Annular outer wrapping film, battery and module

Abstract

The annular outer wrapping film comprises a first side face, a second side face, a third side face and a fourth side face which are connected end to end to form an annular structure. The top edges of the second side face and the fourth side face are bent inwards and extend, and after extending, a first windowing area is formed on the top face. The bottom edges of the first side face, the second side face, the third side face and the fourth side face are bent inwards and extend, and after extending, a second windowing area is formed on the bottom face. The utility model further comprises a battery and a module. The beneficial effects of the utility model are that the first windowing area and the second windowing area can enable the aluminum shell to be directly bonded with other parts through the structural adhesive, thereby guaranteeing the bonding strength and the bonding stability, enabling the aluminum shell not to be loosened easily, guaranteeing the later module size, and enabling the aluminum shell to enter a box conveniently.

Description

Technical Field

[0001] This utility model relates to the field of power batteries, and more particularly to an annular outer coating. Background Technology

[0002] With the increasing maturity of lithium-ion battery technology, lithium-ion batteries are widely used as power batteries in electric vehicles and energy storage, and the requirements for the performance and safety of lithium-ion batteries are becoming increasingly stringent.

[0003] like Figure 1-1 , Figure 1-2 As shown, the main structure of battery 3 currently includes: cover plate 21' (integrating terminals, explosion-proof valve, upper plastic, lower plastic, and injection hole), connecting piece 23, electrode assembly 24, aluminum shell 22', blue film 25', and top cover patch 26'. The cover plate 21' and aluminum shell 22' are laser-welded to form a sealed space with sufficient mechanical strength to protect the electrode assembly 24. The bare cell insulating sheet and the lower plastic of cover plate 21' are hot-melted and wrapped around the outside of the electrode assembly. The lower plastic of cover plate 21' presses down on the separator of electrode assembly 24, thus securing the electrode assembly 24 well within the shell and preventing internal short circuits caused by electrode assembly movement. The blue film 25' covers the outer surface of the aluminum shell 22', and the top cover patch 26' covers the surface of the smooth aluminum plate of cover plate 21', thereby ensuring the insulation performance of the cell.

[0004] Coating the battery cells with a blue release film is a crucial step in the production of power batteries. This blue film, also known as a separator, anti-stick film, or protective film, comes in various colors including red, green, blue, white, and black. It is available in single-sided and double-sided release films, with blue film being the most commonly used in power batteries. As an insulating material, the blue film separates the battery cells, preventing the impact of various faults in one cell on other cells.

[0005] Traditional batteries have a blue film covering the aluminum casing, with the top cover patch adhered to the smooth aluminum plate surface of the cover. During module assembly, structural adhesive needs to be applied directly to the side of the cell using epoxy board. This reduces the bonding strength between the cell and other components, making the bond less secure and increasing the likelihood of loosening. This can also result in an oversized module, making it more difficult or impossible to fit the entire module into the enclosure, which is detrimental to the requirements of new technologies such as CTP (cell-to-pack) and CTC (cell-to-chassis-and-underbody integration). Alternatively, during bonding, the battery window portion needs to be manually peeled off, increasing the assembly process and leading to low assembly efficiency.

[0006] The information disclosed in this background section is intended only to enhance the understanding of the overall background of this utility model and should not be construed as an admission or in any way implying that the information constitutes prior art known to those skilled in the art. Utility Model Content

[0007] The technical problem to be solved by this utility model is: how to solve the problem in the prior art that the presence of the blue film on the battery leads to low bonding strength between the battery cell and other structural components, making them easy to loosen, resulting in a larger overall module size, greater assembly difficulty, and lower efficiency.

[0008] This utility model solves the above-mentioned technical problems through the following technical means:

[0009] The annular outer membrane includes a first side, a second side, a third side, and a fourth side that are joined end to end to form an annular structure; the top edges of the second and fourth sides are bent inward and extended, forming a first window area on the top surface after extension; the bottom edges of the first, second, third, and fourth sides are bent inward and extended, forming a second window area on the bottom surface after extension.

[0010] The first and second window areas in this invention allow the aluminum shell to be directly bonded to other components using structural adhesive, ensuring bonding strength and stability, preventing loosening, guaranteeing the module dimensions later, and facilitating box assembly.

