Battery insulating film and battery

Abstract

The utility model discloses a battery insulating film which comprises a Mylar film and a bottom supporting piece, the Mylar film comprises a side wall wrapping film and a bottom wall wrapping film connected with the side wall wrapping film, the Mylar film is 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, and the side wall is located between the bottom wall and the top wall; the side wall wrapping membrane is used for wrapping the side wall, and the bottom wall wrapping membrane is used for wrapping the bottom wall; edges extending out of the bottom wall wrapping membrane are arranged on the two sides of the bottom wall wrapping membrane respectively, grooves are formed by the edges and the bottom wall wrapping membrane, and the bottom supporting piece is arranged in the grooves and supports the bottom wall wrapping membrane. According to the utility model, the bottom support sheet groove is prepared in advance at the bottom of the Mylar film, and only the bottom support sheet needs to be placed in the groove to be fixed in the assembly process; the process complexity in the hot melting process is avoided, and meanwhile the risk that the bottom supporting piece falls off from the lower portion is avoided. And the bottom support sheet and the Mylar film are consistent in hole position, so that sufficient electrolyte infiltration is ensured.

Description

Technical Field

[0001] The utility model relates to the field of new energy, in particular to a battery insulating film 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 diaphragm of the bare core package from being scratched by the side of the aluminum shell during the shelling and later use. The bottom of the core package is more susceptible to greater impact due to factors such as vehicle bumps. In order to protect the bottom of the core package, a bottom support sheet is also provided. The bottom support sheet is used to support the core package to prevent the bottom of the aluminum shell from damaging the core package. In addition, the Mylar film and the bottom support sheet can also prevent the core package from direct contact with the aluminum shell to play a role in insulation protection. The materials of Mylar film and base plate are both PP, PC, PET, PVC insulating sheets, and the two are generally fixed together by hot-melt bonding, which has the following defects: on the one hand, the hot-melt process between Mylar film and base plate is relatively complicated, and the hot-melt process is affected by factors such as temperature, pressure and material. If the process parameters are not properly matched, Mylar film may easily over-melt and draw wires, Mylar film may hot-melt protrusions, and Mylar film may fall off due to insufficient hot-melt between the Mylar film and the base plate; on the other hand, the protrusions and wires after hot-melt can easily penetrate into the core package, causing the diaphragm to be punctured, the pole piece to lose powder, and other undesirable phenomena.

[0003] Patent application number 202321542189.8 uses the bottom support sheet and the concave hole at the bottom of the Mylar film to clamp. This method avoids the risk of hot melting, but the card slot is unstable and easy to fall off during shaking. Therefore, how to design a structure that can solve the above problem is an urgent problem to be solved. Utility Model Content

[0004] The purpose of the utility model is to provide an insulating film and a battery that solve the above problems.

[0005] To achieve the above purpose, the utility model provides the following technical solutions:

[0006] A battery insulating film, comprising a Mylar film and a bottom support sheet, wherein the Mylar film comprises a side wall wrapping film sheet and a bottom wall wrapping film sheet connected to the side wall wrapping film sheet, the Mylar film is used to wrap a battery cell, the battery cell has a bottom wall and a top wall arranged opposite to each other, and a side enclosure located between the bottom wall and the top wall; the side wall wrapping film sheet is used to wrap the side enclosure, and the bottom wall wrapping film sheet is used to wrap the bottom wall; edges extending from the bottom wall wrapping film sheet are respectively arranged on both sides of the bottom wall wrapping film sheet, the edges and the bottom wall wrapping film sheet form a groove, and the bottom support sheet is arranged in the groove and supports the bottom wall wrapping film sheet.

[0007] Preferably, the ends of the edge are bent toward the center of the groove to form a bent portion.

[0008] Preferably, the bottom supporting sheet is provided with a protrusion extending from the bottom supporting sheet, and the step portions on both sides of the protrusion cooperate with the bending portion to connect the bottom wall wrapping membrane sheet with the bottom supporting sheet.

[0009] Preferably, the bottom supporting piece is in a Wang shape, and the ends of the bottom supporting piece are respectively connected to the grooves.

