SECONDARY BATTERY, BATTERY PACK, AND AUTOMOBILE

A secondary battery includes an electrode assembly having a first electrode tab and a second electrode tab, a battery can electrically connected to the second electrode tab and having an opening portion accommodating the electrode assembly, a top cap covering the opening portion of the battery can and electrically connected to the first electrode tab, a conductive washer electrically connected to the battery can and adjoining a peripheral portion of the opening portion, and an insulative member provided between the top cap and the battery can and the conductive washer electrically connected to the battery can, the insulative member being configured to electrically insulate the top cap and at least one of the battery can and the conductive washer. The top cap includes first and second surfaces facing each other, the second surface having a protruding portion exposed through a hole formed in a central portion of the conductive washer.