[0011] Preferably, the overlapping area is formed at the beginning and end of the annular outer film, and the width of the overlapping area is C, where 5≤C≤10mm.

[0012] Preferably, the top edge of the second side is bent inward to form the first folded edge, and the top edge of the fourth side is bent inward to form the second folded edge. The width of both the first folded edge and the second folded edge is A, where 5mm≤A≤8mm.

[0013] Preferably, the bottom edge of the second side is bent inward to form the third fold, and the bottom edge of the fourth side is bent inward to form the fourth fold. The width of both the third and fourth folds is D, where 4mm ≤ D ≤ 8mm.

[0014] Preferably, the bottom edge of the first side is bent inward to form the fifth fold, and the bottom edge of the third side is bent inward to form the sixth fold. The width of both the fifth and sixth folds is E, where 4mm ≤ E ≤ 8mm.

[0015] Preferably, the first, second, third, and fourth sides, which are connected end to end, form a rectangular cavity structure.

[0016] Preferably, the first window area is a rectangular blank area, and the second window area is a rectangular blank area.

[0017] This invention reserves a first window area and a second window area during the process of wrapping the battery cell with an annular outer film. This eliminates the need to manually tear open the window portion when applying structural adhesive later, saving process steps and avoiding irregular window areas caused by manual tearing. The reserved first and second window areas in this invention have regular shapes, which facilitates adhesive application and ensures good adhesive consistency.

[0018] This utility model also discloses a battery, including an annular outer film and a battery cell. The annular outer film wraps around the outside of the battery cell. A first window area is located on the top surface of the battery cell, and a second window area is located on the bottom surface of the battery cell.

[0019] The battery in this invention can be bonded together by applying structural adhesive to the first and second window areas. This facilitates installation or cooling, improves bonding strength, effectively enhances the module's modality, facilitates installation into the casing, and increases the strength and rigidity of the battery structure, making it more resistant to vibration and impact, thereby enhancing the battery's reliability and safety.

[0020] Preferably, the top edges of the first and third sides are flush with the top surface of the cover plate of the battery cell, and the distance between the first side and one end of the top cover patch and the distance between the third side and the other end of the top cover patch are both B, 5mm≤B≤10mm.

[0021] This utility model also discloses a module, which includes multiple batteries arranged side by side.

[0022] The advantages of this utility model are:

[0023] (1) The first and second window opening areas in this utility model enable the aluminum shell to be directly bonded to other components through structural adhesive, ensuring bonding strength and bonding stability, preventing loosening, ensuring the module size in the later stage, and facilitating boxing.

[0024] (2) In the process of wrapping the battery cell with an annular outer film, the present invention reserves a first window area and a second window area, which eliminates the need to manually tear open the window part when applying structural adhesive later, saving process flow and avoiding irregular window area caused by manual tearing. The first window area and the second window area reserved in the present invention have regular shape, which facilitates adhesive application and ensures good adhesive consistency.

[0025] (3) The battery in this utility model can be bonded by applying structural adhesive to the first window area and the second window area. On the one hand, it is convenient for installation or cooling treatment. On the other hand, it can improve the bonding strength and effectively improve the mode of the module, making it easier to put into the box, improving the strength and rigidity of the battery structure, making it more resistant to vibration and impact, thereby enhancing the reliability and safety of the battery. Attached Figure Description

[0026] Figure 1-1 This is a schematic diagram of a battery explosion in the background art;

[0027] Figure 1-2 This is a three-dimensional structural diagram of a battery in the background technology;

[0028] Figure 2 This is a perspective view of the annular outer film of an embodiment of this utility model;

[0029] Figure 3 This is a top view of the annular outer film of this utility model embodiment;

[0030] Figure 4 This is a bottom view of the annular outer film of an embodiment of this utility model;

[0031] Figure 5 This is a perspective view of the battery cell according to an embodiment of the present invention;

[0032] Figure 6 This is a perspective view of a battery cell covered with an annular outer film according to an embodiment of the present invention;

[0033] Figure 7 This is a top view of the battery cell covered by the annular outer film according to an embodiment of the present invention;

[0034] Figure 8 This is a bottom view of the battery cell covered with an annular outer film according to an embodiment of the present invention;

[0035] Figure 9 This is a left view of the battery cell covered by the annular outer film according to an embodiment of the present invention;

[0036] Figure 10 This is a right view of the battery cell covered with an annular outer film according to an embodiment of the present invention;

