Battery protection bag and battery

Abstract

The utility model belongs to the field of batteries, and particularly relates to a battery protection bag and a battery. The battery protection bag comprises a bag body with an opening at one end; the open end of the bag body is in a plain end design; a frosted hot melting area is arranged at the opening end of the bag body. The battery protection bag (protection bag for short) is easy to manufacture, the assembly process is simplified, and the production efficiency can be improved; due to the plain end design of the open end, the naked battery cell can be directly put into the protection bag, and compared with a mylar film, the procedures of film folding and rubber coating are omitted.

Description

Technical Field

[0001] The utility model belongs to the field of batteries, and in particular relates to a battery protection bag and a battery. Background Art

[0002] Square aluminum shell batteries are the current mainstream lithium-ion batteries. During the manufacturing process, bare cells need to be covered with an insulating film to achieve insulation, dust and metal particle protection functions.

[0003] Common insulating films include my l ar film or direct use of tape for covering and isolation. The functional principle of the my l ar film is to fold the my l ar film and then wrap the bare battery cell, and finally fix the my l ar film and the bare battery cell with tape or hot melt; however, the corresponding process is complicated, and the bottom corners of the bare battery cell are not completely covered, and there are lithium ion conduction channels. At the same time, after folding, it becomes an open rectangular body, and there is a risk of scratching when entering the shell. Moreover, the bottom angle of the film is 90° after folding, and it interferes with the chamfer of the battery shell after entering the shell, and is squeezed by gravity to generate a force acting on the bare battery cell; therefore, there is a risk of corrosion between the bare battery cell and the shell during the process or use of the battery cell. Utility Model Content

[0004] The purpose of the utility model is to overcome the defects in the prior art and provide a battery protection bag and a battery.

[0005] In order to achieve the above-mentioned purpose, the present invention adopts the following technical solutions:

[0006] A battery protection bag includes a bag body with an open end; the bag body includes two large surfaces, two side surfaces disposed between the two large surfaces, and a first bottom surface connecting the side surfaces and the large surfaces; the open end of the bag body is flat and has a frosted hot-melt area.

[0007] The large surface, side surfaces and the first bottom surface are sealed and non-porous;

[0008] The thickness of the frosted hot-melt zone is greater than the thickness of the large surface.

[0009] The thickness of the large surface is 0.1-0.5 mm, the thickness of the side surface is 0.1-0.8 mm, and the thickness of the first bottom surface is 0.4-2 mm.

[0010] The frosted hot-melt zone has a thickness of 0.3-0.8 mm and is rectangular.

[0011] The bottom surface of the bag body is designed to be flat; the bottom of the bag body is provided with a chamfer, and the chamfer angle is 90 degrees.

[0012] The chamfer radius between the large surface and the side surface is 0.5-4mm, the chamfer radius between the large surface and the first bottom surface is 0.5-3mm, and the chamfer radius between the side surface and the first bottom surface is 0.5-3mm.

[0013] The utility model also includes a battery, including a battery cell, a cover plate assembly connected to the battery cell, a battery protection bag wrapping the battery cell, and a battery shell arranged on the outside of the battery protection bag; the frosted hot melt area is connected to the cover plate assembly.

[0014] The bag body includes two large surfaces, two side surfaces arranged between the two large surfaces, and a second bottom surface connecting the side surfaces and the large surfaces; a bottom support plate is arranged between the second bottom surface and the battery cell; the thickness of the bottom support plate is 0-1.6mm, and the thickness of the second bottom surface is 0.1-0.4mm; preferably, as an alternative, the sum of the thickness of the bottom support plate and the second bottom surface is equal to the thickness of the first bottom surface.

