The secondary battery includes a body part provided in a pillar shape on an outer wall and including a passage, through which the electrolyte flows, therein, a pin switch extending in a longitudinal direction of the body part, wherein, when a pressure is applied to an end of the pin switch, the pin switch linearly moves toward the inside, and when the pressure is removed, the pin switch linearly moves toward the outside, a manipulation part to move in a direction that is parallel to the pin switch, a pressure apply part protruding from a central portion of the manipulation part to apply a pressure an end of the pin switch, and a switching part disposed on the other end of the pin switch to open and close the passage.