An aspect of the present invention provides a rechargeable battery which makes placement of the electrode assembly in the case during assembly easy. The rechargeable battery includes an electrode assembly including a first electrode, a separator, and a second electrode, a case housing the electrode assembly and having an opening in a plane parallel to a flat side surface of the electrode assembly, the case being electrically connected to the first electrode, a cover closing the opening in the case, and an electrode terminal mounted to a terminal opening in the case and connected to the second electrode, wherein the electrode terminal and the second electrode are insulated from the case.