Unequal-wall asymmetric ultrathin high-strength battery shell, secondary battery and electric equipment

Abstract

The utility model discloses an unequal-wall asymmetric ultrathin high-strength battery shell, a secondary battery and electric equipment, the battery shell comprises a thick side surface and three thin side surfaces, and the thick side surface and the three thin side surfaces are enclosed to form a rectangular cylindrical structure with openings at two ends; an anti-explosion valve is arranged on the thick side face, and the wall thickness of the thick side face is larger than that of the three thin side faces. According to the utility model, the wall thicknesses of the four side surfaces of the battery shell are not consistent any more, and the three thin side surfaces without the anti-explosion valves can be thinned, so that the internal volume of the battery shell can be increased under the condition that the external size of the battery shell is not changed, and more battery materials can be loaded to increase the capacity of the battery; the material cost of the battery shell can be reduced; the structure is simple and practicability is high.

Description

Technical Field

[0001] The utility model belongs to the field of secondary battery shells, and particularly relates to an unequal-wall asymmetric ultra-thin high-strength battery shell, a secondary battery and electrical equipment. Background Art

[0002] See also Figure 1 In the prior art, the wall thicknesses of the four side surfaces 910 of the battery housing are generally equal. The manufacturing method thereof is generally to first stamp out a side component in an unfolded state, then bend the side component into a rectangular cylinder and then weld it to form four side surfaces 910 , and form a weld 920 on one of the side surfaces 910 .

[0003] In the past, secondary batteries (such as blade batteries) had explosion-proof valves generally made on the top cover, which would not affect the wall thickness of the four sides; however, with the development of secondary battery technology and the continuous expansion of its application scope, the method of making explosion-proof valves on the sides of secondary battery shells rather than on the top cover has been widely adopted. Since the wall thickness of the battery shell cannot meet the requirements for making explosion-proof valves when it is too thin, this limits the wall thickness of the battery shell, resulting in the battery shell being unable to be made too thin. Utility Model Content

[0004] In view of the above-mentioned deficiencies in the prior art, the technical problem to be solved by the present invention is to provide an unequal-wall asymmetric ultra-thin high-strength battery casing, a secondary battery and an electrical device.

[0005] In order to solve the above technical problems, the utility model provides the following technical solutions:

[0006] A non-symmetrical ultra-thin high-strength battery shell with unequal walls comprises a thick side surface and three thin side surfaces, wherein the thick side surface and the three thin side surfaces together form a rectangular cylindrical structure with openings at both ends; an explosion-proof valve is arranged on the thick side surface, and the wall thickness of the thick side surface is greater than the wall thickness of the three thin side surfaces.

[0007] Furthermore, the battery housing is an integrally formed seamless structure.

[0008] Furthermore, the battery housing is formed by extrusion of an aluminum alloy material, or by extrusion of an aluminum alloy material into a rectangular cylindrical structure and then by cold drawing.

[0009] Furthermore, the battery housing is formed by melting and casting using stainless steel or aluminum alloy.

[0010] Furthermore, the thick side is the first side, and the three thin sides are the second side, the third side and the fourth side respectively; the widths of the first side and the third side are equal, the widths of the second side and the fourth side are equal, and the width of the first side is smaller than the width of the second side; the wall thicknesses of the second side, the third side and the fourth side are all equal.

[0011] Furthermore, the battery housing is made of aluminum alloy, the wall thickness of the thick side is 0.8 mm to 1.2 mm, and the wall thickness of the thin side is 0.3 mm to 0.7 mm.

[0012] Furthermore, the wall thickness of the thick side surface is 0.8 mm, and the wall thickness of the thin side surface is 0.3 mm.

[0013] Furthermore, an explosion-proof hole is provided on the first side surface, the explosion-proof valve is an explosion-proof plate that is welded to close the explosion-proof hole, a reinforcing boss is provided on the outer edge of the explosion-proof plate, and a first explosion-proof notch is formed on the explosion-proof plate.

