A battery includes an electrode assembly, the electrode assembly including a positive electrode, a negative electrode, and a separator interposed between the positive electrode and the negative electrode, a current collector, the current collector being electrically and mechanically coupled to one of the electrodes, a case, the electrode assembly and the current collector being disposed within the case, a cap plate, the cap plate having a terminal protruding therefrom, the terminal being electrically coupled to the current collector, and a separating member, the separating member having a protrusion portion and a body portion, the protrusion portion being fixed to the cap plate, and the body portion extending along a length of the current collector and being interposed between the current collector and an inner wall of the case.