Outer wrapping film for battery

Abstract

The utility model relates to an outer wrapping film for a battery. The outer wrapping film comprises an insulating film and a top cover patch positioned in the middle of the insulating film, the insulating film and the top cover patch are integrally formed; avoiding holes for avoiding the positive pole, the negative pole, the cell code and the anti-explosion valve are formed in the top cover patch; and the insulating film and the top cover patch wrap the whole battery. According to the utility model, the insulating property of the outer coating film of the battery is fully ensured, parts can be reduced, and short circuit of the battery can be avoided.

Description

Technical Field

[0001] The utility model relates to the technical field of battery manufacturing, and particularly relates to an outer wrapping film for a battery. Background Art

[0002] The outer shell of a square battery is usually made of pure aluminum or stainless steel. To provide insulation protection for the power battery and beautify the appearance of the power battery, the outer shell of the power battery is usually coated with an insulating protective film. There are usually two ways to wrap the film for existing square batteries: one is the "return" type film wrapping method that starts from the side of the battery cell and pastes insulating sheets at the bottom and top. In this film wrapping method, the insulating sheet pasted at the bottom is likely to fall off, making it difficult to play the roles of waterproofing and insulation, resulting in problems such as battery short circuit and even explosion; the other is the "U" type film wrapping method that starts from the bottom of the battery cell and folds the sides. In this method, although the problem of the bottom of the battery cell being exposed can be solved, the bottom corner is likely to warp after film wrapping, and in addition, the four corners of the top cover patch are also likely to warp after film wrapping, affecting the beauty and performance of the battery.

[0003] Application No.: 202223447203.4, Application Date: December 22, 2022, Name of the Utility Model Application: Outer Wrapping Film for Electrode Group and Lithium-Ion Battery, including a plurality of sub-film bodies connected end to end in sequence. Each sub-film body has a main body part covering the side of the electrode group and a folding ear part connected to one end of the main body part. The folding ear part can be bent from the side of the electrode group to the end face of the electrode group and adhered to the end face of the electrode group. The outer wrapping film of the utility model can, when the equipment positioning is inaccurate during the hot melting process, simply tear off the film body with inaccurate positioning and replace it, thereby reducing the usage amount of the outer wrapping film, reducing material waste, saving costs, and having a good use effect.

[0004] In the above prior art, at least two sub-film bodies are required, and the top of the electrode group cannot be covered, that is, the top cover patch and the sub-film body need to be set separately; when the sub-film bodies are combined to cover the electrode group, there are defects: the side width (or bottom width) of each sub-film body is half of the side width (or bottom width) of the electrode group, and it is extremely easy to cause gaps on the side (or bottom) of the electrode group due to errors, so the electrode group is not completely covered, which is neither beautiful nor affects the insulation effect, and needs to be torn off and replaced.

[0005] In addition, the sub-film bodies are fixed by means of end-to-end plug-in connection, and this connection method is not firm. Summary of the Utility Model

[0006] Aiming at the defects in the prior art that multiple sub-film bodies are required, the top of the electrode group cannot be covered, it is extremely easy to cause gaps on the side (or bottom) of the electrode group due to errors, resulting in the electrode group not being completely covered, and the connection method of the sub-film bodies is not firm, the purpose of the present utility model is to provide an outer wrapping film for a battery.

[0007] The technical solution provided by the present utility model is as follows:

[0008] An outer wrapping film for a battery, the outer wrapping film comprising an insulating film and a top cover patch located in the middle of the insulating film; the insulating film and the top cover patch are integrally formed; the top cover patch is provided with avoidance holes for avoiding the positive electrode column, the negative electrode column, the battery cell code, and the explosion-proof valve; the insulating film and the top cover patch wrap the battery as a whole.

[0009] Further, taking the center of the top cover patch as the origin, the extending direction of the short side of the top cover patch as the X-axis, and the extending direction of the long side of the top cover patch as the Y-axis; the top cover patch is provided with first side surfaces on both sides along the X-axis; the first side surfaces correspond to the side surfaces of the battery.

[0010] Further, the insulating film includes a first front surface and a first bottom surface which are located on one side of the top cover patch and are arranged in sequence along the X-axis direction; the first front surface is provided with second side surfaces on both sides in the X-axis direction; the first front surface, the first bottom surface, and the second side surfaces respectively correspond to the front surface, the bottom surface, and the side surface of the battery.

[0011] Further, the common edge of the first side surface and the second side surface is a first tearable edge.

[0012] Further, the insulating film further includes a second front surface and a second bottom surface which are located on the other side of the top cover patch and are arranged in sequence along the X-axis direction; the second front surface is provided with third side surfaces on both sides in the X-axis direction; the second bottom surface is provided with fourth side surfaces on both sides in the X-axis direction; the second front surface and the second bottom surface correspond to the front surface and the bottom surface of the battery; the third side surfaces and the fourth side surfaces correspond to the side surfaces of the battery.

