structure disclosed in an embodiment of the present application;

[0042] Figure 7 For Figure 6 Cross-sectional view taken along the E-E direction in

[0043] Figure 8 Enlarged view of the connection structure between the top cover and the housing of the second implementation manner of a square battery housing structure disclosed in an embodiment of the present application;

[0044] Figure 9 Enlarged view of a part of the housing of the second implementation manner of a square battery housing structure disclosed in an embodiment of the present application.

[0045] Explanation of the Reference Numerals:

[0046] 1. Housing; 2. Top cover;

[0047] 101. Core package; 102. Core package insulating sheet; 103. Housing body; 104. Thickened boss part; 105. Gap; 106. Inclined surface;

[0048] 201. Positive top cover; 202. Negative top cover; 203. Top cover embedding part; 204. Step part. Detailed implementation manner

[0049] In order to enable those skilled in the art to better understand the technical solution of the present utility model, the present utility model will be further described in detail below with reference to the accompanying drawings.

[0050] See Figure 1 as shown;

[0051] This embodiment discloses a square battery housing structure, which includes:

[0052] Housing 1, inside which a core package 101 is installed, and the core package 101 is sleeved with a core package insulating sheet 102; and

[0053] A positive top cover 201 and a negative top cover 202 respectively installed at the positive and negative ends of the square battery;

[0054] A thickened boss part 104 is formed at the position where the housing 1 cooperates with the corresponding top cover 2, and a step part 204 is formed by the cooperation of the top cover 2 and the thickened boss part 104;

[0055] The width of the step part 204 is greater than the thickness of the thickened boss part 104, and the top cover 2 is in clearance fit with the housing 1.

[0056] Specifically, this embodiment discloses a novel housing structure of a square battery. The structure includes a housing 1, inside which a core package 101 is installed. At the same time, according to the positive and negative poles of the square battery, a positive top cover 201 and a negative top cover 202 are respectively installed at both ends; in order to ensure the weld strength and pressure resistance of the housing 1 and the top cover 2 on the basis of thinning the housing 1, a thickened boss part 104 is formed at one end of the housing 1 where it cooperates with the top cover 2, and a step part 204 is correspondingly provided on the top cover 2. The step part 204 overlaps on the thickened boss part 104, and through the thickening design, it has a large metal welding penetration depth after being welded with the top cover 2, improving the weld strength, ensuring that the battery has strong pressure resistance, increasing the weld failure threshold of the battery in thermal runaway, and reducing the probability of the battery catching fire and exploding.

[0057] Preferably, the positive top cover 201 and the negative top cover 202 in this embodiment have the same structure. Therefore, they are combined together for further limitation. The top cover 2 in this embodiment includes:

[0058] The top cover embedding part 203; and

[0059] A step part 204 formed at the edge of the top cover embedding part 203 and cooperating with the thickening boss part 104;

[0060] The top cover embedding part 203 is in clearance fit with the housing 1.

[0061] Embodiment 1, as shown in the figure, this Embodiment 1 defines the first structure of the housing structure, that is, the structure in which the thickening boss part 104 of the housing 1 protrudes outward from the outer side of the housing body 103. Specifically: The housing 1 of this Embodiment 1 includes:

[0062] The housing body 103; and

[0063] A thickening boss part 104 formed at one end of the housing body 103 cooperating with the top cover 2 and protruding toward the outer side surface of the housing body 103;

[0064] The thickness of the housing body 103 is h;

[0065] The thickness of the thickening boss part 104 is h + n;

[0066] The width of the step part 204 is h + n + l, and l is from 0.05 mm to 0.5 mm.

[0067] Wherein, when the top cover 2 of this Embodiment 1 is installed at the corresponding end of the housing 1, the outer end surface of the step part 204 is flush with the outer end surface of the thickening boss part 104.

[0068] This Embodiment further defines the first structure of the housing 1. The housing 1 includes a housing body 101 and a thickening boss part 104 formed at the end of the housing body 103. Among them, the thickening boss part 104 of this Embodiment 1 is a structure protruding outward from the outer side of the housing body 103. The specific thickness design is that the thickness h of the housing body 103 < the thickness h + n of the thickening boss part 104 < the thickness h + n + l of the step part 204; In order to achieve the clearance fit between the top cover embedding part 203 and the thickening boss part 104, l of this Embodiment is from 0.05 mm to 0.5 mm, and the clearance 105 is reserved for easy assembly.

