Battery shell, single battery and electric device

Abstract

The utility model relates to a battery shell, a single battery and an electric device, belongs to the technical field of batteries, and solves the problems that in the prior art, when a cover plate is welded to the shell, laser can enter from a gap to damage internal parts of the battery, and the welding reliability is influenced due to insufficient centering. The utility model provides a battery shell. The battery shell comprises a first wall, a second wall, a third wall and a fourth wall which are connected in sequence, the first wall, the second wall, the third wall and the fourth wall are provided with inner wall surfaces and outer wall surfaces; first protruding parts are continuously arranged on the inner wall faces of the first wall, the second wall, the third wall and the fourth wall in the circumferential direction. The first protruding part is an annular whole. A second protruding part is arranged on the upper surface of the first protruding part in the length direction, and the second protruding part is used for positioning a top cover of the battery; the second protruding part is provided with two inclined faces, and rough structures are arranged on the inclined faces. The laser welding device can prevent laser from entering the battery to damage parts and improve the welding reliability.

Description

Technical Field

[0001] The utility model relates to the technical field of batteries, in particular to a battery shell, a single battery and an electrical device. Background Art

[0002] Square secondary batteries are a common form of secondary batteries that can provide stable energy output and a long service life and are suitable for a variety of application scenarios.

[0003] Most existing square batteries are composed of a square outer shell with an opening and a battery cover to form a closed accommodating cavity, and the electrode assembly is arranged inside the accommodating cavity; the shell and the battery top cover are usually welded.

[0004] On the one hand, due to the gap between the cover plate and the side wall of the battery shell, when the cover plate is welded to the shell, the laser will pass through the fitting gap between the battery shell and the cover plate and enter the interior of the battery shell, thereby damaging the battery cells inside the battery shell.

[0005] On the other hand, due to the insufficient centering and stability of the top cover at the opening of the battery shell, it is easy to deviate during welding, affecting the welding quality. Utility Model Content

[0006] In view of the above analysis, the embodiments of the present invention aim to provide a battery housing, a single cell and an electrical device to solve the problems in the prior art where the laser may penetrate through the gap when the cover plate is welded to the housing, damaging the internal components of the battery, and insufficient centering may affect the welding quality.

[0007] The purpose of this utility model is mainly achieved through the following technical solutions:

[0008] A first aspect of the present invention provides a battery housing, comprising a first wall, a second wall, a third wall, and a fourth wall connected in sequence; the first wall, the second wall, the third wall, and the fourth wall have an inner wall surface and an outer wall surface;

[0009] An opening is formed on the upper portions of the first wall, the second wall, the third wall, and the fourth wall, and the opening is used to mount the top cover; the upper surface of the top cover is flush with the upper edge of the battery housing;

[0010] A first protrusion is circumferentially provided on the inner wall surfaces of the first wall, the second wall, the third wall and the fourth wall; the first protrusion is formed into an annular whole;

[0011] Furthermore, a second protrusion is provided on the upper surface of the first protrusion along the length direction, and the second protrusion is used to position the top cover of the battery; the second protrusion is arranged in an arc shape, and the cross-section of the second protrusion is triangular; both sides of the second protrusion have inclined surfaces, and a rough structure is provided on the inclined surfaces.

[0012] Furthermore, the cross section of the first protrusion is triangular.

[0013] Furthermore, the first protrusion includes a right-angled triangular prism structure arranged on the inner surfaces of at least two walls of the first wall, the second wall, the third wall and the fourth wall, the first side surface of the right-angled triangular prism structure is in contact with the inner surface of the wall, and the second side surface of the right-angled triangular prism structure serves as the upper surface of the first protrusion.

[0014] Furthermore, the cross section of the right-angled triangular prism structure is a right triangle, and the right triangle includes a first right-angled side and a second right-angled side, the first right-angled side is located on the first side surface, and the second right-angled side is located on the second side surface.

[0015] The length of the second right-angled side of the first protrusion is 30% to 100% of the thickness of the first wall of the battery housing, and the length of the first right-angled side of the first protrusion is 1 mm to 1.5 mm.

[0016] Furthermore, the second protrusion is provided on the first protrusion of the first wall and the third wall.

[0017] Furthermore, the second protrusions are arranged continuously or at intervals.

[0018] Furthermore, it includes a bottom cover, which is arranged at the lower part of the first wall, the second wall, the third wall and the fourth wall, and the bottom cover and the first wall, the second wall, the third wall and the fourth wall form a receiving cavity.

[0019] A second aspect of the present invention provides a single cell battery comprising a top cover, an electrode assembly and the battery housing;

[0020] The length of the top cover is 0.1-0.5 mm smaller than the length of the second wall; the width of the top cover is 0.1-0.5 mm smaller than the length of the first wall; the side walls of the top cover are welded to the inner wall surfaces of the first wall, the second wall, the third wall, and the fourth wall; the top cover has an arc-shaped groove matching the second protrusion;

[0021] The electrode assembly is disposed in the accommodating cavity of the battery housing.