[0015] Compared with the prior art, the beneficial effects of the present invention are:

[0016] The battery protection bag (hereinafter referred to as the protection bag) of this utility model is easy to manufacture, simplifies the assembly process, and can improve production efficiency. The flat design of the opening end allows bare batteries to be placed directly into the protection bag, eliminating the film folding and encapsulation steps compared to Mylar film. Furthermore, compared with non-flat designs, the protection bag of this application is more conducive to hot-melting the lower plastic of the protection bag and cover assembly. The bottom corners are fully enclosed to reduce the possibility of shell corrosion. As a preferred form, the bottom corners are chamfered to facilitate shell insertion and reduce interference between the bottom corners of the battery cells and the internal chamfers of the shell. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] Figure 1 This is a schematic diagram of the overall structure of the battery protection bag of the utility model;

[0018] Figure 2 This is a side view of the battery protection bag of the present invention;

[0019] Figure 3 This is a schematic structural diagram of a battery of the present utility model;

[0020] Figure 4 This is a structural diagram of the bottom support plate of the present utility model;

[0021] In the figure, the frosted hot melt area 201, the bottom corner 202, the bag body 203, the side surface 204, the bottom surface 205, the large surface 200, the battery shell 100, the battery cell 400, and the cover assembly 500. DETAILED DESCRIPTION

[0022] In order to enable those skilled in the art to better understand the technical solution of the present invention, the present invention will be further described in detail below with reference to the accompanying drawings and the best embodiments.

[0023] Figure 1-2 A battery protection bag is shown, including a bag body 203 with an open end; the bag body 203 includes two large surfaces, two side surfaces 204 arranged between the two large surfaces 200, and a first bottom surface 205 connecting the side surfaces and the large surfaces; the thickness of the frosted hot melt area 201 is greater than the thickness of the large surface.

[0024] The opening end of the bag body 203 is designed to be flat; the opening end of the bag body is provided with a frosted hot-melt area 201 .

[0025] The thickness of the large surface is 0.1-0.5 mm, specifically 0.1 mm, 0.2 mm, 0.3 mm, 0.4 mm, or 0.5 mm;

[0026] The thickness of the side surface is 0.1-0.8mm, specifically 0.1mm, 0.4mm, 0.5mm, 0.6mm, 0.8mm;

[0027] The thickness of the first bottom surface is 0.4-2mm, specifically 0.4mm, 0.5mm, 1mm, 1.2mm, or 2mm; the thickness of the frosted hot-melt zone is 0.3-0.8mm, specifically 0.3mm, 0.4mm, 0.5mm, 0.6mm, or 0.8mm.

[0028] The bottom surface of the bag body is designed to be flat; the bottom of the bag body is provided with a chamfer, and the chamfer angle is 90 degrees.

[0029] The chamfer radius of the large surface and side surfaces is 0.5-4mm, specifically 0.5mm, 1mm, 2mm, 3mm, 4mm;

[0030] The chamfer radius between the large surface and the first bottom surface is 0.5-3mm, specifically 0.5mm, 1mm, 2mm, or 3mm;

[0031] The chamfer radius between the side surface and the first bottom surface is 0.5-3 mm, and can be specifically 0.5 mm, 1 mm, 2 mm, or 3 mm.

[0032] The frosted hot-melt area is rectangular.

[0033] Figure 3 A battery is shown, including a battery cell 400, a cover assembly 500 connected to the battery cell, the battery protection bag 203 wrapping the battery cell, and a battery shell 100 arranged on the outside of the battery protection bag 203; the frosted hot melt area 201 is connected to the cover assembly 500.

[0034] The battery of the present invention is particularly a square aluminum shell lithium ion battery, the structural diagram of which is shown in FIG. Figure 3 As shown, it is composed of a housing 100, a battery protection bag 203, a battery cell 400, and a cover assembly 500. The battery protection bag 203 is between the housing 100 and the battery cell 400 to isolate the battery cell 400 from the housing 100.

[0035] Battery assembly process: The battery cell 400 is welded to the cover assembly 500 and then placed in the battery protection bag 203. The frosted hot-melt area 201 at the open end of the battery protection bag 203 is hot-melted and adhered to the lower plastic of the cover assembly 500 to position and restrain the bare battery cell. Then the battery shell 100 is added and the battery is sealed by laser welding.

[0036] As an alternative, the thickness of the first bottom surface 205 of the battery protection bag can be reduced by adding a bottom support plate 300 (such as Figure 4 The bag body includes two large surfaces, two side surfaces arranged between the two large surfaces, and a second bottom surface connecting the side surfaces and the large surfaces; a bottom support plate 300 is arranged between the second bottom surface and the battery cell; the thickness of the bottom support plate is 0-1.6mm, and the thickness of the second bottom surface is 0.1-0.4mm; preferably, as an alternative solution, the sum of the thickness of the bottom support plate and the second bottom surface is equal to the thickness of the first bottom surface. For example, if the thickness of the first bottom surface is 0.4mm, the thickness of the bottom support plate is 0.2mm, and the thickness of the second bottom surface is 0.2mm.

