A secondary battery including an electrode assembly, the electrode assembly including electrode plates and a separator interposed between the electrode plates, at least one of the electrode plates including a coated part, the coated part including a metallic plate having an active material coated thereon, and an uncoated part, the uncoated part including a metallic plate without active material coated thereon, the uncoated part including a folding line in the uncoated part, and a folding part with an end portion folded with respect to the folding line; and a current collector electrically contacting the folding part.