[0022] The third aspect of the present invention provides an electrical device comprising the aforementioned single cell battery.

[0023] Compared with the prior art, the present invention can achieve at least one of the following beneficial effects:

[0024] (1) Compared with the prior art, the cross-section of the first protrusion of the present invention is a right triangle to provide a stable support for the top cover. The first protrusion is continuous in an annular structure along the inner wall of the battery case to prevent the laser from penetrating through the gap between the battery case and the top cover during welding and damaging the battery cells inside the battery case.

[0025] (2) The utility model provides a second protrusion with a triangular cross-section on the upper surface of the first protrusion. The second protrusion is arranged in an arc shape to match the groove of the top cover, thereby fixing the top cover stably and centered, and improving the welding quality. The utility model provides a rough structure such as a small protrusion on the inclined surface of the second protrusion that matches the groove of the top cover to prevent the top cover from sliding, further improving the stability of the top cover.

[0026] (3) In the present invention, the thickness of the wall is not changed, so that the external shape and strength of the battery shell remain unchanged. Only the first protrusion is provided on the inner wall surface to support the top cover, which can absorb the stress during welding, improve the reliability of welding, and further enhance the stability of the battery.

[0027] (4) The utility model sets the length of the second right-angled side of the first protrusion to 30% to 100% of the thickness of the first wall, and the length of the first right-angled side of the first protrusion is 1 mm to 1.5 mm, so as to avoid affecting the battery core shell insertion process when the width or thickness of the first protrusion is too large; if the width or thickness of the first protrusion is too small, the support effect on the top cover cannot be achieved.

[0028] In the present invention, the above-mentioned technical solutions can be combined with each other to achieve more preferred combinations. Other features and advantages of the present invention will be described in the following content, and some advantages will become apparent from the description or be understood through practice of the present invention. The objectives and other advantages of the present invention can be realized and obtained through the contents particularly pointed out in the text and drawings. BRIEF DESCRIPTION OF THE DRAWINGS

[0029] The accompanying drawings are only used for the purpose of illustrating specific embodiments and are not to be considered as limiting the present invention. Throughout the accompanying drawings, the same reference symbols denote the same components.

[0030] Figure 1 is a structural schematic diagram of a battery housing according to a specific embodiment;

[0031] Figure 2 A schematic structural diagram of a first protrusion and a second protrusion arranged continuously;

[0032] Figure 3 A schematic structural diagram of a first protrusion and a second protrusion spaced apart;

[0033] Figure 4 A schematic diagram of a battery structure according to a specific embodiment;

[0034] Figure 5 for Figure 4 A cross-sectional schematic diagram of the direction A;

[0035] Figure 6 It is a schematic diagram of the enlarged structure of the connection between the first protrusion, the second protrusion and the top cover in a specific embodiment.

[0036] Reference numerals:

[0037] 1-battery housing, 101-first wall, 102-second wall, 103-third wall, 104-fourth wall, 105-first protrusion, 106-second protrusion, 2-top cover, 201-groove. DETAILED DESCRIPTION

[0038] The preferred embodiments of the present invention will be described in detail below in conjunction with the accompanying drawings, wherein the accompanying drawings constitute a part of the present invention and are used together with the embodiments of the present invention to illustrate the principles of the present invention, and are not used to limit the scope of the present invention.

[0039] A specific embodiment of the present invention is as follows Figure 1 As shown, a battery housing 1 is disclosed. The battery housing 1 is square and is used for a secondary battery. The battery housing 1 is made of metal. In this embodiment, the battery housing 1 is an aluminum shell.

[0040] The battery case 1 contains an electrode assembly. The battery case 1 includes a first wall 101, a second wall 102, a third wall 103, a fourth wall 104, and a bottom cover. The first wall 101, the second wall 102, the third wall 103, and the fourth wall 104 are connected in sequence, the upper part is surrounded by an opening, and the lower part is provided with a bottom cover. The first wall 101, the second wall 102, the third wall 103, and the fourth wall 104 are all perpendicular to the bottom cover. The first wall 101 and the third wall 103 are arranged opposite to each other, and the second wall 102 and the fourth wall 104 are arranged opposite to each other, and the first wall 101 and the second wall 102 are perpendicular to each other. The length of the first wall 101 is less than the length of the second wall 102. The first wall 101, the second wall 102, the third wall 103, and the fourth wall 104 have an inner wall surface and an outer wall surface.

[0041] Furthermore, when the top cover 2 is welded to the battery housing 1 , the laser will penetrate through the fitting gap between the battery housing 1 and the top cover 2 and into the interior of the battery housing 1 , thereby damaging the battery core inside the battery housing 1 .

