Patent ID: 7338733

Claim:
A battery pack comprising: an external case; and a thin outline battery held in the external case, the battery having a thickness that is smaller than its width; wherein the external case is provided with openings which expose a front surface and a back surface of the thin outline battery to the outside, the external case is formed in the shape of a rectangular frame which covers both sides and both ends of the thin outline, and the thickness of the external case is substantially equal to the thickness of the thin outline battery or the external case is thinner than the thin outline battery, wherein the external case comprises a first case section and a second case section divided between the front and back surfaces of the thin outline battery, each of the first case section and the second case section comprising side wall case sections and end region case sections, respectively, such that the first case section and the second case section hold the thin outline battery by connecting side wall case sections and end region case sections, respectively, and wherein the thin outline battery has first curved surfaces at both side walls, the first curved surfaces of the side walls defining rounded corner edges and central protruding regions, the side wall case sections have second curved surfaces which at least partially complement the first curved surfaces, the edges of the side wall case sections being positioned at the rounded corner edges of the thin outline battery to mate the edges of the side wall case sections with the rounded corner edges of the thin outline battery by contacting the first curved surfaces of the side walls with the second curved surfaces of the side wall case sections such that the external case holds both sides of the thin outline battery with the side wall case sections thereby preventing the thin outline battery from falling out in the front or back directions of the thin outline battery.