[0013] Further, the common edge of the first side surface and the third side surface is a second tearable edge; the common edge of the third side surface and the fourth side surface is a third tearable edge.

[0014] Further, when the outer wrapping film wraps the square battery as a whole, the second side surface and the third side surface partially overlap with the first side surface; the third side surface partially overlaps with the second side surface; the second side surface and the third side surface partially overlap with the fourth side surface.

[0015] Further, the first front surface and the top cover patch are separated by a first crease; the first front surface and the first bottom surface are separated by a second crease; the first front surface and the second side surface are separated by a third crease.

[0016] Further, the second front surface and the top cover patch are separated by a fourth crease; the second front surface and the second bottom surface are separated by a fifth crease; the second front surface and the third side surface are separated by a sixth crease; the second bottom surface and the fourth side surface are separated by a seventh crease.

[0017] Further, the boundary of the second side is stepped; the second side is provided with a first horizontal edge and a second horizontal edge along the X-axis direction; the vertical distance between the first horizontal edge and the third crease is less than the vertical distance between the second horizontal edge and the third crease; the vertical distance between the second horizontal edge and the third crease is a, and the width of the battery side is b, where 0.5b < a < 0.75b.

[0018] Adopting the technical solution provided by the present utility model, compared with the prior art, it has the following beneficial effects:

[0019] The outer packaging film of the present utility model includes an insulating film and a top cover patch, which are integrally formed, fully ensuring the insulating performance of the battery outer packaging film. It can not only reduce the number of components but also avoid the occurrence of battery short circuits. The insulating film is provided with creases and an easy-to-tear edge to avoid errors during wrapping. Considering that the side of the insulating film is prone to incomplete wrapping, the side of the insulating film in this application includes a first side, a second side, a third side, and a fourth side. The second side, the third side and the first side, between the first side and the third side, the second side, the third side and the fourth side all partially overlap, thus ensuring that the sides of the square battery are completely wrapped. Description of the Drawings

[0020] Figure 1 It is a schematic diagram of the overall structure of an outer packaging film for a battery according to this application;

[0021] Figure 2 It is a schematic diagram of the overall structure of an outer packaging film for a battery with creases according to this application;

[0022] Figure 3 It is a front view after the overall wrapping of the outer packaging film of this application;

[0023] Figure 4 It is a side view after the overall wrapping of the outer packaging film of this application;

[0024] Figure 5 It is a three-dimensional view after the overall wrapping of the outer packaging film of this application.

[0025] Explanation of the reference numerals in the schematic diagram:

[0026] Insulating film 1, first front surface 11, side surface 12, first side surface 121, second side surface 122, third side surface 123, fourth side surface 124, first bottom surface 13, second front surface 14, second bottom surface 15;

[0027] Top cover patch 2, positive electrode avoidance hole 21, negative electrode avoidance hole 22, cell code avoidance hole 23, explosion-proof valve avoidance hole 24;

[0028] First crease 31, second crease 32, third crease 33, fourth crease 34, fifth crease 35, sixth crease 36, seventh crease 37. Detailed implementation mode

[0029] To further understand the content of the present utility model, the present utility model will be described in detail in combination with the accompanying drawings and embodiments.

[0030] The structures, proportions, sizes, etc. shown in the drawings of this specification are only used to cooperate with the content disclosed in the specification for those familiar with this technology to understand and read, and are not used to limit the limiting conditions under which the present invention can be implemented. Therefore, they do not have technical essence. Any modification of the structure, change of the proportional relationship or adjustment of the size, without affecting the effects that the present invention can produce and the purposes that can be achieved, should still fall within the scope that can be covered by the technical content disclosed in the present utility model. At the same time, terms such as "upper", "lower", "left", "right", "middle", etc. cited in this specification are only for the convenience of clear narration and are not used to limit the scope that can be implemented. The change or adjustment of their relative relationship, without substantial change in the technical content, should also be regarded as the scope that the present invention can be implemented.

[0031] An outer packaging film for a battery of the present application includes an insulating film 1 and a top cover patch 2, which are integrally formed, fully ensuring the insulating performance of the battery outer packaging film, which can not only reduce parts but also avoid short circuits of the battery. The top cover patch 2 is provided with avoidance holes for avoiding the positive electrode column, negative electrode column, battery cell code, and explosion-proof valve. The avoidance holes include a positive electrode avoidance hole 21, a negative electrode avoidance hole 22, a battery cell code avoidance hole 23, and an explosion-proof valve avoidance hole 24.

