NOVELTY - The device (100) has a fastening unit (5) that is extended in lamination direction of battery cell (1) for fastening end plates (3) and is provided with element for heat dissipation. A bottom-covered armored can is opened at surface to obstruct opening of can by sealing board. An internal electrode with pair of output terminal protruded from surface of board is accommodated in can and is connected by internal electrode connection unit. Bottom face of battery laminated structure (2) is contacted with fixing device portion by bottom heat sinking plane for heat-exchange.    USE - Power supply device for motor in electric vehicle such as hybrid vehicle e.g. plug-in type hybrid electric vehicle, fuel cell electric vehicle and electrically-driven motorcycle, and electrical storage apparatus in heavy currents for household use and electrical storage use for factory (all claimed).    ADVANTAGE - Since the bottom face of battery laminated structure is contacted with fixing device portion by bottom heat sinking plane for heat-exchange, the cooling of device portion can be efficiently calculated by heightening the cooling capacity of cooling plate. The thermal radiation performance in the upper surface of battery cell and heat dissipation in the surface can be effectively improved. The temperature dispersion in the height direction of battery cell can be reduced, such that the lifetime improvement of a battery cell can be exhibited. The increase of mechanical strength can be raised and reliability with fastening a battery laminated structure can be improved with simplified structure and reduced cost. The firmer connection intensity can be realized, so that the set screws can be protected and the enlargement of a power supply device can be suppressed.    DETAILED DESCRIPTION - INDEPENDENT CLAIMS are included for the following:    (1) an electric vehicle; and    (2) an electrical storage apparatus.    DESCRIPTION OF DRAWING(S) - The drawing shows a top view of the power supply device.    Battery cell (1)    Battery laminated structure (2)    Fastening end plate (3)    Fastening unit (5)    Power supply device (100)