CN115036514A

CN115036514A - Preparation method of composite current collector and composite current collector

Info

Publication number: CN115036514A
Application number: CN202210753320.9A
Authority: CN
Inventors: 王成豪; 李学法; 张国平
Original assignee: Yangzhou Nanopore Innovative Materials Technology Ltd
Current assignee: Yangzhou Nanopore Innovative Materials Technology Ltd
Priority date: 2022-06-29
Filing date: 2022-06-29
Publication date: 2022-09-09
Also published as: WO2024000803A1

Abstract

The invention relates to a preparation method of a composite current collector and the composite current collector, wherein the preparation method of the composite current collector comprises the following steps: ionizing metallic nickel to generate nickel ions; under the action of a magnetic field, nickel ions bombard the two surfaces of the film base material layer, which are arranged in the back of the film base material layer, at a high speed so as to form a metal nickel layer on the two surfaces of the film base material layer, which are arranged in the back of the film base material layer. According to the invention, nickel ions bombard the surface of the thin film base material layer at a high speed, so that the nickel ions can be combined with the negative charge polar group on the surface of the thin film base material layer to generate a chemical bond; through set up the metallic nickel layer between metallic coating and film substrate layer, can improve the cohesion and the peel strength of metallic coating and film substrate layer for the metallic coating is difficult for taking place to drop with the film substrate layer, thereby guarantees the electrical property and the security of battery, and can solve and take place the layering easily at the in-process of cutting, causes the product bad and takes place to fall the material phenomenon at the in-process of film-making, causes the problem of serious product defect.

Description

Preparation method of composite current collector and composite current collector

Technical Field

The invention relates to the technical field of lithium ion batteries, in particular to a preparation method of a composite current collector and the composite current collector.

Background

The current composite current collector mainly comprises a copper current collector and an aluminum current collector, wherein the copper current collector or the aluminum current collector comprises two parts, and comprises a film substrate layer arranged in the middle and metal coatings arranged on two surfaces of the film substrate layer, which are arranged back to back. The thickness requirement of the metal coating is generally about 0.5-1.5 μm, the preparation of the composite current collector is completed by an evaporation process, but the bonding force of the metal coating and the polar group of the negative charge on the film base material layer is poor, so that the stripping force between the metal coating and the film base material layer is poor, the composite current collector is easy to delaminate in the slitting process, the product is poor, the material dropping phenomenon of the battery pole piece in the sheet making process can be caused, and the serious product defect is caused; meanwhile, the battery can be caused to expand and contract in a breathing mode in the use process, so that the metal coating and the film base material layer are caused to fall off, the positive and negative electrode interfaces in the battery are influenced, the electrical property of the battery is poor, and the safety of the battery is also influenced.

Disclosure of Invention

Based on this, it is necessary to provide a preparation method of a composite current collector and a composite current collector, which can improve the binding force and the peeling force between a metal coating and a film substrate layer, so that the metal coating and the film substrate layer are not easy to fall off, thereby ensuring the electrical performance and the safety of a battery, and can solve the problems that the product is poor due to easy layering in the slitting process, the material falling phenomenon occurs in the sheet making process, and the serious product defect is caused.

A preparation method of a composite current collector comprises the following steps:

ionizing metallic nickel to generate nickel ions;

under the action of a magnetic field, enabling the nickel ions to bombard two surfaces of the film base material layer, which are arranged in a back-to-back manner, at a high speed so as to form metal nickel layers on the two surfaces of the film base material layer, which are arranged in the back-to-back manner;

and evaporating a metal coating on the surface of the metal nickel layer.

In one embodiment, the purity of the metal plating layer and the purity of the metal nickel layer are both more than or equal to 99.8 percent.

In one embodiment, the metal plating layer is a metal aluminum layer or a metal copper layer.

In one embodiment, the thickness of the thin film substrate layer ranges from 1 μm to 25 μm, and the thickness of the metal plating layer ranges from 0.5 μm to 1.5 μm.