[0010] Preferably, the side enclosure of the battery cell includes a front side wall and a rear side wall that are relatively arranged, and a left side wall and a right side wall that are relatively arranged, the side wall wrapping film wraps the front side wall wrapping film and the rear side wall wrapping film, the bottom wall wrapping film is located between the front side wall wrapping film and the rear side wall wrapping film, the front side wall wrapping film can be fitted with the front side wall, and the rear side wall wrapping film can be fitted with the rear side wall.

[0011] Preferably, the front side wall wrapping film sheet is provided with two first folded edge portions, and the rear side wall wrapping film sheet is provided with two second folded edge portions, wherein one of the first folded edge portions and one of the second folded edge portions are used to fit with the left side wall, and another of the first folded edge portions and another of the second folded edge portions are used to fit with the right side wall.

[0012] Preferably, a first fold line is provided between the front side wall wrapping film sheet and the two first folded edge portions; and / or a second fold line is provided between the rear side wall wrapping film sheet and the two second folded edge portions.

[0013] Preferably, the area of ​​the first folded edge portion is greater than the area of ​​the second folded edge portion.

[0014] Preferably, the bottom wall wrapping membrane sheet is provided with a first permeation hole, the bottom supporting sheet is provided with a second permeation hole, and the first permeation hole is directly opposite to the second permeation hole.

[0015] The utility model provides a battery, comprising a battery core and the above-mentioned battery insulation film, wherein the Mylar film of the battery insulation film is used for wrapping the battery core.

[0016] The beneficial effects of the utility model are as follows: the utility model prepares the bottom support sheet groove in advance at the bottom of the Mylar film, and during the assembly process, the bottom support sheet only needs to be placed in the groove and fixed; the complicated process of the hot melt process is avoided, and the risk of the bottom support sheet falling off from the bottom is avoided. The bottom support sheet is consistent with the hole position of the Mylar film, ensuring sufficient electrolyte infiltration. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] Figure 1 It is a structural schematic diagram of the utility model;

[0018] Figure 2 It is a schematic diagram of the structure of the Mylar film of the utility model;

[0019] Figure 3 It is a structural schematic diagram of the bottom support piece of the utility model;

[0020] Figure 4 It is a side view structural schematic diagram of the utility model;

[0021] Figure 5 It is a structural schematic diagram of the bottom wall wrapped membrane of the utility model;

[0022] Figure 6 It is a structural schematic diagram of the combination of the bottom support sheet and the bottom wall wrapping membrane sheet of the utility model;

[0023] In the figure, 1, Mylar film; 11, side wall wrapping film; 111, front side wall wrapping film; 112, rear side wall wrapping film; 113, first folding edge; 114, second folding edge; 115, first crease line; 116, second crease line; 12, bottom wall wrapping film; 121, first penetration hole; 2, bottom support sheet; 21, second penetration hole; 3, groove; 31, edge; 32, bending portion; 4, protrusion; 41, step portion. DETAILED DESCRIPTION

[0024] The technical solution of this patent is further described in detail below in conjunction with specific implementation methods.

[0025] 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.

[0026] 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.

[0027] 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.

[0028] 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.

[0029] like Figures 1 to 6 As shown, the battery insulation film includes a Mylar film 1 and a bottom support sheet 2, wherein the Mylar film 1 includes a side wall wrapping film sheet 11 and a bottom wall wrapping film sheet 12 connected to the side wall wrapping film sheet 11. The Mylar film 1 is used to wrap a battery cell, and the battery cell has a bottom wall and a top wall that are relatively arranged, and a side wall between the bottom wall and the top wall. The side wall wrapping film sheet 11 can wrap the side wall, and the bottom wall wrapping film sheet 12 can wrap the bottom wall, thereby completing the wrapping of the battery cell.

[0030] Furthermore, edges 31 extending out of the bottom wall wrapping film 12 are respectively arranged on both sides of the bottom wall wrapping film 12. The edges 31 and the bottom wall wrapping film 12 form a groove 3. Among them, the ends of the edges 31 are bent towards the center of the groove 3 to form bent portions 32. The bottom support piece 2 is arranged in the groove 3 and supports the bottom wall wrapping film 12. Inserting the bottom support piece into the groove 3 to quickly connect the bottom support piece 2 and the groove 3 can omit the hot melting process in the traditional solution, the installation process is simple, and it can avoid the safety hazards caused by over-melting wire drawing and non-melting between the Mylar film 1 and the bottom support piece 2 in the hot melting process. At the same time, placing the bottom support piece 2 inside the Mylar film 1 can avoid the risk of falling off caused by insufficient hot melting.

