Secondary battery

A secondary battery comprising:

• a battery device including a first electrode, a second electrode, and an electrolytic solution;
• a container member containing the battery device;
• and
• a safety valve mechanism attached to an end part of the container member in a height direction of the container member, wherein
• the safety valve mechanism includes
• a valve member having an electrically conductive property, the valve member including a valve part and an annular protruding part, the valve part being electrically coupled to the first electrode and cleavable, the annular protruding part surrounding the valve part along a horizontal plane, the horizontal plane being orthogonal to the height direction,
• an insulating holder surrounding the annular protruding part along the horizontal plane, and
• an electrically conductive member including a hook member including a hook, the hook being opposed to the annular protruding part with the insulating holder interposed between the hook and the annular protruding part, the electrically conductive member occupying an entire region that overlaps the insulating holder in the height direction.