A current collector and graphite anode bipolar lithium ion battery

Abstract

The present invention belongs to the technical field of lithium-ion batteries and relates to a current collector and a graphite anode bipolar lithium-ion battery, comprising a first metal coating, a first plastic film, a second plastic film and the second metal coating, wherein a first end of the first plastic film is connected to one side of the second metal coating, a first end of the second plastic film is connected to the other side of the second metal coating, the second metal coating covers the lower surface of the first and second plastic films, the second metal coating is in contact with the lower surface of the first metal coating, the second end of the first plastic film protrudes from the first and second metal coatings, and the second end of the second plastic film protrudes from the first and second metal coatings; in the current collector of the present application, the first plastic film and the second plastic film on both sides can be used for packaging between the current collectors; the bipolar battery produced is lighter in weight and has no risk of oxidation and lithium insertion.

Description

Technical Field

[0001] The present invention belongs to the technical field of lithium ion batteries and relates to a current collector and a graphite anode bipolar lithium ion battery. Background Art

[0002] Lithium-ion batteries, with their advantages of large capacity, high operating voltage, strong charge retention, and high safety, have been widely used in consumer electronics and electric vehicles. With the development of new energy vehicles, people have placed higher demands on their range.

[0003] The current mainstream bipolar lithium-ion battery has a positive electrode and a negative electrode on both sides of the current collector, a separator is placed between adjacent bipolar electrodes, and an electrolyte is added to form a multi-layered energy storage device.

[0004] However, this type of bipolar lithium-ion battery is prone to holes and is also prone to oxidation and lithium insertion risks. Summary of the Invention

[0005] The technical problem to be solved by the present invention is: to provide a current collector and a graphite anode bipolar lithium ion battery in view of the problem that existing bipolar lithium ion batteries are prone to oxidation and lithium insertion risks.

[0006] To solve the above technical problems, the present invention provides a current collector, comprising a first metal coating, a first plastic film, a second plastic film, and the second metal coating, wherein the first plastic film and the second plastic film are spaced apart, a first end of the first plastic film is connected to one side of the second metal coating, a first end of the second plastic film is connected to the other side of the second metal coating, the second metal coating covers the lower surfaces of the first and second plastic films, the second metal coating is in contact with the lower surface of the first metal coating, a second end of the first plastic film protrudes beyond the first and second metal coatings, and a second end of the second plastic film protrudes beyond the first and second metal coatings.

[0007] Optionally, the first metal plating layer is a copper plating layer.

[0008] Optionally, the copper plating layer is a graphite-doped plating layer.

[0009] Optionally, the second metal coating has a stepped section and a planar section, the stepped section is connected to the lower surface of the first metal coating, the first end of the first plastic film is connected to one side of the stepped section, and the first end of the second plastic film is connected to the other side of the stepped section, and the stepped section has the same thickness as the first plastic film and the second plastic film.

[0010] Optionally, the thickness of the first metal coating is 0.5-2 microns;

[0011] The second metal coating is an aluminum coating and forms a bipolar current collector with the first metal coating. The thickness of the planar segment is 0.5-2 microns.

[0012] Optionally, the first plastic film and the second plastic film are PET films.

[0013] Optionally, the first metal coating is covered on the upper surfaces of the first plastic film and the second plastic film by evaporation;

[0014] The second metal coating is covered on the lower surfaces of the first plastic film and the second plastic film by evaporation.

[0015] Optionally, the thickness of the first plastic film is 1-50 microns, the thickness of the second plastic film is 1-50 microns, the thickness of the stepped section is 1-50 microns, and the thickness of the planar section is 1-50 microns.

[0016] The current collector provided by an embodiment of the present invention includes a first metal coating, a first plastic film, a second plastic film and a second metal coating, the first plastic film and the second plastic film are spaced apart, the first end of the first plastic film is connected to one side of the second metal coating, the first end of the second plastic film is connected to the other side of the second metal coating, the second metal coating covers the lower surface of the first plastic film and the second plastic film, the second metal coating is connected to the lower surface of the first metal coating, the second end of the first plastic film protrudes from the first metal coating and the second metal coating, and the second end of the second plastic film protrudes from the first metal coating and the second metal coating; the current collector of the present application, the first plastic film and the second plastic film on both sides can be used for packaging between the current collectors; the bipolar battery produced is lighter in weight and has no risk of oxidation and lithium insertion.

[0017] On the other hand, an embodiment of the present invention further provides a graphite anode bipolar lithium ion battery, which includes the above-mentioned current collector. BRIEF DESCRIPTION OF THE DRAWINGS

[0018] Figure 1 Schematic diagram of a current collector provided by an embodiment of the present invention.

[0019] The reference numerals in the specification are as follows:

[0020] 2. First metal coating; 5. First plastic film; 6. Second plastic film; 7. Second metal coating; 71. Step section; 72. Plane section. DETAILED DESCRIPTION

[0021] In order to make the technical problems, technical solutions and beneficial effects solved by the present invention more clearly understood, the present invention is further described in detail below with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are only used to explain the present invention and are not intended to limit the present invention.

