The present invention relates to a battery pack having an amorphous structure, and more specifically provides a battery pack in which an electrode assembly built in inside a battery case comprises a positive electrode, a negative electrode, and a separation film which is interposed between the positive electrode and the negative electrode, and a positive electrode terminal and a negative electrode terminal protrude from an end portion of an outer circumferential surface on a first side from a planar view, and an outer circumferential surface on a second side that is opposite the first side outer circumferential surface is formed as a curved surface.