In one embodiment, the thickness of the metallic nickel layer is in the range of 0.5 μm to 1 μm.

In one embodiment, the puncture strength of the film base material layer is more than or equal to 100gf, the MD tensile strength is more than or equal to 200MPa, the TD tensile strength is more than or equal to 200MPa, the MD elongation is more than or equal to 30%, and the TD elongation is more than or equal to 30%.

In one embodiment, the thin film substrate layer includes at least one of an insulating polymer material, an insulating polymer composite material, a conductive polymer material, and a conductive polymer composite material.

In one embodiment, the insulating polymer material includes at least one of Polyamide (PA), polyester terephthalate, Polyimide (PI), Polyethylene (PE), polypropylene (PP), polystyrene (PPE), polyvinyl chloride (PVC), aramid, acrylonitrile-butadiene-styrene copolymer (ABS), polybutylene terephthalate (PET), poly (paraphenylene terephthalamide) (PPTA), polypropylene (PPE), Polyoxymethylene (POM), epoxy resin, phenol resin, Polytetrafluoroethylene (PTEE), polyvinylidene fluoride (PVDF), silicone rubber, Polycarbonate (PC), polyvinyl alcohol (PVA), polyethylene glycol (PEG), cellulose, starch, proteins, their derivatives, their cross-linked compounds, and their copolymers.

In one embodiment, the insulating polymer composite is a composite formed by the insulating polymer material and an inorganic material.

The present application further provides a composite current collector, including:

the film substrate layer, film substrate layer back to back is equipped with respectively in proper order on two surfaces that set up the metal nickel layer with the metal coating.

In the scheme, the nickel metal is ionized to generate nickel ions, and the nickel ions bombard two oppositely arranged surfaces of the thin film base material layer at a high speed under the action of a magnetic field, so that the positively charged nickel ions can be combined with the negative charge polar groups on the surface of the thin film base material layer to form more chemical bonds on the surface of the thin film base material layer, and the bonding force and the stripping force between the thin film base material layer and the metal nickel layer are improved; through set up the metallic nickel layer between metallic coating and film substrate layer, can improve the cohesion and the peel strength of metallic coating and film substrate layer for the metallic coating is difficult for taking place to drop with the film substrate layer, thereby guarantees the electrical property and the security of battery, and can solve and take place the layering easily at the in-process of cutting, causes the product bad and takes place to fall the material phenomenon at the in-process of film-making, causes the problem of serious product defect, ensures product quality.

Drawings

The accompanying drawings, which are incorporated in and constitute a part of this application, illustrate embodiments of the invention and, together with the description, serve to explain the invention and not to limit the invention.

In order to more clearly illustrate the technical solutions in the embodiments of the present invention, the drawings needed to be used in the description of the embodiments will be briefly introduced below, and it is obvious that the drawings in the following description are only some embodiments of the present invention, and it is obvious for those skilled in the art to obtain other drawings based on these drawings without creative efforts.

Fig. 1 is a schematic structural diagram of a composite current collector according to an embodiment of the present invention;

fig. 2 is a schematic flow chart illustrating steps of a method for manufacturing a composite current collector according to an embodiment of the present invention;

fig. 3 is a schematic flow chart illustrating steps of a method for manufacturing a composite current collector according to a comparative example of the present invention.

Description of the reference numerals

10. Compounding a current collector; 100. a thin film substrate layer; 200. a layer of metallic nickel; 300. and (5) plating a metal layer.

Detailed Description

In order to make the aforementioned objects, features and advantages of the present invention comprehensible, embodiments accompanied with figures are described in detail below. In the following description, numerous specific details are set forth in order to provide a thorough understanding of the present invention. This invention may, however, be embodied in many different forms and should not be construed as limited to the embodiments set forth herein.