[0042] In order to overcome the above problems, Figure 2 and Figure 3 As shown, first protrusions 105 are provided on the inner surfaces of the first wall 101, the second wall 102, the third wall 103, and the fourth wall 104. The first protrusions 105 are circumferentially distributed along the inner surfaces. The first protrusions 105 are continuously distributed along the inner surfaces of the first wall 101, the second wall 102, the third wall 103, and the fourth wall 104 to form an annular entity with a uniform width. The upper surface of the first protrusions 105 is used to support the top cover 2, and the first protrusions 105 can provide support and support for the top cover 2.

[0043] Furthermore, to provide stable support for the top cover 2, the first protrusion 105 has a triangular cross-section. Because the first protrusion 105 is located below the top cover 2 and on the inner wall of the battery housing, compared to the prior art solution of thinning the short wall of the battery housing to form a step, this embodiment achieves a deeper molten pool when welding the top cover 2 to the battery housing 1, dispersing welding stress, preventing weld cracks, and ensuring more reliable welding.

[0044] Considering that when the top cover 2 is welded to the battery case 1, there is a gap for welding around the side wall of the top cover 2 and the inner wall of the battery case 1. In order to further ensure that the top cover 2 is welded firmly and the top cover 2 is centered in the opening of the battery case 1 to ensure the quality and accuracy of the welding, a second protrusion 106 is provided on the upper surface of the first protrusion 105 to match the groove 201 of the top cover 2. The second protrusion 106 is provided on the first protrusion 105 of the first wall 101 and the third wall 103.

[0045] Since a triangle shape is easier to insert and more secure, the cross section of the second protrusion 106 is triangular. The second protrusion 106 has inclined surfaces on both sides. Furthermore, the second protrusion 106 is arranged in an arc shape on the first protrusion 105, and the arrangement can be continuous or spaced to better position the top cover 2.

[0046] Furthermore, in order to improve the stability between the second protrusion 106 and the groove 201 of the top cover 2, a rough structure such as a small protrusion is provided on the triangular inclined surface of the second protrusion 106 to reduce the shaking of the top cover 2 during welding.

[0047] In this embodiment, the first protrusion 105 comprises a right-angled triangular prism structure disposed on the inner surfaces of at least two of the first wall 101, the second wall 102, the third wall 103, and the fourth wall 104. The first side surface of the triangular prism structure contacts the inner surface of the wall, and the second side surface serves as the upper surface of the first protrusion 105. The cross-section of the triangular prism structure is a right triangle, and the right triangle includes a first right-angled side and a second right-angled side. The first right-angled side is located on the first side, and the second right-angled side is located on the second side.

[0048] When the width or thickness of the first protrusion 105 is too large, it will affect the process of inserting the battery core into the shell; when the width or thickness of the first protrusion 105 is too small, it cannot achieve the supporting effect on the top cover 2. The length of the second right-angled side of the first protrusion 105 is set to 30% to 100% of the thickness of the first wall 101, and the length of the first right-angled side of the first protrusion 105 is 1 mm to 1.5 mm.

[0049] Compared with the prior art, the cross-section of the first protrusion 105 perpendicular to the length direction is a triangle in the shape of a supporting rib in this embodiment to provide a stable support for the top cover 2. The first protrusion 105 is a continuous annular structure on the circumference of the inner wall surface of the battery shell 1 to prevent the laser from passing through the matching gap between the battery shell 1 and the top cover 2 during welding and penetrating into the interior of the battery shell 1, thereby damaging the battery core inside the battery shell 1. In this embodiment, a second protrusion 106 with a triangular cross-section is provided on the upper surface of the first protrusion 105, and the second protrusion 106 is arranged in an arc shape to match the groove 201 of the top cover 2, so that the top cover 2 is fixed, stable and centered, thereby improving the welding quality. In this embodiment, a rough structure such as a small protrusion is provided on the inclined surface of the second protrusion 106 that matches the groove 201 of the top cover 2 to prevent the top cover 2 from sliding.

[0050] In this embodiment, the thickness of the wall is not changed, so that the external shape and strength of the battery housing 1 remain unchanged. Only the first protrusion 105 is provided on the inner wall to support the top cover 2. This can absorb the stress during welding, improve the reliability of welding, and further enhance the stability of the battery.

[0051] This embodiment further provides a single battery, comprising the battery case 1 , the top cover 2 and the electrode assembly accommodated in the battery case 1 in the above embodiment.