[0037] The working principle of the present invention is as follows: the battery protection bag is only open at the top, which can prevent welding slag from entering the battery cell, while the other surfaces are fully sealed, avoiding the potential shell corrosion problem caused by the incomplete sealing of the bottom corners of the traditional my l ar film; the four bottom corners 202 of the battery protection bag are optimized according to the internal chamfers of the shell, which facilitates the entry of the coated bare battery cell into the shell, reduces the risk of the battery cell hitting the shell and injuring it, reduces the risk of the protection bag accumulating between the bottom of the bare battery cell 400 and the bottom corner of the shell 100, and improves the flatness of the bottom electrode of the bare battery cell;

[0038] The flat-mouth design of the battery protection bag 203 facilitates frosting and thickening of the top of the hot-melt battery protection bag to obtain a frosted hot-melt area 201. The thickening ensures that the frosted hot-melt area 201 of the battery protection bag will not break when it is pasted to the lower plastic of the cover assembly 500 after hot-melting, thereby reducing the difficulty of production. The frosting realizes the hot-melt position positioning, reduces the risk of misalignment of the protection bag relative to the bare battery cell, and ensures the flatness of the protection bag on the large surface of the bare battery cell.

[0039] The following is described with specific examples:

[0040] Example 1

[0041] Battery protection bag 203 (such as Figure 1, 2), including a bottom surface 205, two large surfaces 200, and two side surfaces 204, a total of five surfaces forming a rectangular body with an upper opening. The four bottom corners 202 formed by the large surface, the first bottom surface, and the side surfaces of the battery protection bag are closed chamfered at a certain angle.

[0042] The battery protective bag has a flat top opening, with the large surface 200 and the upper portions of the side surfaces 204 flush. The large surface and side surfaces feature four frosted hot-melt areas 201. During battery assembly, cells can be placed directly into the protective bag. This simplifies the bare cell wrapping process compared to the traditional Mylar film wrapping process, eliminating the folding and gluing steps and improving production efficiency.

[0043] In some embodiments, the battery protective pouch has a thickness of 0.1-0.5 mm on the large surface 203, 0.1-0.8 mm on the side surfaces 204, and 0.4-2 mm on the bottom surface. The large surface and upper portions of the side surfaces are flat. This flat design facilitates a smooth hot-melt area when the battery protective film is hot-melted to the plastic under the cover assembly, improving the yield rate of the hot-melt process.

[0044] Furthermore, a frosted hot-melt area 201 is provided on the large surface and the upper portion of the side surface 204 of the battery protection bag 203 , and the thickness of the frosted hot-melt area 201 is 0.3-0.8 mm.

[0045] The frosted hot melt zone design enables intelligent identification of the hot melt location of the insulating film during battery assembly, improving hot melt efficiency and reducing the risk of large-scale unevenness on the battery cell surface. The relatively high thickness of the hot melt area reduces the risk of film breakage during hot melt.

[0046] Furthermore, the battery protection bag 203, with the exception of the top opening, has five sealed surfaces without holes. The battery protection bag 203 is integrally formed, making the large surface, first bottom surface, and side surfaces sealed without holes. This prevents the bare battery cells from being connected to the casing through scattered foreign matter such as graphite, metal, and dust, thus preventing casing corrosion.

[0047] Furthermore, the four bottom corners 202 of the battery protection bag 203 are chamfered at a certain angle of 90°, and the chamfer radius between the large surface 203 and the side surface 204 is 0.5-4mm, the chamfer radius between the large surface 203 and the first bottom surface 205 is 0.5-3mm, and the chamfer radius between the side surface 204 and the first bottom surface 205 is 0.5-3mm.

[0048] By chamfering the bottom corners 202 of the battery protection bag, the battery cell is placed into the shell more smoothly, reducing the risk of the cell hitting the shell during battery assembly. The chamfered design reduces the accumulation of bare battery cells at the bottom corners of the battery protection bag during the insertion process, and improves the flatness of the bottom electrode of the bare battery cell.

