CYLINDRICAL BATTERY

Provided is a cylindrical battery with which it is possible to suppress an increase in weight while increasing capacity. A cylindrical battery (10) includes: an electrode body comprising a positive electrode and a negative electrode, which are wound together via a separator; an electrolyte; a bottomed cylindrical outer can (20) for accommodating the electrode body and the electrolyte; and a sealing body (30) that is fixed to an open end portion (20B) of the outer can (20) by swaging and is for sealing the outer can (20). In regard to the outer can (20), the outer diameter of a body part (20A) for accommodating the electrode body is 20 mm or greater, and the outer diameter of the open end portion (20B) for accommodating the sealing body (30) is less than the outer diameter of the body part (20A).