Power supply provided with battery unit

A current is cut off by reliably fusing a fuse element of an SCP with a simple circuit configuration. A power supply provided with a battery cell performs ON/OFF control by a control circuit (7) on a switch (6) that connects an SCP3, which is connected in series with the battery cell (1) and cuts off a charge/discharge current in an abnormal state, to the battery cell (1). The battery cell (1) is provided with a plurality of unit cells (2) connected in series, the SCP3 is provided with a fuse element (4) connected in series to the output side of the battery cell (1) and a heater (5) for fusing the fuse element (4), and the switch (6) is provided with a plurality of switching elements (10) having one terminal connected to the heater (5) and the other terminal connected to different voltage terminals (11) of the battery cell (1). The control circuit (7) selects, by means of a selection circuit (9), a switching element (10) that is switched to an ON state by means of the voltage detected by the voltage detection