Mylar membrane and battery

Abstract

The Mylar membrane comprises a side wall wrapping membrane and a bottom wall wrapping membrane which are used for wrapping a battery cell, the battery cell is provided with a bottom wall, a top wall and a side wall, the bottom wall and the top wall are oppositely arranged, the side wall is arranged between the bottom wall and the top wall, and the side wall wrapping membrane is used for being attached to the side wall. The bottom wall wrapping membrane is used for being attached to the bottom wall, the side wall wrapping membranes are arranged on the two sides of the bottom wall wrapping membrane respectively and connected with the bottom wall wrapping membrane, and first glue layers are arranged at the positions, close to the top wall, of the side wall wrapping membranes. A second adhesive layer is arranged at the joint of one side wall wrapping membrane and the other side wall wrapping membrane, and a plurality of permeation holes are formed in the bottom wall wrapping membrane. According to the Mylar film disclosed by the utility model, the traditional step of hot melting point glue can be omitted, the production time of a battery cell is shortened, the bonding area is increased, and the bonding strength is increased.

Description

Technical Field

[0001] The utility model relates to the field of new energy, in particular to Mylar and a battery. Background Art

[0002] With the development of the new energy market, the market share of electric vehicles is getting higher and higher, and the demand for power lithium-ion batteries is increasing. At present, square aluminum shell batteries have the highest market share. The outer wall of the core package of the square aluminum shell battery is generally wrapped with Mylar film. The Mylar film is used to prevent the bare core package from being scratched by the side of the aluminum shell during the shelling and later use. In addition, the Mylar film can also prevent the core package from directly contacting the aluminum shell to play an insulating protection role. The Mylar film material is one of PP, PC, PET, and PVC insulation sheets. It is generally fixed together with the cover plate by hot melting. It has the following defects: the hot melting process between the Mylar film and the cover plate is relatively complicated, and the hot melting process is affected by factors such as temperature, pressure and material. If the process parameters are not properly matched, the Mylar film is prone to over-melting and drawing, the Mylar film is hot-melted and bulged, and the Mylar film falls off due to insufficient hot melting. The hot melt process involves multiple steps such as coating, melting, and curing of hot melt adhesive. These steps not only increase the difficulty of operation, but also may lead to reduced production efficiency. The curing process of hot melt adhesive often takes a certain amount of time, which further prolongs the production cycle of the battery. Therefore, how to design a structure that can solve the above problems is an urgent problem to be solved. Utility Model Content

[0003] The purpose of the utility model is to provide a Mylar film and a battery that solve the above problems.

[0004] To achieve the above purpose, the utility model provides the following technical solutions:

[0005] A Mylar film, the Mylar film comprising a side wall wrapping film sheet and a bottom wall wrapping film sheet for wrapping a battery cell, the battery cell having a bottom wall and a top wall arranged opposite to each other, and a side enclosure arranged between the bottom wall and the top wall, the side wall wrapping film sheet being used to fit the side enclosure, the bottom wall wrapping film sheet being used to fit the bottom wall, the side wall wrapping film sheets being respectively arranged on both sides of the bottom wall wrapping film sheet and connected to the side wall wrapping film sheets, a first adhesive layer being arranged at a position of the side wall wrapping film sheet close to the top wall, and a second adhesive layer being arranged at a connection between the side wall wrapping film sheet and another side wall wrapping film sheet, and a plurality of penetration holes being opened on the bottom wall wrapping film sheet.

[0006] Preferably, the side enclosure includes a front wall and a rear wall that are relatively arranged, and a left wall and a right wall that are relatively arranged; the side wall wrapping film includes a first front wall wrapping film sheet and a second front wall wrapping film sheet for fitting the front wall, a first rear wall wrapping film sheet and a second rear wall wrapping film sheet for fitting the rear wall, a left wall wrapping film sheet for fitting the left wall, and a right wall wrapping film sheet for fitting the right wall, and the left wall wrapping film sheet and the right wall wrapping film sheet are respectively connected to the bottom wall wrapping film sheet.

