A sealing structure for a battery includes a plate shaped member having a through hole, a polymer molding, and an electrode. The polymer molding has a tube portion provided along an entire edge of the through hole and a base portion provided on the tube portion. The electrode has a column portion disposed on an inner periphery of the tube portion and a plate portion provided on the column portion. A back surface of the plate shaped member contacts a front surface of the base portion. A front surface of the plate portion contacts a back surface of the base portion. The back surface of the plate shaped member has an annular first projection provided around the through hole and projecting toward the base portion. The front surface of the plate portion has an annular second projection provided around the through hole and projecting toward the base portion.