NOVELTY - A battery pack, comprises package body having first area in which housing recessed part for housing battery element (2) is formed, second area formed continuously to first area, and third area provided continuously to second area to be perpendicular to first area; frame in which battery element is housed; and connecting board disposed in frame to which terminals are connected and having terminal part electrically connected to external device.    USE - For information device, such as notebook type personal computer, mobile communication device e.g. portable telephone, and portable electronic device e.g. video camera.    ADVANTAGE - The increase volume of the battery pack is decreased as much as possible without deteriorating a mechanical strength and the reliability of terminals.    DETAILED DESCRIPTION - A battery pack, comprises:    (1) a battery element having a cathode, an anode and polymer electrolyte, terminals being drawn from the cathode and the anode, respectively;    (2) a package body having a first area (51) in which a housing recessed part for housing the battery element is formed, a second area (52) formed continuously to the first area, and a third area (53) provided continuously to the second area to be perpendicular to the first area;    (3) a frame disposed in the periphery of the housing recessed part in which the battery element is housed; and    (4) a connecting board disposed in the frame to which the terminals are connected and having a terminal part electrically connected to an external device.    The battery element is housed in the recessed part. The second area is located in a side opposite to a side from which the terminals of the housed battery element are to drawn is bent relative to the first area to cover a first surface of the battery element exposed outside and unite the first area to the second area. The terminals of the battery element housed in the housing recessed part and covered with the second area are connected to the connecting board. The frame is disposed in the periphery of the housing recessed part in which the battery element is housed. The connecting board is disposed in the frame. The third area of the package body is bent relative to the second area. A second surface side opposite to the first surface of the battery element housed in the housing recessed part of the first area and covered with the first area and the second area is covered with the third area and the third area is united to the first area. An INDEPENDENT CLAIM is also included for production of a battery pack comprising:    (1) housing a battery element having a cathode, an anode and polymer electrolyte, terminals being drawn from the cathode and the anode, respectively in a housing recessed part of a package body having a first area in which the housing recessed part for housing the battery element is formed, a second area formed continuously to the first area and a third area so provided continuously to the second area so as to be perpendicular to the first area;    (2) bending the second area located in a side opposite to a side from which the terminals of the battery element housed in the housing recessed part are drawn relative to the first area to cover a first surface of the battery element exposed outside and uniting the first area to the second area;    (3) connecting the terminals of the battery element housed in the housing recessed part and covered with the second area to a connecting board having a terminal part electrically connected to an external device; and providing a frame in the periphery of the housing recessed part in which the battery element is housed and disposing the connecting board in the frame;    (4) bending the third area of the package body relative to the second area and covering a second surface side of the battery element housed in the housing recessed part of the first area and covered with the first area and the second area with the third area; and    (5) uniting third area to the first area.    DESCRIPTION OF DRAWING(S) - The figure is a sectional view of a battery pack.    Battery element (2)    Front wall part (4a)    Rear wall part (4b)    Cathode terminal (21)    First area (51)    Second area (52)    Third area (53)