A rechargeable battery includes an electrode assembly; a case having a sealing portion surrounding the electrode assembly; and a lead electrically connected to the electrode assembly and extending in a first direction, wherein the lead includes a first region in contact with the electrode assembly and located inside the case; a second region exposed to an outside of the case; and a third region located between the first region and the second region and overlapping the sealing portion of the case, wherein the third region has a width greater than that of the first region and the second region in a second direction and has a thickness smaller than that of the first region and the second region in a third direction, and wherein the second direction is perpendicular to the first direction, and the third direction is perpendicular to the first direction and the second direction.