[0032] The insulating film 1 is provided with creases to avoid errors during wrapping, and the battery side edges can be conveniently and quickly aligned along the creases.

[0033] Taking the center of the top cover patch 2 as the origin, and defining the extension direction of its short side as the X-axis and the extension direction of its long side as the Y-axis, the top cover patch 2 is provided with first side surfaces 121 on both sides in the X-axis direction, and the first side surfaces correspond to the battery side surfaces.

[0034] On one side of the top cover patch 2, along the X-axis direction, the insulating film includes a first front surface 11 and a first bottom surface 13 arranged in sequence. The first front surface 11 is provided with a second side surface 122 in the X-axis direction; on the other side of the top cover patch 2, along the X-axis direction, the insulating film 1 further includes a second front surface 14 and a second bottom surface 15 arranged in sequence. The second front surface 14 is provided with third side surfaces 123 on both sides in the X-axis direction, and the second bottom surface 15 is symmetrically provided with fourth side surfaces 124 on both sides in the X-axis direction. The first front surface 11 and the second front surface 14 can completely cover the front surface of the battery.

[0035] In order to overcome the possible errors during the wrapping process of the outer packaging film and avoid the situation that the battery is not completely wrapped, the insulating film 1 is provided with a first bottom surface 13 and a second bottom surface 15, which can ensure that the bottom surface of the battery is completely wrapped.

[0036] The insulating film 1 further includes side surfaces 12, namely a first side surface 121, a second side surface 122, a third side surface 123, and a fourth side surface 124, which are used to avoid the situation where the sides of the battery are not completely covered.

[0037] During wrapping, the first side surface 121 is wrapped over the second side surface 122 and the third side surface 123, and there is partial overlap between the first side surface 121 and the second side surface 122 and the third side surface 123; there is also partial overlap between the second side surface 122 and the third side surface 123 along the height direction of the battery; the fourth side surface 124 is wrapped over the second side surface 122 and the third side surface 123, and there is partial overlap between the fourth side surface 124 and the second side surface 122 and the third side surface 123. Therefore, the sides 12 of the battery can be completely covered.

[0038] The insulating film 1 includes a first crease 31, a second crease 32, and a third crease 33; the first front surface 11 and the top cover patch 2 are separated by the first crease 31, and the first crease 31 corresponds to the common edge of one of the fronts and the top surface of the battery; the first front surface 11 and the first bottom surface 13 are separated by the second crease 32, and the second crease 32 corresponds to the common edge of the same front and the bottom surface of the battery; the first front surface 11 and the second side surface 122 are separated by the third crease 33, and the third crease 33 corresponds to the common edge of the same front and the side surface of the battery.

[0039] The insulating film 1 further includes a fourth crease 34, a fifth crease 35, a sixth crease 36, and a seventh crease 37; the second front surface 14 and the top cover patch 2 are separated by the fourth crease 34, and the fourth crease 34 corresponds to the common edge of the second front and the top surface of the battery; the second front surface 14 and the second bottom surface 15 are separated by the fifth crease 35, and the fifth crease 35 corresponds to the common edge of the second front and the bottom surface of the battery; the second front surface 14 and the third side surface 123 are separated by the sixth crease 36, and the sixth crease 36 corresponds to the common edge of the second front and the side surface of the battery; the second bottom surface 15 and the fourth side surface 124 are separated by the seventh crease 37, and the seventh crease 37 corresponds to the common edge of the bottom surface and the side surface of the battery.

[0040] The insulating film 1 is also provided with a first tear edge 16, a second tear edge 17, and a third tear edge 18. The insulating film 1 can be easily torn along the first tear edge 16, the second tear edge 17, and the third tear edge 18, without causing the corners of the insulating film to warp.

[0041] The first tear edge 16 is the common edge of the first side surface 121 and the second side surface 122, the second tear edge 17 is the common edge of the first side surface 121 and the third side surface 123, and the third tear edge 18 is the common edge of the third side surface 123 and the fourth side surface 124.

[0042] Furthermore, the boundary of the second side surface 122 is stepped, and the second side surface 122 is provided with a first horizontal edge and a second horizontal edge along the X-axis direction, and the vertical distance between the first horizontal edge and the third crease 33 is smaller than the vertical distance between the second horizontal edge and the third crease 33; the vertical distance between the second horizontal edge and the third crease 33 is a, and the width of the battery side is b, 0.5b<a<0.75b.

[0043] Furthermore, the boundary of the third side surface 123 is stepped, and the third side surface 123 is provided with a third horizontal edge and a fourth horizontal edge along the X-axis direction, and the vertical distance between the third horizontal edge and the sixth fold 36 is smaller than the vertical distance between the fourth horizontal edge and the sixth fold 36; the vertical distance between the fourth horizontal edge and the sixth fold 36 is c, and the width of the battery side surface is d, 0.5d<c<0.75d.