[0014] A secondary battery comprises an asymmetric ultra-thin high-strength battery shell with unequal walls.

[0015] An electric device includes a secondary battery.

[0016] In the utility model, the wall thickness of the four sides of the battery housing is no longer consistent, and the three thin sides without explosion-proof valves can be thinned, so that the internal volume of the battery housing can be increased while the external dimensions remain unchanged, so that more battery materials can be loaded to increase the battery capacity and reduce the material cost of the battery housing. Although the increased capacity and reduced material cost of each battery are limited, for products such as new energy vehicles that require a large number of batteries, the increased battery capacity and reduced material cost after accumulation are still very obvious. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] The drawings described herein are used to provide a further understanding of the present application and constitute a part of the present application. The illustrative embodiments of the present application and their descriptions are used to explain the present application and do not constitute an improper limitation on the present application. In the drawings:

[0018] Figure 1 It is a top view of a battery casing in the prior art.

[0019] Figure 2 It is a structural schematic diagram of an embodiment of an unequal-wall asymmetric ultra-thin high-strength battery casing of the utility model.

[0020] Figure 3 This is a schematic diagram of the structure when an explosion-proof valve is formed by directly etching explosion-proof notches on the side.

[0021] Figure 4 FIG. 4 is a top view of the battery casing of this embodiment.

[0022] Figure 5 Schematic diagram comparing the internal cavity of the battery casing of this embodiment with that of the battery casing of the prior art.

[0023] The accompanying drawings in the specification are numeraled as follows:

[0024] First side surface - 110; second side surface - 120; third side surface - 130; fourth side surface - 140; explosion-proof valve - 200; explosion-proof disk - 210; reinforcing boss - 210; first explosion-proof notch - 230; second explosion-proof notch - 250; side surface - 910; weld - 920. DETAILED DESCRIPTION

[0025] The following describes the implementation of the present invention through specific examples. The illustrations provided in the following embodiments are only used to schematically illustrate the basic concept of the present invention. The following embodiments and features in the embodiments may be combined with each other without conflict.

[0026] See also Figure 2 , Figure 2 It is a structural schematic diagram of an embodiment of an unequal-wall asymmetric ultra-thin high-strength battery shell of the utility model. The unequal-wall asymmetric ultra-thin high-strength battery shell of this embodiment includes a first side 110, a second side 120, a third side 130 and a fourth side 140, wherein the first side 110 is a thick side, and the second side 120, the third side 130 and the fourth side 140 are three thin sides respectively. The first side 110, the second side 120, the third side 130 and the fourth side 140 are enclosed to form a rectangular cylindrical structure with openings at both ends. Among them, the first side 110 and the third side 130 are arranged oppositely, and the second side 120 and the fourth side 140 are arranged oppositely. The widths of the first side 110 and the third side 130 are generally equal; the widths of the second side 120 and the fourth side 140 are generally equal.

[0027] The battery shell can be an integrally formed seamless structure, that is, there is no weld 920 on the first side 110, the second side 120, the third side 130 and the fourth side 140. In order not to form a weld 920 on the battery shell, an aluminum alloy material can be used to directly form a rectangular cylindrical structure as a battery shell by extrusion. However, since the battery shell directly formed by extrusion has a low strength, an aluminum alloy material can be used to first form a rectangular cylindrical structure by extrusion as a shell blank, and then the shell blank is formed into a battery shell of the desired size by cold drawing, thereby increasing the strength of the battery shell by adding a one-step cold drawing process. Of course, the battery shell can also be formed by melting and casting using a stainless steel material or an aluminum alloy material, and a battery shell with a seamless structure can also be obtained.

