Patent ID: 7258950

Claim:
A rechargeable lithium battery comprising a positive electrode, a nonaqueous electrolyte and a negative electrode, wherein said negative electrode has a current collector and a thin alloy film provided on the current collector and composed of a metal which alloys with lithium and a metal which does not alloy with lithium, said electrode being characterized in that said current collector has a surface roughness Ra of 0.1 μm–2 μm, said thin alloy film contains 0.1–50% of the metal which does not alloy with lithium based on a molar ratio (atomic ratio), the thin alloy film has a surface with irregularities corresponding to those defined on a surface of the current collector, and the thin alloy film is separated into islands by gaps formed, on the first or subsequent cycle of charge and discharge, along lines extending in a thickness direction of the thin alloy film between valleys of the irregularities on the thin alloy film surface and on the current collector surface.