Rolled copper foil for lithium ion battery current collector, and lithium ion battery

Patent metadata

Field	Value
Publication number	US-11984606-B2
Application number	US-201917289622-A
Country	US
Kind code	B2
Filing date	Aug 22, 2019
Priority date	Oct 29, 2018
Publication date	May 14, 2024
Grant date	May 14, 2024

Abstract

Provided is a rolled copper foil for a lithium ion battery current collector, which has good adhesion to a negative electrode active material, generates less metal powder during ultrasonic welding, and has a rust prevention property. In the rolled copper foil for a lithium ion battery current collector, a surface of the copper foil has a BTA film, the BTA film has a thickness of 0.6 nm or more and 4.6 nm or less, and the rolled copper foil satisfies the following relationships: 40≤wet tension [mN]/m]+thickness of BTA film [nm]×10≤80; 0.01≤arithmetic average roughness Ra [μm]≤0.25; and wet tension [mN/m]≥35.

First claim

The invention claimed is:

1. A rolled copper foil for a lithium ion battery current collector, wherein a surface of the copper foil has a benzotriazole film, the benzotriazole film has a thickness of 0.6 nm or more and 4.6 nm or less, and wherein the rolled copper foil satisfies the following relationships:
40≤wet tension [mN/m]+thickness of benzotriazole film [nm]×10≤80;
0.01≤arithmetic average roughness Ra [μm]≤0.25; and
wet tension [mN/m]≥35.

2. The rolled copper foil for a lithium ion battery current collector according to claim 1 , wherein the rolled copper foil satisfies:
45≤wet tension [mN/m]+thickness of benzotriazole film [nm]×10≤75; and
wet tension [mN/m]≥39.

3. The rolled copper foil for a lithium ion battery current collector according to claim 1 , wherein the rolled copper foil satisfies an arithmetic average roughness Ra [μm]≥0.03.

4. The rolled copper foil for a lithium ion battery current collector according to claim 1 , wherein the rolled copper foil is for a negative electrode current collector of a lithium ion secondary battery.

5. A lithium ion battery comprising the rolled copper foil for a lithium ion battery current collector according to claim 1 .

6. The rolled copper foil for a lithium ion battery current collector according to claim 2 , wherein the rolled copper foil satisfies an arithmetic average roughness Ra [μm]≥0.03.

7. The rolled copper foil for a lithium ion battery current collector according to claim 2 , wherein the rolled copper foil is for a negative electrode current collector of a lithium ion secondary battery.

8. The rolled copper foil for a lithium ion battery current collector according to claim 3 , wherein the rolled copper foil is for a negative electrode current collector of a lithium ion secondary battery.

9. The rolled copper foil for a lithium ion battery current collector according to claim 4 , wherein the rolled copper foil is for a negative electrode current collector of a lithium ion secondary battery.

10. The rolled copper foil according to claim 1 , wherein the thickness of the benzotriazole film is 2.1 nm or more and 4.6 nm or less.

Assignees

• Jx Nippon Mining & Metals Corp
• Jx Metals Corp

Inventors

• Kudo Katsuhiro

Classifications

• H01M4/667 Primary

  in the form of layers, e.g. coatings · CPC title

• H01M4/661 Primary

  Metal or alloys, e.g. alloy coatings (H01M4/669 take precedence) · CPC title

• H01M10/0525 Primary

  Rocking-chair batteries, i.e. batteries with lithium insertion or intercalation in both electrodes; Lithium-ion batteries · CPC title

• B21B1/40

  for rolling foils which present special problems, e.g. because of thinness · CPC title

• B21B2003/005

  Copper or its alloys · CPC title