[0007] Preferably, the left wall wrapping film sheet is arranged between the first front wall wrapping film sheet and the first rear wall wrapping film sheet, and are respectively connected to the left wall wrapping film sheet; the right wall wrapping film sheet is arranged between the second front wall wrapping film sheet and the second rear wall wrapping film sheet, and are respectively connected to the right wall wrapping film sheet.

[0008] Preferably, a first folded edge is provided between the left wall wrapping film sheet and the first front wall wrapping film sheet, as well as the first rear side wall wrapping film sheet; a second folded edge is provided between the right wall wrapping film sheet and the second front wall wrapping film sheet, as well as the second rear side wall wrapping film sheet.

[0009] Preferably, the area of ​​the first front wall wrapping film sheet and the second front wall wrapping film sheet is larger than the area of ​​the second one; the area of ​​the first rear wall wrapping film sheet and the second rear wall wrapping film sheet is larger than the area of ​​the second one.

[0010] Preferably, a second adhesive layer is provided on one of the first front wall wrapping film sheet and the second front wall wrapping film sheet; and a second adhesive layer is provided on one of the first rear wall wrapping film sheet and the second rear wall wrapping film sheet.

[0011] The utility model also provides a battery, comprising a battery core and the Mylar film, wherein the Mylar film is used for wrapping the battery core.

[0012] The beneficial effects of the utility model are as follows: the Mylar film of the utility model can save the traditional hot-melt glue dispensing step, shorten the production time of the battery core, increase the bonding area, and increase the bonding strength. BRIEF DESCRIPTION OF THE DRAWINGS

[0013] Figure 1 It is a structural schematic diagram of the utility model;

[0014] Among them, the side wall wrapping membrane 1, the bottom wall wrapping membrane 2, the first adhesive layer 3, the second adhesive layer 4, the penetration hole 5, the first front wall wrapping membrane 6, the second front wall wrapping membrane 7, the first rear wall wrapping membrane 8, the second rear wall wrapping membrane 9, the left wall wrapping membrane 10, the right wall wrapping membrane 11, the first folding edge 12, the second folding edge 13, DETAILED DESCRIPTION

[0015] The technical solution of this patent is further described in detail below in conjunction with specific implementation methods.

[0016] It is to be understood that the specific embodiments described herein are only used to explain the present invention, rather than to limit the present invention. It should also be noted that, for ease of description, only parts related to the present invention, rather than all structures, are shown in the accompanying drawings.

[0017] In the description of the present invention, unless otherwise clearly specified and limited, the terms "connected", "connected", and "fixed" should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection or an indirect connection through an intermediate medium, it can be the internal connection of two elements or the interaction relationship between two elements. For ordinary technicians in this field, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.

[0018] In the present utility model, unless otherwise clearly specified and limited, a first feature being "above" or "below" a second feature may include that the first and second features are in direct contact, or may include that the first and second features are not in direct contact but are in contact through another feature between them. Moreover, a first feature being "above", "above" and "above" a second feature includes that the first feature is directly above and obliquely above the second feature, or simply indicates that the first feature is higher in level than the second feature. A first feature being "below", "below" and "below" a second feature includes that the first feature is directly below and obliquely below the second feature, or simply indicates that the first feature is lower in level than the second feature.

[0019] In the description of this embodiment, the terms "upper", "lower", "left", "right" and other directions or positional relationships are based on the directions or positional relationships shown in the drawings, and are only for the convenience of description and simplified operation, rather than indicating or implying that the device or element referred to must have a specific direction, be constructed and operated in a specific direction, and therefore cannot be understood as a limitation of the present invention. In addition, the terms "first" and "second" are only used to distinguish in the description and have no special meaning.

[0020] like Figure 1 As shown, the utility model provides a Mylar film, which includes a side wall wrapping film sheet 1 and a bottom wall wrapping film sheet 2 for wrapping a battery cell (not shown). The battery cell has a bottom wall and a top wall arranged opposite to each other, and a side wall arranged between the bottom wall and the top wall, the side wall wrapping film sheet 1 is used to fit the side wall, and the bottom wall wrapping film sheet 2 is used to fit the bottom wall.

