Search

CN-122013271-A - Preparation method of current collector, battery and battery processing equipment

CN122013271ACN 122013271 ACN122013271 ACN 122013271ACN-122013271-A

Abstract

The application relates to a preparation method of a current collector, the current collector, a battery and battery processing equipment. The preparation method of the current collector comprises the steps of unreeling a base foil, plating a plurality of metal layers on the surface of the base foil in the unreeling process to form a plurality of metal foils on the surface of the base foil, stripping the plurality of metal foils from the base foil, and cutting the stripped plurality of metal foils to obtain the current collector. In the processing process, the base foil is used as a temporary substrate for plating each metal layer, and the base foil forming the multilayer metal foil does not need to be additionally processed, so that the problem of belt breakage easily caused by independent preparation of the base foil is avoided. Therefore, the metal layer originally used as the base foil can be made thinner, for example, less than 4 μm, and the metal layer other than the base foil can be made thinner. By adopting the preparation method, the current collector with the thickness as low as 4 mu m can be processed, and the bottleneck that the current collector is difficult to be made to have the thickness below 5 mu m in the industry is broken through.

Inventors

  • CAI QIGUO
  • SUN XIN
  • LIU XIN
  • Li Huaimang
  • LIU HUANJI
  • LI CHENG

Assignees

  • 宁德时代新能源科技股份有限公司

Dates

Publication Date
20260512
Application Date
20241111

Claims (18)

  1. 1. The preparation method of the current collector is characterized by comprising the following steps of: Unreeling a base foil, wherein a plurality of metal layers are plated on the surface of the base foil in the unreeling process so as to form a plurality of metal foils on the surface of the base foil; Stripping the multilayer metal foil from the base foil; and cutting the stripped multilayer metal foil to obtain the current collector.
  2. 2. The method for preparing a current collector according to claim 1, wherein a plurality of metal layers are plated on the surface of the base foil during unreeling of the base foil to form a composite plating layer on the surface of the base foil, further comprising the steps of: And oxidizing the surface of the substrate foil to generate a metal oxide layer.
  3. 3. The method of manufacturing a current collector according to claim 1, wherein the step of plating a plurality of metal layers on the surface of the base foil during unreeling the base foil to form a plurality of metal foils on the surface of the base foil is preceded by the step of: An insulating layer is provided on one surface of the base foil, the other surface of the base foil remaining electrically conductive.
  4. 4. The method of manufacturing a current collector according to claim 1, wherein the step of unreeling a base foil, wherein a plurality of metal layers are plated on the surface of the base foil during unreeling to form a plurality of metal foils on the surface of the base foil, further comprises the step of: both surfaces of the base foil are kept conductive.
  5. 5. The method of manufacturing a current collector according to claim 1, wherein the thickness of the base foil is set in a range of 4 μm to 20 μm.
  6. 6. The method of manufacturing a current collector according to claim 5, wherein the thickness of the base foil is set in the range of 5 μm to 15 μm.
  7. 7. The method of manufacturing a current collector according to claim 1, wherein the base foil is configured as a stainless steel foil, a titanium foil, a nickel-chromium foil, or a nickel foil.
  8. 8. The method for manufacturing a current collector according to claim 1, wherein in the step of forming a multi-layered metal foil on the surface of the base foil by plating a multi-layered metal layer on the surface of the base foil during unreeling the base foil, specifically comprising: And sequentially and continuously plating a plurality of metal layers on the base foil, and rolling after plating all the metal layers.
  9. 9. The method of manufacturing a current collector according to any one of claims 1 to 8, further comprising, after the step of peeling the multilayer metal foil from the base foil, the step of: and performing antioxidation treatment on the stripped multilayer metal foil.
  10. 10. The method for manufacturing a current collector according to claim 9, further comprising, after the step of performing an antioxidation treatment on the peeled multilayer metal foil, the step of: and drying the multi-layer metal foil after the oxidation resisting treatment.
  11. 11. The method of manufacturing a current collector according to claim 9, further comprising, after the step of peeling the multilayer metal foil from the base foil, the step of: And rolling the peeled multi-layer metal foil into a roll.
  12. 12. The method of manufacturing a current collector according to any one of claims 1 to 8, further comprising, after the step of peeling the multilayer metal foil from the base foil, the step of: and rolling the substrate foil.
  13. 13. A current collector processed by the method for preparing a current collector according to any one of claims 1 to 12, wherein the current collector comprises a plurality of metal layers which are sequentially laminated, and the total thickness of the metal layers is less than or equal to 5 μm.
  14. 14. The current collector of claim 13, wherein the thickness of the largest metal layer among the plurality of metal layers is 4 μm or less.
  15. 15. A battery comprising a current collector according to claim 13 or 14.
  16. 16. A battery processing apparatus for processing a current collector using the method for producing a current collector according to any one of claims 1 to 12, comprising an electroplating device for continuously plating a plurality of the metal layers on the base foil, and a peeling device for peeling the plurality of the metal layers from the base foil.
  17. 17. The battery processing apparatus of claim 16, wherein the electroplating device comprises: the electroplating baths are sequentially connected in series and are used for accommodating the plating solution.
  18. 18. The battery processing apparatus according to claim 16, wherein the peeling means includes: At least one peeling roller around which the base foil coated with the multilayer metal foil passes; and the at least two winding rollers are used for respectively winding the substrate foil and the multilayer metal foil output from the stripping roller.