[0037] Figure 11 This is a schematic diagram of the operation of the annular outer film covering the battery cell according to this utility model;

[0038] Figure 12 This is a schematic diagram of the operation of the annular outer film covering the battery cell according to this utility model. Figure 2 ;

[0039] Figure 13 This is a schematic diagram of the operation of the annular outer film covering the battery cell according to this utility model. Figure 3 ;

[0040] Figure 14 This is a schematic diagram of the operation of the annular outer film covering the battery cell according to this utility model. Figure 4 ;

[0041] Numbering on the map:

[0042] In the background technology: 3, battery; 21', cover plate; 23, connecting piece; 24, electrode assembly; 22', aluminum shell; 25', blue film; 26', top cover patch;

[0043] In this application: 1. Annular outer film; 11. First side surface; 111. Fifth folded edge; 12. Second side surface; 121. First folded edge; 122. Third folded edge; 13. Third side surface; 131. Overlapping area; 132. Sixth folded edge; 14. Fourth side surface; 141. Second folded edge; 142. Fourth folded edge; 15. First window area; 16. Second window area;

[0044] 2. Battery cell; 21. Cover plate; 22. Aluminum shell; 25. Blue film; 251. Middle slot; 252. Both end slots; 26. Top cover patch. Detailed Implementation

[0045] To make the objectives, technical solutions, and advantages of the embodiments of this utility model clearer, the technical solutions of the embodiments of this utility model will be clearly and completely described below in conjunction with the embodiments of this utility model. Obviously, the described embodiments are only some embodiments of this utility model, not all embodiments. Based on the embodiments of this utility model, all other embodiments obtained by those skilled in the art without creative effort are within the protection scope of this utility model.

[0046] Example 1:

[0047] Currently, see Figure 1-1 As shown, the blue film 25 covers the surface of the battery cell 2 to insulate and protect it. However, when the adhesive used to bond the battery cell 2 comes into direct contact with the outer film, the bonding strength decreases, the size increases, and the assembly becomes more difficult. Therefore, this embodiment provides an annular outer film 1, and two window areas are provided on the annular outer film 1.

[0048] like Figure 2 As shown, specifically, the annular outer membrane 1 includes a first side 11, a second side 12, a third side 13, and a fourth side 14 that connect end to end to form an annular structure. The annular outer membrane 1 is generally a rectangular cavity structure, with the first side 11 and the third side 13 facing each other, and the second side 12 and the fourth side 14 arranged opposite each other. In this embodiment, the first side 11 and the third side 13 are smaller faces, and the second side 12 and the fourth side 14 are larger faces. The adjacent corners of the first side 11, the second side 12, the third side 13, and the fourth side 14 form an arc-shaped transition.

[0049] It should be noted that, based on the current design of square batteries, if the square battery is deformed in size, the first side 11, the second side 12, the third side 13, and the fourth side 14 will also be deformed in size randomly, so as to be able to fit the battery in a practical way.

[0050] like Figure 2 , Figure 3As shown, the top edges of the second side 12 and the fourth side 14 bend inward and extend, forming a first window area 15 on the top surface. The first window area 15 is roughly a rectangular blank area. Figure 2 , Figure 4 As shown, the bottom edges of the first side 11, the second side 12, the third side 13, and the fourth side 14 are bent inward and extended, forming a second window area 16 on the bottom surface after extension. The second window area 16 is roughly a rectangular blank area.

[0051] In this embodiment, "inward" refers to the center of the annular outer film 1. The windowed area refers to the area without the blue film 25. Specifically, the bottom edges of the first side 11, the second side 12, the third side 13, and the fourth side 14 are all bent inward, forming folded areas at the corners; if the folded areas are not needed, part of the blue film 25 can be cut off before bending.

[0052] In this embodiment, the window area allows the aluminum shell 22 to be directly bonded to other components using structural adhesive, ensuring bonding strength and stability, preventing loosening, ensuring the module size in the later stage, and facilitating box placement.

[0053] Example 2:

[0054] like Figure 5 As shown, this embodiment discloses a battery, including the annular outer film 1 and the battery cell 2 in the above embodiment 1, wherein the annular outer film 1 wraps around the outside of the battery cell 2.