In the description of the present invention, it is to be understood that the terms "central," "longitudinal," "lateral," "length," "width," "thickness," "upper," "lower," "front," "rear," "left," "right," "vertical," "horizontal," "top," "bottom," "inner," "outer," "clockwise," "counterclockwise," "axial," "radial," "circumferential," and the like are used in the orientations and positional relationships indicated in the drawings for convenience in describing the invention and to simplify the description, and are not intended to indicate or imply that the referenced device or element must have a particular orientation, be constructed and operated in a particular orientation, and are not to be considered limiting of the invention.

Furthermore, the terms "first", "second" and "first" are used for descriptive purposes only and are not to be construed as indicating or implying relative importance or to implicitly indicate the number of technical features indicated. Thus, a feature defined as "first" or "second" may explicitly or implicitly include at least one such feature. In the description of the present invention, "a plurality" means at least two, e.g., two, three, etc., unless specifically limited otherwise.

In the present invention, unless otherwise expressly stated or limited, the terms "mounted," "connected," "secured," and the like are to be construed broadly and can, for example, be fixedly connected, detachably connected, or integrally formed; can be mechanically or electrically connected; they may be directly connected or indirectly connected through intervening media, or they may be connected internally or in any other suitable relationship, unless expressly stated otherwise. The specific meanings of the above terms in the present invention can be understood by those skilled in the art according to specific situations.

In the present invention, unless otherwise expressly stated or limited, the first feature "on" or "under" the second feature may be directly contacting the first and second features or indirectly contacting the first and second features through an intermediate. Also, a first feature "on," "above," and "over" a second feature may be directly on or obliquely above the second feature, or simply mean that the first feature is at a higher level than the second feature. A first feature being "under," "below," and "beneath" a second feature may be directly under or obliquely under the first feature, or may simply mean that the first feature is at a lesser elevation than the second feature.

It will be understood that when an element is referred to as being "secured to" or "disposed on" another element, it can be directly on the other element or intervening elements may also be present. When an element is referred to as being "connected" to another element, it can be directly connected to the other element or intervening elements may also be present. The terms "vertical," "horizontal," "upper," "lower," "left," "right," and the like as used herein are for illustrative purposes only and do not denote a unique embodiment.

Referring to fig. 1 and fig. 2, an embodiment of the present application further provides a method for preparing a composite current collector 10, including the following steps:

step 1: the metallic nickel is ionized to produce nickel ions.

Step 2: under the action of a magnetic field, nickel ions bombard the two surfaces of the film substrate layer 100, which are arranged oppositely, at a high speed, so that the metal nickel layer 200 is respectively formed on the two surfaces of the film substrate layer 100, which are arranged oppositely. It is to be understood that: when the nickel ions bombard the two surfaces of the film base material layer 100, which are opposite to each other, at a high speed, the positively charged nickel ions can combine with the negative charge polar groups on the surface of the film base material layer 100 to form more chemical bonds on the surface of the film base material layer 100, so as to improve the binding force and the stripping force between the film base material layer 100 and the metal nickel layer 200.

The speed of nickel ion bombardment film substrate layer 100 back to back two surfaces that set up does not do the restriction in this application, can set for by oneself according to the user demand. Illustratively, the velocity of the nickel ions bombarding the two oppositely disposed surfaces of the thin-film substrate layer 100 is 150 m/s.

It is more to be understood that: the processes of ionizing the metal nickel to generate nickel ions and forming the metal nickel layer 200 on the two oppositely arranged surfaces of the film substrate layer 100 are all performed in a vacuum environment to reduce impurities in the metal nickel layer 200.

And step 3: a metal plating layer 300 is deposited on the surface of the metallic nickel layer 200. After the composite current collector 10 is manufactured, the composite current collector 10 is slit, rolled and vacuum-packed.

Referring to FIG. 1, according to some embodiments of the present application, the metal coating 300 may optionally have a purity of 99.8% or more. That is, the metal plating layer 300 in the present application uses a high-purity metal. Specifically, the metal plating layer 300 is a metal aluminum layer or a metal copper layer. The purity of the metallic nickel layer 200 is more than or equal to 99.8 percent. That is, the metallic nickel layer 200 in the present application is a metallic nickel of high purity. The high-purity metal nickel has excellent corrosion resistance, higher electric vacuum performance and electromagnetic control performance.

