Battery

In a battery, a terminal member includes: a columnar portion; a head portion, outside an outer casing, having a larger diameter than a through hole of a lid; and an umbrella-shaped portion, more inside than a current collecting member, having a larger diameter than a through hole of the current collecting member to closely contact an inside surface thereof. A gasket includes: a plate-shaped portion between the lid and the head portion; and a cylindrical portion between a wall surface of the through hole of the lid and the columnar portion. An insulator includes: a plate-shaped portion between the lid and the current collecting member; and a cylindrical portion between the wall surface of the through hole of the lid and the columnar portion. Leading ends of the cylindrical portions close contact each other between the wall surface of the through hole of the lid and the columnar portion.