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CN-120613522-B - Battery unit, battery pack and insulation treatment method of battery unit

CN120613522BCN 120613522 BCN120613522 BCN 120613522BCN-120613522-B

Abstract

The application discloses a battery unit, a battery pack and an insulation treatment method of the battery unit, wherein the battery unit comprises a battery shell, a part of the outer surface of the battery shell is coated with a first insulation film, a shell mounting surface of the battery shell is provided with a second insulation film, the shell mounting surface is one side surface of the battery shell facing a bottom plate, the (S2×F2)/(S1×F1) is less than or equal to 54 and F2> F1 is less than or equal to 0.83, wherein S1 is the area of the first insulation film on the shell mounting surface, S2 is the area of the second insulation film on the shell mounting surface, F1 is the peeling strength of the first insulation film, and F2 is the peeling strength of the second insulation film. The application can ensure better bonding strength between the battery unit and the bottom plate and can also prevent the problem of low attachment yield of the insulating film on the basis of improving the insulation protection effect based on the relationship between the areas of the first insulating film and the second insulating film and the peeling strength.

Inventors

  • LI NING
  • XU JIULING
  • LI GUOWEI

Assignees

  • 中创新航科技集团股份有限公司

Dates

Publication Date
20260512
Application Date
20250610

Claims (20)

  1. 1. The battery unit is arranged on a bottom plate (200) and is characterized by comprising a battery shell (110), wherein a first insulating film (120) is coated on part of the outer surface of the battery shell (110), a second insulating film (130) is arranged on a shell mounting surface of the battery shell (110), the shell mounting surface is a surface of one side of the battery shell (110) facing the bottom plate (200), S2 xF 2)/(S1 xF 1) is less than or equal to 0.83 and less than or equal to 54, F1 is 0.2N/mm-0.9N/mm, F2 is 0.5N/mm-3N/mm, and F2> F1 and S2/S1 are selected from the range of 0.5-3.8; S1 is the area of the first insulating film (120) on the mounting surface of the shell, and the unit is mm 2 ; S2 is the area of the second insulating film (130) on the mounting surface of the shell, and the unit is mm 2 ; F1 is the peel strength of the first insulating film (120), in N/mm; F2 is the peel strength of the second insulating film (130), and the unit is N/mm.
  2. 2. The battery cell according to claim 1, wherein an area S1 of the first insulating film (120) on the housing mounting surface is 770mm 2 ~24225mm 2 ; the area S2 of the second insulating film (130) on the mounting surface of the shell is 380mm 2 ~96900 mm 2 .
  3. 3. The battery unit according to claim 1, wherein on the case mounting surface, an edge of at least one side of the second insulating film (130) is spaced from an edge of the corresponding side of the case mounting surface.
  4. 4. A battery unit according to claim 3, wherein on the housing mounting surface, edges of either side of the second insulating film (130) are spaced from edges of the corresponding side of the housing mounting surface.
  5. 5. The battery unit according to claim 1, wherein on the housing mounting surface, an edge of at least one side of the second insulating film (130) is flush with an edge of a corresponding side of the housing mounting surface.
  6. 6. The battery unit according to claim 5, wherein the second insulating film (130) covers the entire area of the housing mounting surface on the housing mounting surface.
  7. 7. The battery unit according to claim 1, wherein the case mounting surface is of a rectangular structure, and at least two relatively long sides are covered with the first insulating film (120).
  8. 8. The battery unit according to claim 7, wherein four sides of the housing mounting surface are each covered with the first insulating film (120).
  9. 9. The battery unit according to claim 1, wherein the first insulating film (120) is flush-butted with at least one side edge of the second insulating film (130) on the housing mounting surface.
  10. 10. The battery unit according to claim 9, wherein the first insulating film (120) is flush-butted with an edge of either side of the second insulating film (130) on the housing mounting surface.
  11. 11. The battery unit according to claim 1, wherein, on the case mounting surface, there is an overlap region of the first insulating film (120) and the second insulating film (130).
  12. 12. The battery cell of claim 11, wherein in the overlap region, the first insulating film (120) is located on a side of the second insulating film (130) facing away from the case mounting surface; Or alternatively In the overlapping region, the second insulating film (130) is located on a side of the first insulating film (120) facing away from the housing mounting surface.
  13. 13. The battery cell according to any one of claims 1 to 12, wherein the thickness of the first insulating film (120) is 80 μm to 250 μm; And/or the number of the groups of groups, The thickness of the second insulating film (130) is 80-250 [ mu ] m.
  14. 14. The battery cell according to any one of claims 1 to 12, wherein the first insulating film (120) is made of polyethylene terephthalate, polyimide, polypropylene or acryl glue; And/or the number of the groups of groups, The second insulating film (130) is made of polyethylene terephthalate, polyimide, polypropylene or acrylic adhesive.
  15. 15. The battery unit according to any one of claims 1 to 12, wherein an insulating region composed of the first insulating film (120) and the second insulating film (130) covers the entire region of the housing mounting surface.
  16. 16. The battery cell according to any one of claims 1 to 12, wherein the hardness of the battery case (110) is HB20 to HB110.
  17. 17. The battery cell according to any one of claims 1 to 12, wherein the battery case (110) is a steel case, 15≤s2×f2)/(s1×f1). Ltoreq.50.
  18. 18. The battery cell according to any one of claims 1 to 12, wherein the battery case (110) is an aluminum case, and 0.83≤s2×f2)/(s1×f1≤25.
  19. 19. The battery cell of any one of claims 1-12, wherein a post assembly is disposed on the battery housing, and wherein a surface of the battery housing on which the post assembly is disposed is a housing electrical contact surface; The housing electrical connection surface and the housing mounting surface are two surfaces of the battery housing that are oppositely arranged; Or alternatively The shell power connection surface and the shell mounting surface are two surfaces connected with the battery shell; Or alternatively The housing electrical connection surface and the housing mounting surface are the same surface of the battery housing.
  20. 20. The battery unit according to any one of claims 1 to 12, wherein an explosion-proof valve is provided on the battery case, and a surface of the battery case on which the explosion-proof valve is provided is a case pressure release surface; the housing pressure relief surface and the housing mounting surface are two surfaces of the battery housing that are oppositely arranged; Or alternatively The shell pressure release surface and the shell mounting surface are two surfaces connected with the battery shell; Or alternatively The housing relief surface and the housing mounting surface are the same surface of the battery housing.

