A rechargeable battery is provided. The rechargeable battery includes a case, an electrode assembly in the case, a cap plate sealing an opening of the case, and a terminal portion attached to the cap plate. The terminal portion includes a terminal plate on the cap plate and electrically connected to the electrode assembly, and an auxiliary plate electrically connecting the cap plate to the terminal plate. The auxiliary plate has a plurality of openings for reducing a current flow along a short circuit current path.