CN217009233U

CN217009233U - Lithium battery composite current collector

Info

Publication number: CN217009233U
Application number: CN202220459335.XU
Authority: CN
Inventors: 曾清华; 杨与胜
Original assignee: Goldstone Fujian Energy Co Ltd
Current assignee: Goldstone Fujian Energy Co Ltd
Priority date: 2022-03-03
Filing date: 2022-03-03
Publication date: 2022-07-19
Anticipated expiration: 2032-03-03

Abstract

The utility model discloses a composite current collector of a lithium battery, which comprises a plastic film, and a first prefabricated bonding layer, a first copper metal layer and a second copper metal layer which are arranged on one surface of the plastic film; and the second prefabricated bonding layer, the first aluminum metal layer and the second aluminum metal layer are arranged on the other side of the plastic film. The first copper metal layer and the first aluminum metal layer are formed by magnetron sputtering coating; the second copper metal layer and the second aluminum metal layer are formed by vacuum evaporation coating. According to the composite current collector of the lithium battery, the positive current collector and the negative current collector can be continuously coated on a single device, the bipolar ultrathin current collector is manufactured, the density of the film is high, and the problems that the film is corroded and stripped can be effectively avoided in the manufacturing process.

Description

Lithium battery composite current collector

Technical Field

The utility model relates to the field of lithium ion batteries, in particular to a lithium battery composite current collector.

Background

The current collector with high conductivity, high strength, high flexibility and ultrathin thickness is the development trend of the current collector of the lithium battery in the future. The positive and negative current collectors of the current commonly used lithium battery mainly comprise an extended copper foil, an electrolytic copper foil and an extended aluminum foil; wherein, the extended copper foil and the aluminum foil can be rolled by a pair roller to be generally made into 10-16um, but the extended copper foil and the aluminum foil are difficult to be continuously thinned, and the quality of a finished product cannot be further improved; the electrolytic copper solution can be used for producing copper foils with the thickness of 6-8um in mass production, but the electrolytic characteristic can cause overlarge surface roughness on two sides of the copper foil, an additional surface treatment procedure is needed to be added, and the treatment process of the electrolyte is easy to cause extra pollution, so that the whole process is too complex; particularly, for the process of integrating the positive and negative electrode current collectors, it is more difficult to achieve due to incomplete compatibility of the electrolyte with the opposite polarity metal.

Disclosure of Invention

Aiming at the problems, the utility model provides a lithium battery current collector, which combines magnetron sputtering coating and vacuum evaporation coating to realize high compactness and anti-stripping capability of a bipolar current collector and avoid corrosion of electrolyte to a metal layer.

In order to solve the technical problem, the present invention provides a composite current collector for a lithium battery, comprising: the plastic film, a first prefabricated bonding layer, a first copper metal layer and a second copper metal layer are arranged on one surface of the plastic film; and the second prefabricated bonding layer, the first aluminum metal layer and the second aluminum metal layer are arranged on the other side of the plastic film. The first copper metal layer and the first aluminum metal layer are formed by magnetron sputtering coating; the second copper metal layer and the second aluminum metal layer are formed by vacuum evaporation coating;

further, the thickness of the first copper metal layer is 30-150 nm; the second copper metal layer is 300-1500 nm;

further, the thickness of the first aluminum metal layer is 30-150 nm; the second aluminum metal layer is 300-1500 nm;

furthermore, the plastic film is made of any one of PP, PET and PI, and the thickness of the plastic film is 2-20 um;

furthermore, the first prefabricated bonding layer is made of any one of nickel, nickel copper, titanium and silicon, and the thickness of the first prefabricated bonding layer is 2-10 nm;

further, the second prefabricated bonding layer is made of any one of nickel, titanium and silicon, and the thickness of the second prefabricated bonding layer is 2-10 nm;

further, an ITO protective layer is arranged on the second copper metal layer; the thickness of the ITO protective layer is 5-20 nm.

The utility model has the beneficial effects that:

(1) the first copper metal layer and the first aluminum metal layer are formed by a vacuum magnetron sputtering coating method, and the film layer has a compact structure, good adhesion and better bonding force with a plastic film substrate; because the formed film layer is thinner, the problem that the production efficiency is influenced by the slow deposition rate is avoided;

(2) secondly, forming a thicker second copper metal layer or second aluminum metal layer on the first copper metal layer or the first aluminum metal layer by utilizing vacuum evaporation plating to realize the required metal film thickness, and improving the production efficiency;

(3) the positive current collector and the negative current collector can be continuously coated on a single device, so that the bipolar ultrathin current collector is manufactured, and the problems of corrosion and peeling of the film layer are also avoided.

In conclusion, according to the composite current collector for the lithium battery, the positive current collector and the negative current collector can be continuously coated on a single device, the manufacture of the bipolar ultrathin current collector is realized, the density of the film is high, and the problems that the film is corroded and peeled off can be effectively avoided in the manufacturing process.

Drawings

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

fig. 1 is a schematic structural diagram of a composite current collector for a lithium battery according to the present invention;

fig. 2 is a flow chart illustrating a manufacturing process of a composite current collector for a lithium battery according to the present invention;

fig. 3 is a schematic structural view of another composite current collector for a lithium battery according to the present invention;

fig. 4 is a flow chart illustrating a manufacturing process of another composite current collector for a lithium battery according to the present invention.

The reference numbers indicate: the structure comprises a plastic film 10, a first prefabricated bonding layer 20, a first copper metal layer 30, a second copper metal layer 31, a second prefabricated bonding layer 21, a first aluminum metal layer 40, a second aluminum metal layer 41 and an ITO protection layer 50.

