Surface-treated copper foil for lithium ion secondary battery, and current collector and lithium ion secondary battery

Patent metadata

Field	Value
Publication number	US-2025300188-A1
Application number	US-202519086646-A
Country	US
Kind code	A1
Filing date	Mar 21, 2025
Priority date	Mar 22, 2024
Publication date	Sep 25, 2025
Grant date	—

Abstract

Provided is a surface-treated copper foil for a lithium ion secondary battery, including a copper layer having a first side and an opposite second side and nickel-containing treatment layers disposed on the first side and the second side of the copper layer respectively, wherein a nickel coating amount on each side of the copper layer is ≥3.0 104 μg/dm2, and each treatment layer provides a treated surface with lightness value (L*) of color space of 30 to 60 and reduced dale height (Svk) of 0.10 to 0.65 μm. Provided also are a current collector for a lithium ion secondary battery and a lithium ion secondary battery.

First claim

1 . A surface-treated copper foil for a lithium ion secondary battery, comprising:
a copper layer having a first side and an opposite second side; and a treatment layer disposed on the first side or the second side of the copper layer, wherein the treatment layer contains nickel, wherein a nickel coating amount on the first side or the second side of the copper layer is ≥3.0 10 4 μg/dm 2 , wherein the treatment layer provides a treated surface having a chromaticity L* value of 30-60 and a reduced dale height (Svk) of 0.10-0.65 μm.

2 . The surface-treated copper foil of claim 1 , wherein the surface-treated copper foil comprises another treatment layer, and each of the treatment layers is disposed on the first side and the second side of the copper layer, respectively.

3 . The surface-treated copper foil of claim 1 , wherein the nickel coating amount on the copper layer is from 3.0×10 4 to 21.5×10 4 μg/dm 2 .

4 . The surface-treated copper foil of claim 1 , wherein the nickel coating amount on the copper layer is from 4.0×10 4 to 20.0×10 4 μg/dm 2 .

5 . The surface-treated copper foil of claim 1 , wherein the nickel coating amount on the copper layer is from 4.5×10 4 to 18.5×10 4 μg/dm 2 .

6 . The surface-treated copper foil of claim 1 , wherein the reduced dale height (Svk) of the treated surface is from 0.10 to 0.45 μm.

7 . The surface-treated copper foil of claim 1 , wherein a chromaticity a* value of the treated surface is from −5 to 5.

8 . The surface-treated copper foil of claim 1 , wherein a chromaticity b* value of the treated surface is from −5 to 5.

9 . The surface-treated copper foil of claim 1 , wherein an electrical conductivity of the surface-treated copper foil is ≥3.2×10 7 S/m.

10 . The surface-treated copper foil of claim 1 , wherein the copper layer is an electrolytic copper foil or a rolled copper foil.

11 . A current collector for a lithium ion secondary battery, comprising the surface-treated copper foil of claim 1 .

12 . A lithium ion secondary battery, comprising the current collector of claim 11 .

13 . The lithium ion secondary battery of claim 12 , wherein the lithium ion secondary battery comprises a solid-state electrolyte.

Assignees

• Chang Chun Petrochemical Co Ltd

Inventors

• Shih You-Lin
• Hsu Kun-Lin
• Cheng Kuei-Sen

Classifications

• Y02E60/10

  Energy storage using batteries · CPC title

• H01M10/0562

  Solid materials · CPC title

• H01M10/052

  Li-accumulators · CPC title

• H01M4/667

  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