Description

Battery unit, battery pack and insulation treatment method of battery unit Technical Field The application relates to the technical field of battery packs, in particular to a battery unit, a battery pack and an insulation treatment method of the battery unit. Background The battery unit generally comprises a battery shell and an electric core arranged in the battery shell, wherein the electric core is a core part of the battery unit and consists of a positive plate, a negative plate, a diaphragm and electrolyte. The battery shell is the outermost protection structure of the battery unit and plays a role in accommodating and protecting the internal components. In order to ensure that the battery unit can safely and stably run, an insulating film is generally required to be stuck to the outer side of the battery shell, the electrode of the battery unit can have high voltage in the charge and discharge process, the insulating film can effectively prevent current conduction between the battery shell and an external conductor, short circuit is prevented, and serious safety problems such as battery performance reduction, overheat and even fire explosion are avoided. The battery unit is usually adhered to the bottom plate in an adhesive manner, an insulating film is adhered to one side of the battery unit facing the bottom plate, the insulating film does not completely cover one side surface of the battery unit facing the bottom plate, and a part of exposed area (called an insulating film windowing area) is reserved. Therefore, how to prevent the problem of low attachment yield due to repair difficulty while ensuring the adhesive strength between the battery unit and the bottom plate is a problem to be solved by those skilled in the art. Disclosure of Invention Accordingly, an object of the present application is to provide a battery unit, which can prevent the problem of low attachment yield due to difficult repair while ensuring the adhesion strength between the battery unit and the bottom plate; Another object of the present application is to provide a battery pack having the above battery cell, and an insulation treatment method of the above battery cell. In order to achieve the above purpose, the present application provides the following technical solutions: The first aspect of the application provides a battery unit for being arranged on a bottom plate, comprising a battery shell, wherein a part of the outer surface of the battery shell is coated with a first insulating film, a shell mounting surface of the battery shell is provided with a second insulating film, the shell mounting surface is the surface of one side of the battery shell facing the bottom plate, and the (S2×F2)/(S1×F1) is less than or equal to 54 and less than or equal to 0.83, and F2 is more than or equal to F1; S1 is the area of the first insulating film on the mounting surface of the shell, and the unit is mm 2; s2 is the area of the second insulating film on the mounting surface of the shell, and the unit is mm 2; f1 is the peeling strength of the first insulating film, and the unit is N/mm; F2 is the peel strength of the second insulating film in N/mm. In the battery unit provided by the application, the second insulating film is added on the mounting surface of the battery shell facing the bottom plate. The arrangement is such that the housing mounting surface facing the bottom plate includes both the first insulating film and the second insulating film, i.e., the partial region not covered by the first insulating film can be covered by the second insulating film, so as to prevent the problem of poor insulating performance caused by the large-area exposure of the region not covered by the first insulating film. The battery unit disclosed by the application has the advantages that (S2×F2)/(S1×F1) is less than or equal to 0.83 and less than or equal to (S2×F2)/(S1×F1) and less than or equal to 54, the problems that the bonding strength between a battery shell and a bottom plate is weak and the vibration failure risk is high due to the fact that the value of the relational expression is too small can be avoided, and the problems that the repair of a second insulating film is difficult and the yield of a coated second insulating film is low due to the fact that the value of the relational expression is too large can be avoided. The application can ensure better bonding strength between the battery unit and the bottom plate on the basis of improving the insulation protection effect based on the relation between the areas of the first insulation film and the second insulation film and the peeling strength, and can also prevent the problem of low attaching yield of the second insulation film caused by difficult repair. A second aspect of the present application provides a battery pack comprising a base plate and a battery cell provided on the base plate, the battery cell being a battery cell as described above. The battery pack provided by th