Description

Preparation method of current collector, battery and battery processing equipment Technical Field The application relates to the technical field of batteries, in particular to a preparation method of a current collector, the current collector, a battery and battery processing equipment. Background The current collector is used as a carrier of positive and negative active substances of the battery cell and plays a role in electron transmission, and is an important component of the battery cell, and the density and the thickness of the current collector directly influence the energy density of the battery cell. The current collector typically employs copper foil as the base foil, and further metal layers are plated on the base foil. In the traditional current collector preparation process, the base foil is usually processed and generated on a foil producing machine, and is limited by the preparation process of the foil producing machine, and the problem of belt breakage easily occurs when the base foil is too thin, so that the thickness of the finished product of the processed base foil is larger, and the overall thickness of the current collector with two layers and more structures is thicker. Disclosure of Invention Based on the above, it is necessary to provide a method for manufacturing a current collector, a battery and a battery processing device, which solve the problem that the base foil is easy to break during the current collector processing process, so as to process an ultra-thin current collector. In a first aspect, the present application provides a method for preparing a current collector, the method comprising: Unreeling the base foil, wherein a plurality of metal layers are plated on the surface of the base foil in the unreeling process so as to form a plurality of metal foils on the surface of the base foil; peeling the multilayer metal foil from the base foil; and cutting the stripped multilayer metal foil to obtain the current collector. The current collector is manufactured by sequentially plating each metal layer on the base foil, then stripping the multilayer metal layers from the base foil as a whole to obtain the required multilayer metal foil, and cutting the multilayer metal foil. In the processing process, the base foil is used as a temporary substrate for plating each metal layer, and the base foil forming the multilayer metal foil does not need to be additionally processed, so that the problem of belt breakage easily caused by independent preparation of the base foil is avoided. In one embodiment, before the step of unreeling the base foil, plating a plurality of metal layers on the surface of the base foil during unreeling to form a composite plating layer on the surface of the base foil, the method further comprises the steps of: And (3) oxidizing the surface of the substrate foil to generate a metal oxide layer. The metal oxide layer is formed by oxidizing the surface of the base foil to improve the isolation effect, so that the binding force between the multi-layer metal foil and the base foil is weakened, and the stripping difficulty of the subsequent multi-layer metal foil is reduced. In one embodiment, before the step of unreeling the base foil, plating a plurality of metal layers on the surface of the base foil during unreeling to form a plurality of metal foils on the surface of the base foil, the method further comprises the steps of: An insulating layer is provided on one surface of the base foil, the other surface of the base foil remaining conductive. By providing an insulating layer on one surface of the base foil, a multilayer metal foil is processed only on the surface that remains conductive. In one embodiment, the substrate foil is unreeled, and the step of plating a plurality of metal layers on the surface of the substrate foil to form a plurality of metal foils on the surface of the substrate foil during unreeling further comprises the steps of: Both surfaces of the base foil are kept conductive. By keeping both surfaces of the base foil conductive, a multi-layer metal foil can be processed on both surfaces of the base foil, respectively, to achieve higher processing efficiency. In one of the embodiments, the thickness of the base foil is set in the range of 4 μm-20 μm. Because the base foil is only used as a temporary substrate, the structure of the multilayer metal foil is not formed, and the thickness of the multilayer metal foil is not influenced, the base foil can be made of thicker materials to ensure the structural strength, and the stability and the processing quality in the subsequent metal layer processing process are ensured. In one of the embodiments, the thickness of the base foil is set in the range of 5 μm-15 μm. In one embodiment, the base foil is constructed as a stainless steel foil, a titanium foil, a nickel-chromium foil, or a nickel foil. The structural strength of the metal foil materials such as stainless steel foil, titanium foil, nickel