[0031] Furthermore, the bottom support piece 2 is provided with a protrusion 4 extending out of the bottom support piece 2. The stepped portions 41 on both sides of the protrusion 4 cooperate with the bent portions 32 to connect the bottom wall wrapping film 12 and the bottom support piece 2. The bottom support piece 2 of the present utility model is in a king shape. The six stepped portions 41 of the bottom support piece 2 are respectively stuck at the positions of the bent portions 32 of the groove 3. The bent portions 32 of the present utility model can be provided with 6 to cooperate with the stepped portions 41.

[0032] The width of the protrusion 4 of the present utility model is between 3 mm and 9 mm, specifically it can be 3 mm, 4 mm, 5 mm, 6 mm, 7 mm, 8 mm or 9 mm. In this embodiment, the designed width of the protrusion 4 is 7 mm; and the opening width of the groove 3 corresponding to the position of the protrusion 4 is also between 3 mm and 9 mm, specifically it can be 3 mm, 4 mm, 5 mm, 6 mm, 7 mm, 8 mm or 9 mm. In this embodiment, the opening width of the groove 3 corresponding to the position of the protrusion 4 is also 7 mm. The actual height of the protrusion 4 should be slightly greater than the actual height of the groove 3 during the processing to form an interference fit between the two, enhance the stability of the connection, and avoid loosening between the Mylar film 1 and the bottom support piece 2. Optionally, the height of the protrusion 4 is between 0.1 mm and 0.4 mm, specifically it can be 0.1 mm, 0.15 mm, 0.2 mm, 0.25 mm, 0.3 mm, 0.35 mm or 0.4 mm. In this embodiment, it is 0.25 mm. The depth of the groove 3 is between 1 mm and 7 mm, specifically it can be 1 mm, 2 mm, 3 mm, 4 mm, 5 mm, 6 mm or 7 mm. In this embodiment, it is 4 mm.

[0033] In the present embodiment, the battery cell is a square battery cell, and the side of the battery cell includes a front side wall and a rear side wall that are relatively arranged, and a left side wall and a right side wall that are relatively arranged; the side wall wrapping film 11 includes a front side wall wrapping film 111 and a rear side wall wrapping film 112, and the bottom wall wrapping film 12 is located between the front side wall wrapping film 111 and the rear side wall wrapping film 112, the front side wall wrapping film 111 can be fitted with the front side wall, and the rear side wall wrapping film 112 can be fitted with the rear side wall, so that the front and rear side walls of the battery cell are wrapped respectively by the front side wall wrapping film 111 and the rear side wall wrapping film 112.

[0034] The front side wall wrapping film 111 is provided with two first folded edge portions 113, and the rear side wall wrapping film 112 is provided with two second folded edge portions 114, wherein one of the first folded edge portions 113 and one of the second folded edge portions 114 are used to fit with the left side wall, and the other first folded edge portion 113 and the other second folded edge portion 114 are used to fit with the right side wall, thereby wrapping the left and right side walls of the battery cell respectively.

[0035] The assembly steps of the battery insulation film and the battery cell in this embodiment are as follows: first, the step portions 41 on both sides of the protrusion 4 are matched and connected with the bending portions by a structure such as a manipulator, so that the inner side of the bottom wall wrapping film sheet 12 of the Mylar film 1 is connected to the bottom support sheet 2. Then, the bottom wall wrapping film sheet 12 wraps the bottom wall of the battery cell, folds the front side wall wrapping film sheet 111 and the rear side wall wrapping film sheet 112, so that the front side wall wrapping film sheet 111 and the rear side wall wrapping film sheet 112 are respectively attached to the front and rear side walls of the battery cell, and then folds the first folding edge portion 113 and the second folding edge portion 114, so that one of the first folding edge portions 113 and one of the second folding edge portions 114 are used to fit with the left side wall, and the other first folding edge portion 113 and the other second folding edge portion 114 are used to fit with the right side wall. Optionally, the first folding edge portion 113 and the second folding edge portion 114 used to fit with the left side wall or the right side wall partially overlap.

