Patent ID: 9387763
Filing Date: 2016-07-12
CPC Classification: B60L,Y02T

Claim Text:
1. A power source device for a vehicle that includes a driving motor and an electric load mounted on the vehicle, the power source device comprising: a first battery that supplies power to the driving motor of the vehicle, the first battery including a cathode; a switch that is connected between the cathode terminal of the first battery and the driving motor, the switch including a terminal at a side of the driving motor; a controller that controls on and off operations of the switch; a second battery that supplies power to the electric load mounted in the vehicle, the second battery including a cathode terminal; a step-down circuit that is connected between: (i) the terminal of the switch, and (ii) the cathode terminal of the second battery, steps down an output voltage of the first battery, and provides the stepped-down voltage to the cathode terminal of the second battery, the step-down circuit including a connecting node; a first power source circuit that supplies power to the controller; a second power source circuit that supplies power to the step-down circuit, the first and second power source circuits being supplied with power from the second battery and including a connecting node; a diode that is connected, in a forward direction, between: (i) the connecting node of the step-down circuit and the second battery, and (ii) the connecting node of the first and second power source circuits, the diode including a cathode; and a third battery having a cathode terminal connected to the cathode of the diode via a charging circuit and a discharging circuit for charging and discharging the third battery.