A cell has: a pole terminal placed on outside of a cell case; a deformed terminal fixing the pole terminal to the case by a base surface portion and a protruding portion; an inversion plate attached to the base surface portion and interrupting conduction between the internal terminal and the deformed terminal by inversion deforming away from the internal terminal at least at a portion when the internal pressure of the case increases beyond working pressure; and a shaft member having at least a part of the top portion placed in the protruding portion, and reestablishing conduction between the internal terminal and the deformed terminal after the inversion plate inverted by the top portion being pressed from the outside and thereby being moved inside the protruding section to press the inversion plate inward. A sealed space is provided between the deformed terminal and the inversion plate.