Electrode for lithium secondary battery and lithium secondary battery

• US 20020086215A1
• Filed: 11/13/2001
• Published: 07/04/2002
• Est. Priority Date: 11/14/2000
• Status: Active Grant

• Current Assignee: Sanyo Electric Company Limited (Panasonic Holdings Corporation)
• Original Assignee: Sanyo Electric Company Limited (Panasonic Holdings Corporation)
• Inventors: Jito, Daizo, Kamino, Maruo, Fujimoto, Masahisa, Fujitani, Shin, Ohshita, Ryuji, Tamura, Noriyuki
• Granted Patent: US 6,746,801 B2
• Time in Patent Office: Days
• US Class Current: 429/245
• CPC Class Codes: H01M 10/052 Li-accumulators
• CPC Class Codes: H01M 2004/021 Physical characteristics, e.g. porosity, surface area
• CPC Class Codes: H01M 2004/027 Negative electrodes
• CPC Class Codes: H01M 4/04 Processes of manufacture in general
• CPC Class Codes: H01M 4/0461 Electrochemical alloying
• CPC Class Codes: H01M 4/13 Electrodes for accumulators with non-aqueous electrolyte, e.g. for lithium-accumulators; Processes of manufacture thereof
• CPC Class Codes: H01M 4/38 of elements or alloys
• CPC Class Codes: H01M 4/382 Lithium H01M4/405 takes precedence
• CPC Class Codes: H01M 4/387 Tin or alloys based on tin
• CPC Class Codes: H01M 4/661 Metal or alloys, e.g. alloy coatings H01M4/669 take precedence
• CPC Class Codes: H01M 4/667 in the form of layers, e.g. coatings
• CPC Class Codes: Y02E 60/10 Energy storage using batteries
• CPC Class Codes: Y10T 29/10 Battery-grid making

Abstract

An electrode for a lithium secondary battery in which an alloy thin film containing Sn (tin) and In (indium) is formed on the surface of a current collector having a surface roughness Ra of 0.1 μm or more, and a lithium secondary battery using thereof.

Claims

1. An electrode for a lithium secondary battery wherein an alloy thin film containing Sn (tin) and In (indium) is formed on the surface of a current collector having a surface roughness Ra of not less than 0.1 μ

m.

2. The electrode for a lithium secondary battery according to claim 1, wherein the Sn content in said alloy thin film falls within the range of 10 to 90% by weight.

3. The electrode for a lithium secondary battery according to claim 1, wherein the method of forming said alloy thin film is an electrolytic plating method, an electroless plating method, a sputtering method, or a deposition method.

4. The electrode for a lithium secondary battery according to claim 1, wherein said current collector is a copper foil.

5. The electrode for a lithium secondary battery according to claim 4, wherein said copper foil is an electrolytic copper foil.

6. The electrode for a lithium secondary battery according to claim 1, wherein a mixed layer constituted by a current collector component and an alloy thin film component is formed in the interface between said current collector and said alloy thin film.

7. The electrode for a lithium secondary battery according to claim 6, wherein said mixed layer is formed by heat treatment after the alloy thin film is formed.

8. The electrode for a lithium secondary battery according to claim 1, wherein the surface roughness Ra and an average interval S between local tops of said current collector satisfy a relationship given by:

100Ra≧

S.

9. A lithium secondary battery comprising a negative electrode constituted by the electrode according to claim 1, a positive electrode, and a nonaqueous electrolyte.