RECHARGEABLE BATTERY

An aspect of the present invention is to provide a rechargeable battery that implements a high output of an electrode assembly by reducing electrical resistance at a connection portion of a uncoated portion and a lead tab. A rechargeable battery according to an embodiment of the present invention includes: an electrode assembly wound by arranging a separator between electrodes; a lead tab connected to the electrode; and a case which accommodates the electrode assembly and of which the lead tab is drawn to the outside, and the lead tab includes a first tab formed with a first width and a first thickness and connected to an uncoated portion of the electrode, and a second tab formed with a second width equal to or less than the first width and a second thickness equal to or more than the first thickness, and connected to the first tab.