[0052] like Figure 4 As shown, the top cover 2 is positioned within the opening of the battery casing 1. Accordingly, the length and width of the top cover 2 are smaller than the opening of the battery casing 1, and the top surface of the top cover 2 is flush with the upper edge of the battery casing 1. Specifically, the length and width of the top cover 2 are 0.1-0.5 mm smaller than the length and width of the inner wall of the battery casing 1, respectively. The side walls of the top cover 2 are welded to the inner surfaces of the first wall 101, the second wall 102, the third wall 103, and the fourth wall 104.

[0053] like Figure 5 and Figure 6 As shown, correspondingly, a groove 201 is provided at the lower portion of the top cover 2 to match the second protrusion 106 , and the second protrusion 106 can be inserted into the groove 201 to limit the top cover 2 .

[0054] The top cover 2 is equipped with positive and negative electrode posts, an explosion-proof valve, and a liquid injection port. The electrode assembly is formed by winding or stacking the positive electrode sheet, separator, and negative electrode sheet. The upper portion of the electrode assembly is designed with positive and negative electrode tabs. The positive tab is connected to the positive terminal on the top cover 2, and the negative tab is connected to the negative terminal on the top cover 2 via an adapter.

[0055] This embodiment further provides an electrical device, comprising the single battery described in the above embodiment.

[0056] Compared with the prior art, the advantages of the single battery and the electrical device of the embodiment of the present invention are the same as the advantages of the structure of the battery housing 1 described above, which will not be repeated here.

[0057] The above is only a preferred specific implementation method of the present invention, but the protection scope of the present invention is not limited to this. Any changes or replacements that can be easily thought of by any technician familiar with this technical field within the technical scope disclosed in the present invention should be covered by the protection scope of the present invention.

Claims

1. A battery housing, characterized in that: The invention comprises a first wall (101), a second wall (102), a third wall (103) and a fourth wall (104) connected in sequence; the first wall (101), the second wall (102), the third wall (103) and the fourth wall (104) have an inner wall surface and an outer wall surface; The upper portions of the first wall (101), the second wall (102), the third wall (103) and the fourth wall (104) are surrounded by openings, and the openings are used to arrange a top cover (2); the upper surface of the top cover (2) is flush with the upper edge of the battery housing (1); A first protrusion (105) is circumferentially provided on the inner wall surfaces of the first wall (101), the second wall (102), the third wall (103) and the fourth wall (104); the first protrusion (105) is formed into an annular whole.

2. The battery case according to claim 1, wherein: A second protrusion (106) is provided on the upper surface of the first protrusion (105), and the second protrusion (106) is used to position the top cover (2) of the battery; the second protrusion (106) is arranged in an arc shape, and the cross section of the second protrusion (106) is triangular; both sides of the second protrusion (106) have inclined surfaces, and the inclined surfaces are provided with a rough structure.

3. The battery case according to claim 1, wherein: The cross section of the first protrusion (105) is triangular.

4. The battery case according to claim 3, characterized in that The first protrusion (105) includes a right-angled triangular prism structure arranged on the inner surfaces of at least two walls of the first wall (101), the second wall (102), the third wall (103) and the fourth wall (104), the first side surface of the right-angled triangular prism structure is in contact with the inner surface of the wall, and the second side surface of the right-angled triangular prism structure serves as the upper surface of the first protrusion (105).

5. The battery case according to claim 4, characterized in that The cross section of the right-angled triangular prism structure is a right triangle, and the right triangle includes a first right-angled side and a second right-angled side, the first right-angled side is located on the first side surface, and the second right-angled side is located on the second side surface; the length of the second right-angled side is 30% to 100% of the thickness of the first wall (101), and the length of the first right-angled side is 1 mm to 1.5 mm.

6. The battery case according to claim 2, characterized in that The second protrusion (106) is provided on the first protrusion (105) of the first wall (101) and the third wall (103).

7. The battery case according to claim 2, wherein: The second protrusions (106) are arranged continuously or at intervals.

8. The battery case according to claim 1, wherein: The invention also includes a bottom cover, which is arranged at the lower part of the first wall (101), the second wall (102), the third wall (103) and the fourth wall (104), and the bottom cover forms a receiving cavity with the first wall (101), the second wall (102), the third wall (103) and the fourth wall (104).

9. A single cell battery, characterized in that: Comprising the top cover (2), an electrode assembly and the battery casing (1) according to any one of claims 1 to 8; The length of the top cover (2) is 0.1-0.5 mm smaller than the length of the second wall (102); the width of the top cover (2) is 0.1-0.5 mm smaller than the length of the first wall (101); the side walls of the top cover (2) are welded to the inner wall surfaces of the first wall (101), the second wall (102), the third wall (103) and the fourth wall (104); the top cover (2) has an arc-shaped groove (201) that matches the second protrusion (106); The electrode assembly is arranged in the accommodating cavity of the battery housing (1).

10. An electrical device, characterized in that: The invention comprises the single cell battery according to claim 9.

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