[0049] In the second aspect, the present invention preferably has a battery case 100 having the above-mentioned cell protection bag. The case material is preferably metal aluminum, the top of the case is open, and the chamfers between the surfaces are as small as possible within the process capability.

[0050] The frosted hot-melt zone 201 edge of the battery protection bag is welded to the cover plate to isolate the battery cell from the shell, reducing the risk of metal welding slag falling into the bare battery cell and causing the battery cell to contact metal foreign matter.

[0051] In a third aspect, the present invention preferably includes a battery having the aforementioned cell protection bag and housing. The cell protection bag completely covers all surfaces of the cell, including the large surface, side surfaces, and first bottom surface. The upper portion is heat-fused to the plastic under the cover plate, preventing the cell from contacting foreign matter such as metal, graphite, and dust, thereby reducing the battery's self-discharge rate and the risk of housing corrosion. The housing has an open top, allowing the bare cell, after being coated, to be placed within it to protect the cell assembly.

[0052] In summary, the battery protection bag (hereinafter referred to as the protection bag) of the present invention is easy to manufacture, simplifies the assembly process, and can improve production efficiency. The flat-end design of the opening allows bare cells to be placed directly into the protection bag, eliminating the film folding and encapsulation steps compared to mylar film. Furthermore, compared to non-flat-end designs, the protection bag of the present application is more conducive to hot-melting the lower plastic of the protection bag and cover assembly. The bottom corners are fully enclosed to reduce the possibility of shell corrosion. As a preferred form, the chamfered bottom corners facilitate shell insertion and reduce interference between the bottom corners of the battery cell and the internal chamfer of the shell.

[0053] The above contents are only preferred embodiments of the present invention. For ordinary technicians in this field, according to the concept of the present invention, there may be changes in the specific implementation methods and application scope. The content of this specification should not be understood as limiting the present invention.

Claims

1. A battery protection bag, characterized in that: It comprises a bag body with an open end; the open end of the bag body is designed to be flat; the bag body comprises two large surfaces, two side surfaces arranged between the two large surfaces, and a first bottom surface connecting the side surfaces and the large surfaces; the open end of the bag body is provided with a frosted hot-melt area.

2. The battery protection bag according to claim 1, characterized in that: The large surface, side surfaces and first bottom surface are sealed and non-porous.

3. The battery protection bag according to claim 1, characterized in that: The thickness of the frosted hot-melt zone is greater than the thickness of the large surface.

4. The battery protection bag according to claim 1, characterized in that: The thickness of the large surface is 0.1-0.5 mm, the thickness of the side surface is 0.1-0.8 mm, and the thickness of the first bottom surface is 0.4-2 mm.

5. The battery protection bag according to claim 1, characterized in that: The thickness of the frosted hot-melt zone is 0.3-0.8 mm; the frosted hot-melt zone is rectangular.

6. The battery protection bag according to claim 1, characterized in that: The first bottom surface of the bag body is designed to be flat, and the bottom is provided with a chamfer with a chamfer angle of 90°.

7. The battery protection bag according to claim 6, characterized in that: The chamfer radius between the large surface and the side surface is 0.5-4mm, the chamfer radius between the large surface and the first bottom surface is 0.5-3mm, and the chamfer radius between the side surface and the first bottom surface is 0.5-3mm.

8. A battery, characterized in that: It includes a battery cell, a cover plate assembly connected to the battery cell, a battery protection bag according to any one of claims 1 to 7 that wraps the battery cell, and a battery shell arranged on the outside of the battery protection bag; the frosted hot melt area is connected to the cover plate assembly.

9. The battery according to claim 8, characterized in that The bag body includes two large surfaces, two side surfaces arranged between the two large surfaces, and a second bottom surface connecting the side surfaces and the large surfaces; a bottom support plate is arranged between the second bottom surface and the battery cell; the thickness of the bottom support plate is 0-1.6mm, and the thickness of the second bottom surface is 0.1-0.4mm.

10. The battery according to claim 9, characterized in that The sum of the thicknesses of the bottom supporting plate and the second bottom surface is equal to the thickness of the first bottom surface.

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