[0036] A first crease line 115 is provided between the front side wall wrapping film 111 and the two first folding portions 113 ; and / or a second crease line 116 is provided between the rear side wall wrapping film 112 and the two second folding portions 114 , thereby indicating the folding positions of the first folding portions 113 and the second folding portions 114 .

[0037] The area of ​​the first folded edge portion 113 is larger than that of the second folded edge portion 114. The area of ​​one folded edge portion is larger than that of the other folded edge portion, and in use, the second folded edge portion 114 with a smaller area can be placed inside, and the first folded edge portion 113 with a larger area can be placed outside, or the second folded edge portion 114 with a smaller area can be placed outside, and the first folded edge portion 113 with a larger area can be placed inside.

[0038] Since the wider and thicker the battery core package is, the larger the battery capacity is, the more free electrolyte is required at the bottom of the core package. In this regard, the bottom wall wrapping film 12 is provided with a first permeable hole 121, and the bottom support sheet 2 is provided with a second permeable hole 21. The first permeable hole 121 is directly opposite to the second permeable hole 21, so that the electrolyte at the bottom of the core package can leak through the first permeable hole 121 and the second permeable hole 21.

[0039] The present embodiment also provides a battery, including a battery cell and the above-mentioned battery insulating film. The Mylar film 1 of the battery insulating film is used to wrap the battery cell. The battery insulating film can provide protection for the battery cell and can omit the hot melt process in the traditional solution. The installation process is simple and can avoid the safety hazards caused by over-melting and wire drawing between the Mylar film 1 and the bottom support sheet 2 and unmelting during the hot melt process.

[0040] 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 battery insulating film, comprising a Mylar film and a bottom support sheet, wherein the Mylar film comprises a side wall wrapping film sheet and a bottom wall wrapping film sheet connected to the side wall wrapping film sheet, the Mylar film is used to wrap a battery cell, the battery cell has a bottom wall and a top wall arranged opposite to each other, and a side wall located between the bottom wall and the top wall; the side wall wrapping film sheet is used to wrap the side wall, and the bottom wall wrapping film sheet is used to wrap the bottom wall; characterized in that: Edges extending out of the bottom wall wrapping film are respectively arranged on both sides of the bottom wall wrapping film. The edges and the bottom wall wrapping film form a groove, and the bottom support piece is arranged in the groove and supports the bottom wall wrapping film. The bottom support piece is in a king shape, and the end parts of the bottom support piece are respectively connected to the groove.

2. The battery insulating film according to claim 1, characterized in that: The end parts of the edges are bent towards the center of the groove to form bending parts.

3. The battery insulating film according to claim 2, characterized in that: The bottom support piece is provided with protrusions extending out of the bottom support piece, and the stepped parts on both sides of the protrusions cooperate with the bending parts so that the bottom wall wrapping film is connected to the bottom support piece.

4. The battery insulating film according to any one of claims 1 to 3, characterized in that: The side perimeter of the battery cell includes a front side wall and a rear side wall which are oppositely arranged, and a left side wall and a right side wall which are oppositely arranged. The side wall wrapping film wraps the front side wall wrapping film and the rear side wall wrapping film. The bottom wall wrapping film is located between the front side wall wrapping film and the rear side wall wrapping film. The front side wall wrapping film can be attached to the front side wall, and the rear side wall wrapping film can be attached to the rear side wall.

5. The battery insulating film according to claim 4, characterized in that: The front side wall wrapping film is provided with two first folding edge parts, and the rear side wall wrapping film is provided with two second folding edge parts. One of the first folding edge parts and one of the second folding edge parts are used for attaching to the left side wall, and the other first folding edge part and the other second folding edge part are used for attaching to the right side wall.

6. The battery insulating film according to claim 5, characterized in that: First crease lines are respectively arranged between the front side wall wrapping film and the two first folding edge parts; and / or, second crease lines are respectively arranged between the rear side wall wrapping film and the two second folding edge parts.

7. The battery insulating film according to claim 6, characterized in that: The area of the first folding edge part is larger than the area of the second folding edge part.

8. The battery insulating film according to claim 1, characterized in that: The bottom wall wrapping film is provided with a first penetration hole, and the bottom support piece is provided with a second penetration hole. The first penetration hole is aligned with the second penetration hole.

9. A battery, characterized in that: It includes a battery cell and the battery insulating film according to any one of claims 1-8. The Mylar film of the battery insulating film is used for wrapping the battery cell.

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