A secondary battery including an electrode assembly, the electrode assembly including a separator between a positive electrode and a negative electrode; current collectors, the current collectors being electrically connected to the positive electrode and the negative electrode, respectively; a case, the case accommodating the electrode assembly and the current collectors; a cap plate, the cap plate coupled to an opening in the case; and an insulating film between the current collectors and the case, the insulating film including a recess corresponding to a shape of at least one of the current collectors and the electrode assembly to offset a vibration of the current collectors with respect to the case.