Patent ID: 9688224
Date: 2017-06-27
CPC Classifications: B60R,F02N

Claim:
1. A vehicle electric power supply apparatus mounted in a vehicle, the vehicle being provided with an internal combustion engine and an operation switch which is used to output a signal that commands starting and stopping of the internal combustion engine corresponding to an operation of an operator, the apparatus comprising: a first power source; a second power source that is connected in parallel to the first power source; a DC-DC converter that is connected between the first power source and the second power source; a resistance and a rectifier that are connected between the first power source and the second power source, the rectifier being provided such that a current flows in a direction from the first power source to the second power source; a switch that is connected in parallel to the DC-DC converter and is connected between the first power source and the second power source; an opening and closing unit that is used to open and close the switch; and a control unit that controls the DC-DC converter and the opening and closing unit, wherein, when the internal combustion engine is stopped corresponding to the signal that is output from the operation switch, the control unit sets the switch to be OFF using the opening and closing unit, and the control unit causes the second power source to be discharged and the first power source to be charged until an output voltage of the second power source reaches a first voltage that is less than a voltage of the first power source, and prevents the output voltage of the second power source from decreasing to less than a minimum safeguard voltage, by electric power supply from the second power source to the first power source via the DC-DC converter.