[0022] like Figure 1 As shown, the current collector provided by an embodiment of the present invention includes a first metal coating 2, a first plastic film 5, a second plastic film 6 and a second metal coating 7, wherein the first plastic film 5 and the second plastic film 6 are spaced apart, the first end of the first plastic film 5 is connected to one side of the second metal coating 7, the first end of the second plastic film 6 is connected to the other side of the second metal coating 7, the second metal coating 7 covers the lower surface of the first plastic film 5 and the second plastic film 6, the second metal coating 7 is in contact with the lower surface of the first metal coating 2, the second end of the first plastic film 5 protrudes from the first metal coating 2 and the second metal coating 7, and the second end of the second plastic film 6 protrudes from the first metal coating 2 and the second metal coating 7.

[0023] The first plastic film 5 and the second plastic film 6 on both sides can be used for packaging between current collectors; the manufactured bipolar battery is lighter in weight, etc.

[0024] In one embodiment, the first metal plating layer 2 is a copper plating layer.

[0025] In one embodiment, the copper plating layer is a graphite-doped plating layer.

[0026] In one embodiment, the second metal coating 7 has a stepped section 71 and a flat section 72, the stepped section 71 is connected to the lower surface of the first metal coating 2, the first end of the first plastic film 5 is connected to one side of the stepped section 71, and the first end of the second plastic film 6 is connected to the other side of the stepped section 71, and the stepped section 71 has the same thickness as the first plastic film 5 and the second plastic film 6.

[0027] In one embodiment, the thickness of the first metal coating layer 2 is 0.5-2 microns.

[0028] The second metal coating 7 is an aluminum coating and forms a bipolar current collector with the first metal coating 2. The thickness of the planar section 72 is 0.5-2 microns.

[0029] In one embodiment, the first plastic film 5 and the second plastic film 6 are PET films.

[0030] In one embodiment, the first metal coating layer 2 is covered on the upper surfaces of the first plastic film 5 and the second plastic film 6 by evaporation.

[0031] The second metal coating 7 is covered on the lower surfaces of the first plastic film 5 and the second plastic film 6 by evaporation.

[0032] In one embodiment, the thickness of the first plastic film 5 is 1-50 microns, the thickness of the second plastic film 6 is 1-50 microns, the thickness of the stepped section 71 is 1-50 microns, and the thickness of the planar section 72 is 1-50 microns.

[0033] Optionally, the first metal coating layer and the second metal coating layer may be made of the same metal or different metals.

[0034] According to the current collector of an embodiment of the present invention, the first plastic film and the second plastic film are spaced apart, the first end of the first plastic film is connected to one side of the second metal coating, the first end of the second plastic film is connected to the other side of the second metal coating, the second metal coating covers the lower surface of the first plastic film and the second plastic film, the second metal coating is connected to the lower surface of the first metal coating, the second end of the first plastic film protrudes from the first metal coating and the second metal coating, and the second end of the second plastic film protrudes from the first metal coating and the second metal coating; in the current collector of the present application, the first plastic film and the second plastic film on both sides can be used for packaging between the current collectors; the bipolar battery produced is lighter in weight and has no risk of oxidation and lithium insertion.

[0035] In addition, an embodiment of the present invention further provides a graphite anode bipolar lithium ion battery, which includes the current collector of the above embodiment.

[0036] The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent substitutions and improvements made within the spirit and principles of the present invention should be included in the scope of protection of the present invention.

Claims

1. A current collector, characterized in that: It includes a first metal coating, a first plastic film, a second plastic film and a second metal coating, The first metal coating is a copper coating, which is a graphite-doped coating, and the second metal coating is an aluminum coating and forms a bipolar current collector with the first metal coating; The first plastic film and the second plastic film are spaced apart from each other, the first end of the first plastic film is connected to one side of the second metal coating, the first end of the second plastic film is connected to the other side of the second metal coating, the second metal coating covers the lower surfaces of the first and second plastic films, the second metal coating is in contact with the lower surface of the first metal coating, the second end of the first plastic film protrudes from the first and second metal coatings, and the second end of the second plastic film protrudes from the first and second metal coatings.

2. The current collector according to claim 1, characterized in that The second metal coating has a stepped section and a planar section, the stepped section is connected to the lower surface of the first metal coating, the first end of the first plastic film is connected to one side of the stepped section, and the first end of the second plastic film is connected to the other side of the stepped section, and the stepped section has the same thickness as the first plastic film and the second plastic film.

3. The current collector according to claim 2, characterized in that The thickness of the first metal coating is 0.5-2 microns; the thickness of the planar segment is 0.5-2 microns.

4. The current collector according to claim 1, characterized in that The first plastic film and the second plastic film are PET films.

5. The current collector according to claim 1, characterized in that The first metal coating is covered on the upper surfaces of the first plastic film and the second plastic film by evaporation; The second metal coating is covered on the lower surfaces of the first plastic film and the second plastic film by evaporation.

6. The current collector according to claim 2, characterized in that The thickness of the first plastic film is 1-50 microns, the thickness of the second plastic film is 1-50 microns, and the thickness of the stepped section is 1-50 microns.

7. A graphite anode bipolar lithium ion battery, characterized in that: The current collector comprises the current collector according to any one of claims 1 to 6.

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