[0028] In the prior art, the side assembly is bent into a rectangular cylinder and then welded. Although the sealing performance at the weld 920 can be guaranteed in the short term, the wall thickness at the weld 920 is necessarily uneven. After long-term use, the weld may leak due to oxidation, corrosion and other reasons of the material at the thinner wall thickness. In this embodiment, the battery housing adopts an integrally formed seamless structure, which can effectively avoid this situation. In addition, since welding is not required, the thickness of the side surface can also be made thinner. For example, in this embodiment, the wall thickness of the second side surface 120, the third side surface 130 and the fourth side surface 140 has been reduced to 0.3 mm. Of course, with the advancement of technology, the wall thickness of the second side surface 120, the third side surface 130 and the fourth side surface 140 can be made thinner and will not be limited by the welding process of the weld 920.

[0029] The first side surface 110 is provided with an explosion-proof valve 200; specifically, the first side surface 110 is provided with an explosion-proof hole (not shown in the figure), the explosion-proof valve 200 is an explosion-proof disc 210 welded to close the explosion-proof hole, the outer edge of the explosion-proof disc 210 is provided with a reinforcing boss 210, and the explosion-proof disc 210 is formed with a first explosion-proof notch 230. Of course, please refer to Figure 3 Alternatively, the explosion-proof hole may not be provided on the first side surface 110 , but the explosion-proof valve 200 may be formed by directly etching the second explosion-proof notch 250 on the first side surface 110 .

[0030] In this embodiment, the width of the first side surface 110 is smaller than the width of the second side surface 120. When multiple batteries form a battery pack, the wider sides of the battery housing are generally attached together to reduce the size of the battery pack, making the wider side surface unsuitable for setting the explosion-proof valve 200. Therefore, the explosion-proof valve 200 is generally set on the narrower side surface. Of course, the explosion-proof valve 200 can also be set on the wider side surface when necessary, so the width of the first side surface 110 can also be greater than the width of the second side surface 120.

[0031] See also Figure 4 , the wall thickness of the first side surface 110 is greater than the wall thickness of the second side surface 120, the third side surface 130 and the fourth side surface 140, and the wall thickness of the second side surface 120, the third side surface 130 and the fourth side surface 140 are generally equal. Of course, the wall thickness of the second side surface 120, the third side surface 130 and the fourth side surface 140 may also be unequal, but the wall thickness of the second side surface 120, the third side surface 130 and the fourth side surface 140 will be less than the wall thickness of the first side surface 110.

[0032] In this embodiment, the battery housing is made of aluminum alloy, and the wall thickness of the first side surface 110 is generally in the range of 0.8 mm to 1.2 mm. In this embodiment, the wall thickness of the first side plate 110 is 0.8 mm. The wall thickness of the second side surface 120, the third side surface 130 and the fourth side surface 140 is generally 0.3 mm to 0.7 mm.

[0033] In this embodiment, the wall thicknesses of the four sides of the battery casing (i.e., the first side 110, the second side 120, the third side 130, and the fourth side 140) are no longer consistent, forming an asymmetric structure with unequal walls. The three sides where the explosion-proof valve 200 is not provided (i.e., the second side 120, the third side 130, and the fourth side 140) can be thinned to form three thin sides; the internal volume of the battery casing can be increased while the external dimensions remain unchanged, so that more battery materials can be loaded to increase the capacity of the battery; combined with the cold drawing process, an ultra-thin high-strength battery casing can be obtained. For example, in this embodiment, the cold drawing process is adopted to reduce the wall thickness of the second side 120, the third side 130, and the fourth side 140 to 0.3 mm. Please refer to Figure 5 The dotted line portion is the boundary of the internal cavity when the battery shell has the same external dimensions and the wall thicknesses of the four sides are equal. By comparison, it can be clearly seen that after adopting the structure of this embodiment, the size of the internal cavity of the battery shell is increased, that is, the internal accommodation space of the battery shell is increased.