In one embodiment, the metal coating 300 is a metal aluminum layer with a purity of 99.8% or more. The high-purity metal aluminum layer has the properties of low deformation resistance, high conductivity, good plasticity and the like. In another embodiment, the metal plating layer 300 is a copper metal layer with a purity of 99.8% or more. The high-purity metal copper layer has good ductility, heat conductivity and electrical conductivity.

The peeling force between the metal coating 300 and the polymer film layer is more than or equal to 8N/m. Illustratively, the peel force between the metal plating layer 300 and the thin film base layer 100 is 10N/m. The peeling force between the metal plating layer 300 and the film base material layer 100 is high, so that the metal plating layer 300 and the film base material layer 100 are not easy to fall off, and the electrical property and the safety of the battery are ensured.

Referring to fig. 1, according to some embodiments of the present disclosure, optionally, the thickness of the thin film substrate layer 100 ranges from 1 μm to 25 μm, and the thickness of the metal plating layer 300 ranges from 0.5 μm to 1.5 μm. The thickness of the metallic nickel layer 200 is in the range of 0.5 μm to 1 μm. It is to be understood that: the composite current collector 10 of the present application has a thickness in the range of 3 μm to 30 μm. Illustratively, the thickness of the thin film substrate layer 100 is 20 μm, and the thickness of the metal plating layer 300 is 1.2 μm. The thickness of the metallic nickel layer 200 is 1 μm.

Referring to FIG. 1, according to some embodiments of the present application, optionally, the thin film substrate layer 100 has a puncture strength of 100gf or more, an MD tensile strength of 200MPa or more, a TD tensile strength of 200MPa or more, an MD elongation of 30% or more, and a TD elongation of 30% or more. Illustratively, the puncture strength of the film base material layer 100 is equal to or greater than 300f, the MD tensile strength is equal to or greater than 400MPa, the TD tensile strength is equal to or greater than 400MPa, the MD elongation is equal to or greater than 50%, and the TD elongation is equal to or greater than 50%. It should be noted that: MD (Machine Direction) refers to the longitudinal Direction and TD (Transverse Direction) refers to the Transverse Direction.

It should be noted that: the upper limits of the puncture strength, MD tensile strength, TD tensile strength, MD elongation, and TD elongation of the film base layer 100 are not limited in this application, and can be set by the user as needed. The lower limit of the puncture strength of the film substrate layer 100 should not be lower than 100gf, the lower limit of the MD tensile strength should not be lower than 200MPa, the lower limit of the TD tensile strength should not be lower than 200MPa, the lower limit of the MD elongation should not be lower than 30%, and the lower limit of the TD elongation should not be lower than 30%, otherwise the mechanical properties of the film substrate layer 100 may be affected, and finally the puncture strength, MD tensile strength, TD tensile strength, MD elongation, and TD elongation of the composite current collector 10 may be affected.

Referring to fig. 1, according to some embodiments of the present application, optionally, the film substrate layer 100 includes at least one of an insulating polymer material, an insulating polymer composite material, a conductive polymer material, and a conductive polymer composite material.

Specifically, the insulating polymer material includes at least one of Polyamide (PA), polyester terephthalate, Polyimide (PI), Polyethylene (PE), polypropylene (PP), polystyrene (PPE), polyvinyl chloride (PVC), aramid, acrylonitrile-butadiene-styrene copolymer (ABS), polybutylene terephthalate (PET), polyparaphenylene terephthalamide (PPTA), polypropylene (PPE), Polyoxymethylene (POM), epoxy resin, phenol resin, Polytetrafluoroethylene (PTEE), polyvinylidene fluoride (PVDF), Silicone rubber (Silicone rubber), Polycarbonate (PC), polyvinyl alcohol (PVA), polyethylene glycol (PEG), cellulose, starch, protein, their derivatives, their crosslinked products, and their copolymers.

