An electrode having a current collector and, formed thereon, a thin film comprising an active material, characterized in that a thin alloy film (such as Sn--Co) comprising a metal which can form an alloy with lithium (such as Sn) and a metal which can not form an alloy with lithium (such as Co) is formed on a current collector such as a copper foil. It is preferred that the above metal which can form an alloy with lithium and the above metal which can not form an alloy with lithium can not form an intermetallic compound with each other.