[0034] In addition, by thinning the three sides without explosion-proof valves 200 to form three thin sides, the material cost of the battery housing can be reduced. Although the increased capacity and reduced material cost of each battery are limited, for products such as new energy vehicles that require a large number of batteries, the increased battery capacity and reduced material cost after accumulation are still very obvious.

[0035] The utility model also discloses a secondary battery, which can be a power battery or an energy storage battery, for example, a blade battery. The shell of the secondary battery adopts the unequal-wall asymmetric ultra-thin high-strength battery shell of any of the above embodiments. Of course, the secondary battery also includes a battery cell accommodated in the battery shell and other structures necessary for conventional secondary batteries, which are all prior art and will not be described in detail here.

[0036] The utility model also discloses an electric device, which includes a secondary battery of any of the above embodiments, so as to supply power to the electric device through the secondary battery. For example, the electric device may be a new energy electric vehicle or a hybrid vehicle. It is understood that the electric device may also be an electric tool, an energy storage device, a power device, or other devices driven by electricity, such as a mobile phone, a tablet computer, a computer, and a drone.

[0037] The above embodiments only express the preferred implementation of the utility model, and the description is relatively specific and detailed, but it cannot be understood as limiting the scope of the utility model patent. It should be pointed out that for ordinary technicians in this field, several modifications and improvements can be made without departing from the concept of the utility model, which all belong to the protection scope of the utility model. Therefore, the protection scope of the utility model patent shall be based on the attached claims.

Claims

1. An unequal-wall asymmetric ultra-thin high-strength battery casing, characterized in that: It comprises a thick side surface and three thin side surfaces, which together form a rectangular cylindrical structure with openings at both ends; an explosion-proof valve is arranged on the thick side surface, and the wall thickness of the thick side surface is greater than that of the three thin side surfaces.

2. The unequal-wall asymmetric ultra-thin high-strength battery casing according to claim 1, characterized in that: The battery housing is an integrally formed seamless structure.

3. The unequal-wall asymmetric ultra-thin high-strength battery casing according to claim 2, characterized in that: The battery housing is formed by extruding an aluminum alloy material, or by extruding an aluminum alloy material into a rectangular cylindrical structure and then cold drawing the structure.

4. The unequal-wall asymmetric ultra-thin high-strength battery casing according to claim 2, characterized in that: The battery shell is formed by melting and casting stainless steel or aluminum alloy.

5. The unequal-wall asymmetric ultra-thin high-strength battery casing according to claim 1, characterized in that: The thick side surface is the first side surface, and the three thin side surfaces are respectively the second side surface, the third side surface and the fourth side surface; the widths of the first side surface and the third side surface are equal, the widths of the second side surface and the fourth side surface are equal, and the width of the first side surface is smaller than the width of the second side surface; the wall thicknesses of the second side surface, the third side surface and the fourth side surface are all equal.

6. The unequal-wall asymmetric ultra-thin high-strength battery casing according to claim 1, characterized in that: The battery shell is made of aluminum alloy, the wall thickness of the thick side is 0.8mm-1.2mm, and the wall thickness of the thin side is 0.3mm-0.7mm.

7. The unequal-wall asymmetric ultra-thin high-strength battery casing according to claim 6, characterized in that: The wall thickness of the thick side surface is 0.8 mm, and the wall thickness of the thin side surface is 0.3 mm.

8. The unequal-wall asymmetric ultra-thin high-strength battery casing according to any one of claims 1 to 7, characterized in that: An explosion-proof hole is provided on the thick side surface, the explosion-proof valve is an explosion-proof plate which is welded to close the explosion-proof hole, a reinforcing boss is provided on the outer edge of the explosion-proof plate, and a first explosion-proof notch is formed on the explosion-proof plate.

9. A secondary battery, characterized in that: It comprises the unequal-wall asymmetric ultra-thin high-strength battery casing as described in any one of claims 1 to 8.

10. An electrical equipment, characterized in that: Comprising the secondary battery as claimed in claim 9.

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