The insulating polymer composite material is a composite material formed by an insulating polymer material and an inorganic material. Wherein the inorganic material may be at least one of a ceramic material, a glass material, and a ceramic composite material.

The conductive polymer material may be at least one of doped polysulphide and doped polyacetylene.

The conductive polymer composite material may be a composite material formed by an insulating polymer material and a conductive material. Specifically, the conductive material may be at least one of a conductive carbon material, a metal material, and a composite conductive material. More specifically, the conductive carbon material is selected from at least one of carbon black, carbon nanotube, graphite, acetylene black, and graphene. The metal material is selected from at least one of metal nickel, metal iron, metal copper, metal aluminum or alloy of the above metals. The composite conductive material is selected from at least one of graphite powder coated by metallic nickel and carbon fiber coated by metallic nickel.

Referring to fig. 1, an embodiment of the present application further provides a composite current collector 10, which includes a film substrate layer 100, and a metal nickel layer 200 and a metal plating layer 300 are sequentially disposed on two opposite surfaces of the film substrate layer 100, respectively.

Through set up metallic nickel layer 200 at film substrate layer 100 and metallic coating 300, can improve the cohesion and the peel strength of film substrate layer 100 and metallic coating 300 for metallic coating 300 is difficult for taking place the phenomenon that drops with film substrate layer 100, thereby guarantees the electrical property and the security of battery, has improved the quality of product.

The puncture strength of the composite current collector 10 is more than or equal to 50gf, the MD tensile strength is more than or equal to 150MPa, the TD tensile strength is more than or equal to 150MPa, the MD elongation is more than or equal to 10%, and the TD elongation is more than or equal to 10%. Illustratively, the composite current collector 10 has a puncture strength of 130gf, an MD tensile strength of 300MPa, and a TD tensile strength of 300 MPa. The MD elongation was 60% and the TD elongation was 60%.

Example (b):

the present disclosure is more particularly described in the following examples that are intended as illustrations only, since various modifications and changes within the scope of the present disclosure will be apparent to those skilled in the art. Unless otherwise indicated, all parts, percentages, and ratios reported in the following examples are on a weight basis, and all reagents used in the examples are commercially available or synthesized according to conventional methods and can be used directly without further treatment, and the equipment used in the examples is commercially available.

Method for preparing composite current collector 10

Example 1:

step 1: a film substrate layer of 6 μm 100, a metallic aluminum layer of 99.9% purity, and a metallic nickel of 99.9% purity were selected. The film base layer 100 is made of polybutylene terephthalate (PET).

Step 2: the metallic nickel is ionized to generate nickel ions. Specifically, the nickel ion has a valence of + 2.

And 3, step 3: under the action of a magnetic field, nickel ions bombard the two surfaces of the film substrate layer 100, which are arranged oppositely, at a high speed, so that the metal nickel layer 200 is respectively formed on the two surfaces of the film substrate layer 100, which are arranged oppositely. Specifically, under the action of a magnetic field, nickel ions bombard two opposite surfaces of the thin film substrate layer 100 at a speed of 150 m/s. Wherein the thickness of the metallic nickel layer 200 is 0.5 μm.

And 4, step 4: a metal plating layer 300 is deposited on the surface of the metallic nickel layer 200. Wherein the thickness of the metal plating layer 300 is 0.5 μm, and the metal nickel layer 200 is a metal aluminum layer.

Finally, the composite current collector 10 with the diameter of 8 microns is prepared, and after the preparation is finished, the composite current collector 10 is cut, rolled and subjected to vacuum packaging operation.

Example 2:

step 1: selecting a film base material layer of 25 mu m 100, a metal copper layer with the purity of 99.9 percent and metal nickel with the purity of 99.9 percent. The film base layer 100 is made of polybutylene terephthalate (PET).

