Patent ID: 7534526

Claim:
An alkaline battery comprising: a battery case that houses a power generation element therein; and an assembly sealing portion that closes an opening of said battery case, said assembly sealing portion including a negative terminal portion, a negative current collector electrically connected to said negative terminal portion, and a resin sealing body, said sealing body including a central cylindrical portion having a through hole through which said negative current collector is inserted, an outer peripheral cylindrical portion placed between a peripheral edge of said negative terminal portion and an opening end of said battery case, and a connecting portion that connects said central cylindrical portion and said outer peripheral cylindrical portion, and wherein said negative terminal portion comprises a first negative terminal plate and a second negative terminal plate spaced apart from each other, and a PTC element placed between said first negative terminal plate and said second negative terminal plate, and said connecting portion has a thin portion serving as a safety valve, wherein said first negative terminal plate and said second negative terminal plate each have a flange in a peripheral edge, a flat portion in a central portion, and a boundary portion between said flange and said flat portion, said PTC element is placed between the flat portion of said first negative terminal plate and the flat portion of said second negative terminal plate, an insulation plate is placed between the flange of said first negative terminal plate and the flange of said second negative terminal plate, the opening end of said battery case is bent so as to wrap the upper end of the outer peripheral cylindrical portion of said sealing body, and the bent portion is crimped inward to fasten the flange of said first negative terminal plate, the flange of said second negative terminal plate, and said insulation plate, wherein said first negative terminal plate and said second negative terminal plate have a substantially identical shape, the boundary portion of said first negative terminal plate and the boundary portion of said second negative terminal plate each have a hole for discharging a gas out of said battery, and are spaced 0.2 to 1 mm apart.