[0069] Embodiment 2, as shown in the figure, this Embodiment 2 defines the second structure of the housing structure, that is, the structure in which the thickening boss part 104 of the housing 1 protrudes inward from the inner side of the housing body 103. Specifically: The housing 1 of this Embodiment 2 includes:

[0070] The housing body 103; and

[0071] A thickening boss part 104 formed at one end of the housing body 103 cooperating with the top cover 2 and protruding toward the inner side surface of the housing body 103;

[0072] The thickness of the housing body 103 is h;

[0073] The thickness of the thickened boss portion 104 is h + n;

[0074] The width of the stepped portion 204 is h + n + l, where l ranges from 0.05 mm to 0.5 mm.

[0075] Among them, the outer end surface of the stepped portion 204 in the second embodiment is flush with the outer end surface of the thickened boss portion 104.

[0076] The main difference between the housing 1 in the second embodiment and the first embodiment is that the thickened boss portion 104 protrudes toward the inner side of the housing body 103 in the second embodiment, and the specific thickness requirements are similar to those in the first embodiment, which will not be elaborated here. At the same time, a gap 105l of 0.05 mm to 0.5 mm is reserved for convenient assembly.

[0077] In the above embodiment, the transition position between the thickened boss portion 104 and the housing body 103 is transitioned through an inclined surface 106.

[0078] The housing in this embodiment is made by metal processing techniques such as die stretching, stamping, bending, and welding.

[0079] In the above technical solution, a square battery housing structure provided by the present utility model has the following beneficial effects:

[0080] The housing structure of the present utility model adopts a boss structure design with a thickened mouth portion. After being welded with the top cover, it has a large metal welding penetration depth, which can improve the weld strength of the housing 1 and the top cover 2, thereby ensuring that the single battery has a strong pressure resistance.

[0081] While improving the weld strength of the housing 1 and the top cover 2, the housing structure of the present utility model reduces the risk of the housing 1 catching fire and exploding during thermal runaway of the battery; improves the long-term reliability of the battery housing and reduces weld metal fatigue failure.

[0082] The housing structure of the present utility model can reduce the weight of the battery on the basis of maintaining the original structural strength performance of the battery, thereby improving the energy density.

[0083] Only some exemplary embodiments of the present utility model have been described above by way of illustration. Undoubtedly, for those of ordinary skill in the art, without departing from the spirit and scope of the present utility model, the described embodiments can be modified in various different ways. Therefore, the above drawings and descriptions are illustrative in nature and should not be construed as limiting the protection scope of the claims of the present utility model.

Claims

1. A square battery housing structure, characterized in that, The housing structure includes: A housing (1) with a core package (101) installed inside, and the core package (101) is sleeved with a core package insulating sheet (102); and A positive top cover (201) and a negative top cover (202) respectively installed at the positive and negative extreme ends of the square battery; At the position where the housing (1) cooperates with the corresponding top cover (2), a thickened boss portion (104) is formed, and a stepped portion (204) is formed by the cooperation of the top cover (2) and the thickened boss portion (104); The width of the stepped portion (204) is greater than the thickness of the thickened boss portion (104), and the top cover (2) is in clearance fit with the housing (1); The top cover (2) includes: A top cover insertion portion (203); and The stepped portion (204) formed at the edge of the top cover insertion portion (203) and cooperating with the thickened boss portion (104); The top cover insertion portion (203) is in clearance fit with the housing (1).

2. The square battery housing structure according to claim 1, characterized in that, The housing (1) includes: A housing body (103); and The thickened boss portion (104) formed at one end of the housing body (103) that cooperates with the top cover (2) and protruding towards the outer side surface of the housing body (103).

3. The square battery housing structure according to claim 2, characterized in that, When the top cover (2) is installed at the corresponding end of the housing (1), the outer end surface of the stepped portion (204) is flush with the outer end surface of the thickened boss portion (104).

4. A square battery case structure according to claim 1, characterized in that, The housing (1) includes: A housing body (103); and The thickened boss portion (104) formed at one end of the housing body (103) that cooperates with the top cover (2) and protruding towards the inner side surface of the housing body (103).

5. The square battery case structure according to claim 4, characterized in that, The outer end surface of the stepped portion (204) is flush with the outer end surface of the thickened boss portion (104).

6. A square battery case structure according to claim 2 or 4, characterized in that, The transition position between the thickened boss portion (104) and the housing body (103) is transitioned through an inclined surface (106).

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