[0055] In this embodiment, the battery cell 2 is a square battery cell. The battery cell 2 includes a cover plate 21 and an aluminum shell 22. The cover plate 21 is welded to the top surface of the aluminum shell 22. The side surface of the aluminum shell 22 includes two small side surfaces and two large side surfaces.

[0056] It should be noted that other structural components of cell 2 (such as connecting pieces) can be connected in accordance with the cell structure in the background art. This embodiment does not involve other components, so they will not be described in detail.

[0057] like Figure 6 As shown, the annular outer film 1 wraps around the outer surface of the cell 2, and the first window area 15 is located on the top surface of the cell 2, as shown. Figure 8 As shown, the second window area 16 is located on the bottom surface of the battery cell 2. The first side 11 and the third side 13 cover the small side of the aluminum shell 22, and the second side 12 and the fourth side 14 cover the large side of the aluminum shell 22.

[0058] refer to Figure 3 , Figure 7As shown, the top edge of the second side 12 is bent inward to form the first folded edge 121, and the top edge of the fourth side 14 is bent inward to form the second folded edge 141. The width of the first folded edge 121 and the second folded edge 141 is A, where 5mm ≤ A ≤ 8mm. The top edges of the first side 11 and the third side 13 are basically flush with the top surface of the cover plate 21 (the cover plate 21 is recessed and installed, and the top surface of the cover plate 21 is flush with the top surface of the aluminum shell 22), with an allowable error of 1-3mm. The distance between the first side 11 and the top cover patch 26, and the distance between the third side 13 and the top cover patch 26, are both B, where 5mm ≤ B ≤ 10mm. The size of the top cover patch 26 is slightly smaller than that of the top cover 21, typically differing by 1-3mm on one side.

[0059] refer to Figure 4 , Figure 8 As shown, the bottom edge of the second side 12 is bent inward to form the third fold 122, and the bottom edge of the fourth side 14 is bent inward to form the fourth fold 142. The width of both the third fold 122 and the fourth fold 142 is D, where 4mm≤D≤8mm; the bottom edge of the first side 11 is bent inward to form the fifth fold 111, and the bottom edge of the third side 13 is bent inward to form the sixth fold 132. The width of both the fifth fold 111 and the sixth fold 132 is E, where 4mm≤E≤8mm.

[0060] like Figure 2 or Figure 9 As shown, the third side 13 includes an overlapping region 131, which is formed by overlapping the ends. The overlapping region 131 is approximately rectangular, extending from the top edge to the bottom edge of the third side 13. The width of the overlapping region 131 on the third side 13 is C, where 5 ≤ C ≤ 10 mm.

[0061] The process of the annular outer film 1 covering the battery cell 2 in this embodiment:

[0062] like Figure 11 As shown, the first step is to cut the blue film 25. The blue film 25 has a rectangular structure. The length of the blue film 25 is 5-10mm greater than the perimeter of the battery cell 2, and the width of the blue film 25 is 9-16mm greater than the height of the battery cell 2. A slot 251 is opened at the middle position of the top edge and at both ends. The width of the middle slot 251 is equal to the thickness of the battery cell 2, and the depth of the middle slot 251 is 5-8mm. The slots 252 at both ends are symmetrically arranged, and the width of the slots 252 at both ends is approximately 2 / 3 of the thickness of the battery cell 2. The second step is as follows... Figure 12 As shown, the middle part of the blue film 25 is attached to the small side of the battery cell 2, keeping the vertical symmetry line of the blue film 25 basically coincident with the vertical symmetry line of the first side 11. Figure 13 As shown, bend both ends of the blue film 25 towards the second side 12 and the fourth side 14 and attach them to the large side of the battery cell 2. The third step, as... Figure 14As shown, the two ends of the blue film 25 are connected to the other small side of the battery cell 2 and adhered to the battery cell 2, creating an overlapping area 131. Fourth step, refer to... Figure 7 As shown, one end of the first side 11, the second side 12, the third side 13, and the fourth side 14 are bent toward the bottom surface of the battery cell 2 and attached to the bottom surface of the battery cell 2, forming a second window area 16 in the central region; Reference Figure 8 As shown, in the fifth step, the other ends of the second side 12 and the fourth side 14 are bent toward the top surface of the battery cell 2 and attached to the top surface of the battery cell 2, forming a first window area 15 in the central area.

