A battery capable of preventing deformation thereof when gas is generated is provided. In the battery, a safety valve is electrically connected to a battery element, and an insulating plate is arranged between the battery element and the safety valve. The safety valve has a plurality of vent holes around a central portion thereof. The insulating plate has seven or more openings in the circumferential direction in a position where the openings can face to the vent holes of the safety valves around a central portion thereof.