Patent ID: 7556885

Claim:
A battery pack comprising a battery element of polymer battery, wherein the battery element is contained in a concave portion formed in a soft laminate material and is covered with a hard outer covering material such that the battery element is placed on the hard outer covering material in an opened state, and the hard outer covering material is closed where both ends of the hard outer covering material are bonded together, each of the soft laminate material and the hard outer covering material is a multi-layer film structure; and the battery pack is shaped so as to have a substantially semicircular form in cross-section in which both sidewalls expand outwards, wherein the battery pack further includes a top cover and a rear cover made of a resin that are inserted into a respective side of an edge face of the battery element wherein the soft laminate material includes a soft metal layer composed of annealed aluminum at a thickness ranging from about 30 μm to about 130 μm, and wherein the hard outer covering material includes a hard metal layer composed of unannealed aluminum at a thickness ranging from about 30 μm to about 130 μm.