Detailed Description

In order to make the objects, technical solutions and advantages of the present invention more apparent, the present invention is described in further detail below with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are merely illustrative of the utility model and are not intended to limit the utility model.

Embodiment 1, as shown in fig. 1, the present invention provides a composite current collector for a lithium battery, including: the plastic film comprises a plastic film 10, and a first prefabricated bonding layer 20, a first copper metal layer 30 and a second copper metal layer 31 which are arranged on one surface of the plastic film; a second prefabricated bonding layer 21, a first aluminum metal layer 40 and a second aluminum metal layer 41 which are arranged on the other side of the plastic film. The first copper metal layer 30 and the first aluminum metal layer 40 are formed by magnetron sputtering coating; the second copper metal layer 31 and the second aluminum metal layer 41 are formed by vacuum evaporation coating; the thickness of the first copper metal layer is 30-150 nm; the second copper metal layer is 300-1500 nm; the thickness of the first aluminum metal layer is 30-150 nm; the second aluminum metal layer is 300-1500 nm; the plastic film is made of any one of PP, PET and PI; the thickness of the plastic film is 2-20 um; the first prefabricated bonding layer is made of any one of nickel, nickel copper, titanium and silicon; the second prefabricated bonding layer is made of any one of nickel, titanium and silicon; the thickness of the prefabricated bonding layer is 2-10 nm;

the manufacturing flow chart of the lithium battery composite current collector is shown in fig. 2, and comprises the following steps:

providing a plastic film; the material is any one of PP, PET and PI, and the material can be a smooth surface or a rough surface made by the prior art method; the thickness is 2-20 um;

sequentially plating a first prefabricated bonding layer 2-10nm and a first copper metal layer 30-150nm on one surface of a plastic film by a magnetron sputtering coating technology, and plating a second copper metal layer 300-1500nm by a vacuum evaporation coating technology;

sequentially plating a second prefabricated bonding layer of 2-10nm and a first aluminum metal layer of 30-150nm on the other surface of the plastic film by a magnetron sputtering coating technology, and plating a second aluminum metal layer of 300-1500nm by a vacuum evaporation coating technology;

example 2

As shown in fig. 3, the present invention further provides another composite current collector for a lithium battery, which is different from embodiment 1 in that an ITO protective layer 50 is further disposed on a surface of the second copper metal layer 31, and a thickness of the ITO protective layer is 5-20 nm. The structure of the composite current collector for a lithium battery is shown in fig. 3.

Fig. 4 shows another method for manufacturing a composite current collector for a lithium battery, which is different from embodiment 1 in that the method further includes the steps of: after the second copper metal layer is completed; and plating an ITO protective layer of 5-20nm on the surface of the second copper metal layer by a magnetron sputtering coating technology. Namely, the specific manufacturing method comprises the following steps:

providing a plastic film; the material is any one of PP, PET and PI, and can be smooth surface or rough surface prepared by the prior art; the thickness is 2-20 um;

sequentially plating a first prefabricated bonding layer 2-10nm and a first copper metal layer 30-150nm on one surface of a plastic film by a magnetron sputtering coating technology, and plating a second copper metal layer 300-1500nm by a vacuum evaporation coating technology; coating an ITO protective layer by 5-20nm by a magnetron sputtering coating technology; the ITO protective layer plays a role in preventing the metal copper layer from being oxidized and reduces the influence on the conductive capability;

and sequentially plating a second prefabricated bonding layer of 2-10nm and a first aluminum metal layer of 30-150nm on the other surface of the plastic film by a magnetron sputtering coating technology, and plating a second aluminum metal layer of 300-1500nm by a vacuum evaporation coating technology.

According to the composite current collector of the lithium battery, the positive current collector and the negative current collector can be continuously coated on a single device, the bipolar ultrathin current collector is manufactured, the density of the film is high, and the problems that the film is corroded and stripped can be effectively avoided in the manufacturing process.

The above description is only for the purpose of illustrating the preferred embodiments of the present invention and is not to be construed as limiting the utility model, and any modifications, equivalents and improvements made within the spirit and principle of the present invention are intended to be included within the scope of the present invention.

Claims

1. A lithium battery composite current collector is characterized in that: the current collector includes: the plastic film, a first prefabricated bonding layer, a first copper metal layer and a second copper metal layer are arranged on one surface of the plastic film; the second prefabricated bonding layer, the first aluminum metal layer and the second aluminum metal layer are arranged on the other side of the plastic film; the first copper metal layer and the first aluminum metal layer are formed by magnetron sputtering coating; the second copper metal layer and the second aluminum metal layer are formed by vacuum evaporation coating.

2. The composite current collector for lithium batteries according to claim 1, further characterized in that: the thickness of the first copper metal layer is 30-150 nm; the second copper metal layer is 300-1500 nm.

3. The lithium battery composite current collector as recited in claim 1, further characterized by: the thickness of the first aluminum metal layer is 30-150 nm; the second aluminum metal layer is 300-1500 nm.

4. The lithium battery composite current collector as recited in claim 1, further characterized by: the plastic film material is any one of PP, PET, PI, plastic film thickness is 2-20 um.

5. The composite current collector for lithium batteries according to claim 1, further characterized in that: the first prefabricated bonding layer is made of any one of nickel, nickel copper, titanium and silicon; the thickness is 2-10 nm.

6. The lithium battery composite current collector as recited in claim 1, further characterized by: the second prefabricated bonding layer is made of any one of nickel, titanium and silicon; the thickness is 2-10 nm.

7. The composite current collector for lithium batteries according to any one of claims 1 to 6, further characterized in that: an ITO protective layer is further arranged on the second copper metal layer; the thickness of the ITO protective layer is 5-20 nm.