[0044] Through the above configuration, it is ensured that the second side surface 122 and the third side surface 123 partially overlap along the height direction of the battery, thereby preventing the battery from being partially exposed due to operating errors.

[0045] The first side surface 121 is also provided with a first hypotenuse and a second hypotenuse, which are symmetrical to each other and connected by a fifth horizontal side. The angle formed by the first hypotenuse or the second hypotenuse and the fifth horizontal side is 60° to 75°. Such a setting can further prevent the four corners from curling up when the insulating film is wrapped.

[0046] Preferably, the first side surface 121 and the fourth side surface 124 have the same shape, and the second side surface 122 and the third side surface 123 have the same shape, so that the battery has a neat and beautiful appearance after being wrapped.

[0047] The above schematically describes the present invention and its implementation methods, which are not restrictive. The drawings show only one implementation method of the present invention, and the actual structure is not limited thereto. Therefore, if ordinary technicians in this field are inspired by it and design structural methods and embodiments similar to the technical solution without creativity without departing from the purpose of the present invention, they should all fall within the protection scope of the present invention.

Claims

1. An outer film for a battery, characterized in that: The outer film comprises an insulating film (1) and a top cover patch (2) located in the middle of the insulating film (1); the insulating film (1) and the top cover patch (2) are integrally formed; the top cover patch (2) is provided with a evacuation hole for evading a positive pole, a negative pole, a cell code, and an explosion-proof valve; the insulating film (1) and the top cover patch (2) envelop the battery as a whole; The center of the top cover patch (2) is taken as the origin, the direction in which the short side of the top cover patch (2) extends is the X-axis, and the direction in which the long side of the top cover patch (2) extends is the Y-axis; the top cover patch (2) is provided with first side surfaces (121) on both sides along the X-axis direction; the first side surfaces (121) correspond to the side surfaces of the battery; The insulating film (1) comprises a first front surface (11) and a first bottom surface (13) which are located on one side of the top cover patch (2) and are arranged in sequence along the X-axis direction; the first front surface (11) is provided with second side surfaces (122) on both sides thereof in the X-axis direction; The common edge between the first side surface (121) and the second side surface (122) is a first tearable edge (16); The insulating film (1) further comprises a second front surface (14) and a second bottom surface (15) which are located on the other side of the top cover patch (2) and are arranged in sequence along the X-axis direction; the second front surface (14) is provided with third side surfaces (123) on both sides of the X-axis direction; and the second bottom surface (15) is provided with fourth side surfaces (124) on both sides of the X-axis direction; The common edge between the first side surface (121) and the third side surface (123) is the second easy-tear edge (17); the common edge between the third side surface (123) and the fourth side surface (124) is the third easy-tear edge (18); When the outer film covers the entire square battery, the second side surface (122) and the third side surface (123) partially overlap with the first side surface (121); the third side surface (123) partially overlaps with the second side surface (122); and the second side surface (122) and the third side surface (123) partially overlap with the fourth side surface (124).

2. The outer film for a battery according to claim 1, characterized in that: The first front surface (11), the first bottom surface (13), and the second side surface (122) correspond to the front surface, the bottom surface, and the side surface of the battery, respectively.

3. The outer film for a battery according to claim 1, characterized in that: The second front surface (14) and the second bottom surface (15) correspond to the front surface and the bottom surface of the battery; the third side surface (123) and the fourth side surface (124) correspond to the side surfaces of the battery.

4. The outer film for a battery according to claim 1, characterized in that: The first front surface (11) and the top cover patch (2) are separated by a first fold (31); the first front surface (11) and the first bottom surface (13) are separated by a second fold (32); and the first front surface (11) and the second side surface (122) are separated by a third fold (33).

5. The outer film for a battery according to claim 1, characterized in that: The second front surface (14) and the top cover patch (2) are separated by a fourth fold (34); the second front surface (14) and the second bottom surface (15) are separated by a fifth fold (35); the second front surface (14) and the third side surface (123) are separated by a sixth fold (36); and the second bottom surface (15) and the fourth side surface (124) are separated by a seventh fold (37).

6. The outer film for a battery according to claim 1, characterized in that: The boundary of the second side surface (122) is step-shaped; the second side surface (122) is provided with a first horizontal edge and a second horizontal edge along the X-axis; the vertical distance between the first horizontal edge and the third fold (33) is smaller than the vertical distance between the second horizontal edge and the third fold (33); the vertical distance between the second horizontal edge and the third fold (33) is a, the width of the battery side surface is b, and 0.5b<a<0.75b.

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