[0021] Furthermore, side wall wrapping film sheets 1 are respectively arranged on both sides of the bottom wall wrapping film sheet 2 and connected to the side wall wrapping film sheet 1. A first adhesive layer 3 is arranged on the side wall wrapping film sheet 1 near the top wall. The first adhesive layer 3 is used to connect to the cover plate arranged on the top wall of the battery cell after the Mylar film is folded to wrap the battery cell. A second adhesive layer 4 is arranged at the connection between the side wall wrapping film sheet 1 and another side wall wrapping film sheet 1. The second adhesive layer 4 can connect the two side wall wrapping film sheets after the Mylar film is folded to wrap the side of the battery cell. A plurality of penetration holes 5 for penetrating electrolyte are provided on the bottom wall wrapping film sheet 2. The first adhesive layer 3 and the second adhesive layer 4 of the utility model are adhesives such as PVDF or PMMA. The bonding connection between the cover plate and the side wall wrapping film sheet 1 is realized in the step of hot pressing the battery cell stack, eliminating the step of hot melt gluing.

[0022] The side enclosure includes a front wall and a rear wall that are arranged oppositely, and a left wall and a right wall that are arranged oppositely. The side wall wrapping film sheet 1 includes a first front wall wrapping film sheet 6 and a second front wall wrapping film sheet 7 for attaching to the front wall, a first rear wall wrapping film sheet 8 and a second rear wall wrapping film sheet 9 for attaching to the rear wall, a left wall wrapping film sheet 10 for attaching to the left wall, and a right wall wrapping film sheet 11 for attaching to the right wall. The left wall wrapping film sheet 10 and the right wall wrapping film sheet 11 are respectively connected to the two ends of the bottom wall wrapping film sheet 2.

[0023] Further, a left wall wrapping film sheet 10 is arranged between the first front wall wrapping film sheet 6 and the first rear wall wrapping film sheet 8, and is respectively connected to the left wall wrapping film sheet 10. A first folding edge 12 is arranged between the left wall wrapping film sheet 10 and the first front wall wrapping film sheet 6 and the first rear side wall wrapping film sheet 8. A right wall wrapping film sheet 11 is arranged between the second front wall wrapping film sheet 7 and the second rear wall wrapping film sheet 9, and is respectively connected to the right wall wrapping film sheet 11. A second folding edge 13 is arranged between the right wall wrapping film sheet 11 and the second front wall wrapping film sheet 7 and the second rear wall wrapping film sheet 9. The first folding edge 12 and the second folding edge 13 facilitate folding the film, and facilitate the side wall wrapping film sheet 1 to better fit the side periphery of the battery cell.

[0024] Further, the area of ​​the first front wall wrapping film sheet 6 and the second front wall wrapping film sheet 7 is greater than the area of ​​the second one. The area of ​​the first rear wall wrapping film sheet 8 and the second rear wall wrapping film sheet 9 is greater than the area of ​​the second one. A second adhesive layer 4 is provided on one of the first front wall wrapping film sheet 6 and the second front wall wrapping film sheet 7; a second adhesive layer 4 is provided on one of the first rear wall wrapping film sheet 8 and the second rear wall wrapping film sheet 9.

[0025] like Figure 1As shown, one embodiment of the utility model is: the area of ​​the first front wall wrapping film sheet 6 is larger than the area of ​​the second front wall wrapping film sheet 7; the area of ​​the first rear wall wrapping film sheet 8 is larger than the area of ​​the second rear wall wrapping film sheet 9. The first front wall wrapping film sheet 6 and the first rear wall wrapping film sheet are provided with a second adhesive layer 4, which is connected to the first adhesive layer 3 and is L-shaped. The two side wall wrapping film sheets 1 can be connected by the second adhesive layer 4, thereby wrapping the side periphery of the battery cell.

