Abstract: A rechargeable battery that includes: an electrode assembly generating a current; a case accommodating the electrode assembly therein; and a cap assembly coupled to the case so as to be electrically connected with the electrode assembly. The electrode assembly includes a first electrode, a separator, and a second electrode that are sequentially stacked, and the separator includes a main body part disposed between the first and second electrodes and protrusions formed that protrude from the main body part to the side of at least one of an end portion of the first electrode and an end portion of the second electrode.