Patent ID: 7914926

Claim:
A flat-shaped battery comprising: an outer can having an opening at its upper end; a gasket disposed at an inner edge of the opening; and a sealing plate that seals the opening together with the gasket, wherein the outer can houses a power generation element, the sealing plate is fixed to the inner edge of the opening of the outer can via the gasket by caulking, an organic bright nickel plating layer or an organic bright nickel-containing plating layer is formed on an outer surface and an inner surface of a base composing the outer can, a gold plating layer or a gold-containing plating layer is formed on an outer surface of the organic bright nickel plating layer or the organic bright nickel-containing plating layer that is formed on the outer surface and the inner surface of the base, the base is formed of iron, and the organic bright nickel plating layer or the organic bright nickel-containing plating layer has a thickness in a range from 4 to 10 μm.