And 2, step: the metallic nickel is ionized to produce nickel ions. Specifically, the nickel ion has a valence of + 2.

And 3, step 3: under the action of a magnetic field, nickel ions bombard the two surfaces of the film substrate layer 100, which are arranged oppositely, at a high speed, so that the metal nickel layer 200 is respectively formed on the two surfaces of the film substrate layer 100, which are arranged oppositely. Specifically, under the action of a magnetic field, nickel ions bombard two opposite surfaces of the thin film substrate layer 100 at a speed of 150 m/s. Wherein the thickness of the metallic nickel layer 200 is 1 μm.

And 4, step 4: a metal plating layer 300 is deposited on the surface of the metallic nickel layer 200. Wherein the thickness of the metal plating layer 300 is 1.5 μm, and the metal nickel layer 200 is a metal copper layer.

Finally, the composite current collector 10 with the diameter of 30 microns is prepared, and after the preparation is finished, the composite current collector 10 is cut, rolled and subjected to vacuum packaging operation.

Example 3

Step 1: a1-micron thin film substrate layer 100, a 99.9% purity metal aluminum layer and a 99.8% purity metal nickel layer are selected. The film base layer 100 is made of polybutylene terephthalate (PET).

Step 2: the metallic nickel is ionized to produce nickel ions. Specifically, the nickel ion has a valence of + 2.

And step 3: under the action of a magnetic field, nickel ions bombard the two surfaces of the film substrate layer 100, which are arranged oppositely, at a high speed, so that the metal nickel layer 200 is respectively formed on the two surfaces of the film substrate layer 100, which are arranged oppositely. Specifically, under the action of a magnetic field, nickel ions bombard two opposite surfaces of the thin film substrate layer 100 at a speed of 150 m/s. Wherein the thickness of the metallic nickel layer 200 is 0.5 μm.

And 4, step 4: a metal plating layer 300 is deposited on the surface of the metallic nickel layer 200. Wherein the thickness of the metal plating layer 300 is 0.5 μm, and the metal nickel layer 200 is a metal copper layer.

Finally, the composite current collector 10 with the diameter of 3 microns is prepared, and after the preparation is finished, the composite current collector 10 is cut, rolled and subjected to vacuum packaging operation.

Comparative example 1:

referring to fig. 3, the method for preparing the composite current collector 10 according to the present comparative example includes the following steps:

step 1: a6-micron film substrate layer 100 and a 99.9% purity metal aluminum layer were selected. The film base layer 100 is made of polybutylene terephthalate (PET).

Step 2: respectively putting the film base material layer 100 with the thickness of 6 microns and the metal aluminum layer with the purity of 99.9% into vacuum coating equipment, and evaporating the metal aluminum layers on the two surfaces, which are opposite to each other, of the film base material layer 100 to obtain the required composite current collector 10. In this embodiment, the thickness of the metal aluminum layer is 1 μm.

Finally, the composite current collector 10 with the diameter of 8 microns is prepared. After the composite current collector 10 is manufactured, the composite current collector 10 is slit, rolled and vacuum-packed.

Comparative example 2:

the preparation method of the composite current collector 10 provided by the present comparative example includes the following steps:

step 1: a film substrate layer of 25 μm 100 and a metallic aluminum layer of 99.9% purity were selected. The film base layer 100 is made of polybutylene terephthalate (PET).

Step 2: respectively putting the film base material layer 100 with the thickness of 25 microns and the metal aluminum layer with the purity of 99.9% into vacuum coating equipment, and evaporating the metal aluminum layers on the two surfaces, which are opposite to each other, of the film base material layer 100 to obtain the required composite current collector 10. In this embodiment, the thickness of the metal aluminum layer is 2.5 μm.

Finally, 30 μm of composite current collector 10 was obtained. After the composite current collector 10 is manufactured, the composite current collector 10 is slit, rolled and vacuum-packed.

