Abstract: In a battery pack in which a protective circuit is fitted to a unit cell and accommodated in an exterior cover, a frame is provided in the exterior cover, the frame being fixed to the unit cell and supporting the protective circuit, where a protruding portion protruded from the frame and an engaging hole provided in the unit cell are engaged with each other. As a result of this, when external force acts on the exterior cover, movement of the frame integrated with the exterior cover can be inhibited.

Abstract: In a battery pack in which accessory parts are fitted to a unit cell, the unit cell has a terminal portion, accessory parts include an electrical-connection use lead and a frame having an engagement portion to be engaged with the lead, and the lead and the terminal portion are bonded together by welding while the lead is engaged with the engagement portion. As a result of this, movement of the frame can be inhibited under action of external force. Moreover, in a structure in which an exterior cover is fitted to the frame or in which resin mold is integrally molded with the frame, movement of these members can be inhibited when external force acts on the exterior cover or the resin mold.

Abstract: A battery package including a battery having at least one flat mount face defined therein, an electric circuit device for controlling discharging and charging of the battery, and a generally plate-like protective member mounted on the battery so as to cover the electric circuit device. The electric circuit device is made up of a plurality of circuit component parts and is mounted on the flat mount face with the circuit component parts held in tight contact with the flat mount face. The protective member includes an oblong plate member and side flanges protruding transversely from opposite side edges of the plate member to define a cavity. In an assembled condition with the protective member fitted to the battery, the electric component parts are accommodated within the cavity.