[0026] One embodiment of the utility model can also be: the area of ​​the first front wall wrapping film sheet 6 is larger than the area of ​​the second front wall wrapping film sheet 7; the area of ​​the first rear wall wrapping film sheet 8 is smaller than the area of ​​the second rear wall wrapping film sheet 9. In the Mylar film folding type, the connection of the front wall wrapping film sheet and the connection of the rear wall wrapping film sheet are staggered, which can avoid the stress point of film tearing after the battery is heated and expanded.

[0027] The utility model also provides a battery, comprising a battery core and the Mylar film. The Mylar film is used to wrap the battery core. The Mylar film can save the traditional hot melt glue dispensing step, shorten the production time of the battery core, increase the bonding area, and increase the bonding strength.

[0028] Obviously, the above embodiments of the present invention are merely examples for the purpose of clearly illustrating the present invention, and are not intended to limit the implementation methods of the present invention. For those skilled in the art, various obvious changes, readjustments and substitutions can be made without departing from the scope of protection of the present invention. It is not necessary and impossible to list all implementation methods here. Any modifications, equivalent substitutions and improvements made within the spirit and principles of the present invention shall be included in the scope of protection of the claims of the present invention.

Claims

1. A Mylar film, comprising a side wall wrapping film sheet and a bottom wall wrapping film sheet for wrapping a battery cell, wherein the battery cell has a bottom wall and a top wall arranged opposite to each other, and a side enclosure arranged between the bottom wall and the top wall, wherein the side wall wrapping film sheet is used to fit the side enclosure, and the bottom wall wrapping film sheet is used to fit the bottom wall, characterized in that: The side wall wrapping membrane sheets are respectively arranged on both sides of the bottom wall wrapping membrane sheet and are connected to the side wall wrapping membrane sheets, a first adhesive layer is arranged on the side wall wrapping membrane sheet near the top wall, and a second adhesive layer is arranged at the connection between the side wall wrapping membrane sheet and another side wall wrapping membrane sheet, and a plurality of penetration holes are opened on the bottom wall wrapping membrane sheet.

2. The Mylar film according to claim 1, characterized in that: The side enclosure includes a front wall and a rear wall that are relatively arranged, and a left wall and a right wall that are relatively arranged; the side wall wrapping film includes a first front wall wrapping film sheet and a second front wall wrapping film sheet for fitting the front wall, a first rear wall wrapping film sheet and a second rear wall wrapping film sheet for fitting the rear wall, a left wall wrapping film sheet for fitting the left wall, and a right wall wrapping film sheet for fitting the right wall, and the left wall wrapping film sheet and the right wall wrapping film sheet are respectively connected to the bottom wall wrapping film sheet.

3. The Mylar film according to claim 2, characterized in that: The left wall wrapping film sheet is arranged between the first front wall wrapping film sheet and the first rear wall wrapping film sheet, and is respectively connected to the left wall wrapping film sheet; the right wall wrapping film sheet is arranged between the second front wall wrapping film sheet and the second rear wall wrapping film sheet, and is respectively connected to the right wall wrapping film sheet.

4. The Mylar film according to claim 3, characterized in that: A first folded edge is provided between the left wall wrapping film sheet and the first front wall wrapping film sheet and the first rear wall wrapping film sheet; a second folded edge is provided between the right wall wrapping film sheet and the second front wall wrapping film sheet and the second rear wall wrapping film sheet.

5. The Mylar film according to claim 4, characterized in that: The area of ​​the first front wall wrapping film sheet and the second front wall wrapping film sheet is larger than the area of ​​the second one; the area of ​​the first rear wall wrapping film sheet and the second rear wall wrapping film sheet is larger than the area of ​​the second one.

6. The Mylar film according to claim 5, characterized in that: A second adhesive layer is disposed on one of the first front wall wrapping film sheet and the second front wall wrapping film sheet; a second adhesive layer is disposed on one of the first rear wall wrapping film sheet and the second rear wall wrapping film sheet.

7. A battery, characterized in that: It comprises a battery core and the Mylar film as claimed in any one of claims 1 to 6, wherein the Mylar film is used for wrapping the battery core.

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