[0063] Figure 13 , Figure 14 The line drawn at the midpoint represents a crease. The blue film 25 can be applied to the surface of the cell 2 using existing technological processes (such as heating).

[0064] In this embodiment, during the process of wrapping the annular outer film 1 around the battery cell 2, a first window area 15 and a second window area 16 are reserved. This eliminates the need to manually tear open the window portion during subsequent application of structural adhesive, saving process steps and avoiding irregular window areas caused by manual tearing. Irregular windows can lead to inconsistent battery connection reliability within the same module. In this embodiment, the reserved first window area 15 and second window area 16 have regular shapes, which facilitates adhesive application, ensures good adhesive consistency, and maintains consistent connection reliability.

[0065] Example 3:

[0066] This embodiment discloses a module including the batteries described in the above-mentioned embodiments. Multiple batteries are arranged side-by-side. During assembly, the top first window area 15 of each battery is coated with structural adhesive and then connected to an epoxy board. The epoxy board is then fixed to a crossbeam using steel straps, thus connecting multiple batteries. The bottom second window area 16 of each battery is coated with structural adhesive and then bonded with a cold plate. The cold plate is used to cool the module. The cold plate is in direct contact with the battery cell 2, which improves both the bonding strength and the module's modal characteristics, facilitating installation in a battery case and enhancing the strength and rigidity of the battery structure. This makes the battery more resistant to vibration and impact, thereby improving its reliability and safety.

[0067] The module in this embodiment includes, but is not limited to, battery modules, battery packs, and battery systems. The actual application form of the module provided in this application embodiment can be, but is not limited to, the listed products, or other application forms. This application embodiment does not strictly limit the application form of the module, nor does it strictly limit the number of batteries or the connection method; it can be applied to current modules.

[0068] The above embodiments are only used to illustrate the technical solutions of this utility model, and are not intended to limit it. Although this utility model has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that modifications can still be made to the technical solutions described in the foregoing embodiments, or equivalent substitutions can be made to some of the technical features. Such modifications or substitutions do not cause the essence of the corresponding technical solutions to deviate from the spirit and scope of the technical solutions of the embodiments of this utility model.

Claims

1. An annular outer film, characterized in that, It includes a first side, a second side, a third side, and a fourth side that are connected end to end to form a ring structure; the top edges of the second and fourth sides are bent inward and extended, forming a first window area on the top surface; the bottom edges of the first, second, third, and fourth sides are bent inward and extended, forming a second window area on the bottom surface.

2. The annular outer film according to claim 1, characterized in that, The overlapping area formed at the beginning and end of the annular outer film has a width of C, where 5 ≤ C ≤ 10 mm.

3. The annular outer film according to claim 1, characterized in that, The top edge of the second side is bent inward to form the first fold, and the top edge of the fourth side is bent inward to form the second fold. The width of both the first and second folds is A, where 5mm ≤ A ≤ 8mm.

4. The annular outer film according to claim 1, characterized in that, The bottom edge of the second side is bent inward to form the third fold, and the bottom edge of the fourth side is bent inward to form the fourth fold. The width of both the third and fourth folds is D, where 4mm ≤ D ≤ 8mm.

5. The annular outer film according to claim 1, characterized in that, The bottom edge of the first side is bent inward to form the fifth fold, and the bottom edge of the third side is bent inward to form the sixth fold. The width of both the fifth and sixth folds is E, where 4mm ≤ E ≤ 8mm.

6. The annular outer film according to claim 1, characterized in that, The first, second, third, and fourth sides, which are connected end to end, form a rectangular cavity structure.

7. The annular outer film according to claim 1, characterized in that, The first window area is a rectangular blank area, and the second window area is a rectangular blank area.

8. A battery, characterized in that, The battery cell includes any one of the annular outer film and battery cell of claims 1-7, wherein the annular outer film is wrapped around the outside of the battery cell, the first window area is located on the top surface of the battery cell, and the second window area is located on the bottom surface of the battery cell.

9. The battery according to claim 8, characterized in that, The top edges of the first and third sides are flush with the top surface of the cell cover plate. The distance between the first side and one end of the top cover patch and the distance between the third side and the other end of the top cover patch are both B, where 5mm≤B≤10mm.

10. A module, characterized in that, It includes the plurality of batteries as described in claim 9 above, and the plurality of batteries are arranged side by side.

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