The composite current collectors 10 of examples 1-3 and comparative examples 1-2 were tested for peel force and the effect data as described in table 1 were obtained. It is to be understood that: the peeling force of the composite current collector 10 refers to the peeling force between the metal plating layer 300 and the thin film base material layer 100.

Table 1 shows peel force test data for composite current collector 10.

TABLE 1

As can be seen from the above table, the peel force of the composite current collector 10 of the present invention is greater than that of the composite current collector 10 of the comparative example, and the peel force of the composite current collector 10 is independent of the thickness of the thin film substrate layer 100, the thickness of the metal plating layer 300, and the material of the metal plating layer 300, and is related to the purity of the metal nickel layer 200, and the higher the purity of the metal nickel layer 200 is, the greater the peel force of the composite current collector 10 is.

The technical features of the embodiments described above may be arbitrarily combined, and for the sake of brevity, all possible combinations of the technical features in the embodiments described above are not described, but should be considered as being within the scope of the present specification as long as there is no contradiction between the combinations of the technical features.

The above-mentioned embodiments only express several embodiments of the present invention, and the description thereof is more specific and detailed, but not construed as limiting the scope of the invention. It should be noted that, for a person skilled in the art, several variations and modifications can be made without departing from the inventive concept, which falls within the scope of the present invention. Therefore, the protection scope of the present patent shall be subject to the appended claims.

Claims

1. The preparation method of the composite current collector is characterized by comprising the following steps of:

ionizing metallic nickel to generate nickel ions;

under the action of a magnetic field, enabling the nickel ions to bombard two surfaces of the film base material layer, which are arranged oppositely, at a high speed so as to form metal nickel layers on the two surfaces of the film base material layer, which are arranged oppositely, respectively;

and evaporating a metal coating on the surface of the metal nickel layer.

2. The method for preparing the composite current collector as claimed in claim 1, wherein the purity of the metal plating layer and the purity of the metal nickel layer are both greater than or equal to 99.8%.

3. The method for preparing a composite current collector as claimed in claim 1, wherein the metal plating layer is a metal aluminum layer or a metal copper layer.

4. The method for preparing a composite current collector as claimed in claim 1, wherein the thin film substrate layer has a thickness ranging from 1 μm to 25 μm, and the metal plating layer has a thickness ranging from 0.5 μm to 1.5 μm.

5. The method for manufacturing a composite current collector according to claim 1, wherein the metallic nickel layer has a thickness in the range of 0.5 μ ι η to 1 μ ι η.

6. The preparation method of the composite current collector as claimed in claim 1, wherein the puncture strength of the thin film substrate layer is not less than 100gf, the MD tensile strength is not less than 200MPa, the TD tensile strength is not less than 200MPa, the MD elongation is not less than 30%, and the TD elongation is not less than 30%.

7. The method of claim 1, wherein the thin film substrate layer comprises at least one of an insulating polymer material, an insulating polymer composite material, a conductive polymer material, and a conductive polymer composite material.

8. The method of preparing the composite current collector of claim 7, wherein the insulating polymer material comprises at least one of Polyamide (PA), polyester terephthalate, Polyimide (PI), Polyethylene (PE), polypropylene (PP), polystyrene (PPE), polyvinyl chloride (PVC), aramid, acrylonitrile-butadiene-styrene copolymer (ABS), polybutylene terephthalate (PET), polyparaphenylene terephthalamide (PPTA), polypropylene (PPE), Polyoxymethylene (POM), epoxy resin, phenolic resin, Polytetrafluoroethylene (PTEE), polyvinylidene fluoride (PVDF), silicone rubber, Polycarbonate (PC), polyvinyl alcohol (PVA), polyethylene glycol (PEG), cellulose, starch, protein, derivatives thereof, cross-linked materials thereof, and copolymers thereof.

9. The method for preparing the composite current collector of claim 7, wherein the insulating polymer composite material is a composite material formed by the insulating polymer material and an inorganic material.

10. A composite current collector manufactured by the method of manufacturing a composite current collector as claimed in any one of claims 1 to 9, comprising: