Copper foil having improved adhesive force, electrode including the same, secondary battery including the same, and method of manufacturing the same

Patent metadata

Field	Value
Publication number	US-10741848-B2
Application number	US-201815914568-A
Country	US
Kind code	B2
Filing date	Mar 7, 2018
Priority date	Mar 9, 2017
Publication date	Aug 11, 2020
Grant date	Aug 11, 2020

Abstract

Provided is a copper foil. The copper foil includes a copper layer and a protective layer disposed on the copper layer, wherein a surface of the protective layer has a maximum height roughness (Rmax) of 0.6 μm to 3.5 μm, a peak density (PD) of 5 to 110, and an oxygen atomic amount of 22 at % (atomic %) to 67 at %.

First claim

What is claimed is:

1. A copper foil comprising:
a copper layer; and
a protective layer disposed on the copper layer,
wherein a surface of the protective layer has a maximum height roughness (R max ) of 0.6 μm to 3.5 μm, a peak density (PD) of 5 to 110, and an oxygen atomic amount of 22 at% (atomic%) to 67 at%.

2. The copper foil of claim 1 , wherein the protective layer includes at least one of chromium, a silane compound, and a nitrogen compound.

3. The copper foil of claim 1 , wherein the copper foil has a yield strength of 25 kgf/mm 2 or more at a room temperature of 25±15° C.

4. The copper foil of claim 1 , wherein the copper foil has an elongation of 2% or more at a room temperature of 25±15° C.

5. The copper foil of claim 1 , wherein the copper foil has a yield strength ratio of 0.55 kgf/mm 2 or more represented by the following Equation 1:
Yield strength ratio (kgf/mm 2 )=Yield strength(kgf/mm 2 )×Elongation value, wherein, the elongation value has no unit.   [Equation 1]

6. The copper foil of claim 1 , wherein the copper foil has a thickness of 4 μm to 30 μm.

7. A secondary battery electrode comprising:
a copper foil; and
an active material layer disposed on the copper foil,
wherein the copper foil includes:
a copper layer; and
a protective layer disposed between the copper layer and the active material layer,
wherein a surface of the copper foil has a maximum height roughness (R max ) of 0.6 μm to 3.5 μm, a peak density (PD) of 5 to 110, and an oxygen atomic amount of 22 at% to 67 at%.

8. The secondary battery electrode of claim 7 , wherein the protective layer includes at least one of chromium, a silane compound, and a nitrogen compound.

9. The secondary battery electrode of claim 7 , wherein the copper foil has a yield strength of 25 kgf/mm 2 or more and an elongation of 2% or more at a room temperature of 25±15° C.

10. A secondary battery comprising:
a cathode;
an anode including the secondary battery electrode according to any one of claims 7 to 9 ;
an electrolyte configured to provide an environment in which lithium ions move between the cathode and the anode; and
a separator configured to electrically insulate the cathode from the anode.

Assignees

• Ls Mtron Ltd
• Kcf Tech Co Ltd

Inventors

• Kim Seung Min
• Jin Shan Hua

Classifications

• Y02E60/10

  Energy storage using batteries · CPC title

• H01M4/667 Primary

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

• H01M4/13

  Electrodes for accumulators with non-aqueous electrolyte, e.g. for lithium-accumulators; Processes of manufacture thereof · CPC title

• H01M10/052

  Li-accumulators · CPC title

• C25D1/04

  Wires; Strips; Foils · CPC title