A vehicle power unit charges a first and second capacitor when a starter cannot be used, or supplies battery power to the starter when the control circuit operates the starter and the total voltage of the first and second capacitor is less than a default total voltage. When the starter is operated and the total voltage is equal to or greater than the default total voltage, a parallel circuit is created with the battery and the first capacitor and this parallel circuit is connected in series to the second capacitor to operate as the vehicle is started up. Also, the battery is disconnected from the starter during use of the vehicle when the starter is operated and the total voltage is equal to or greater than the default total voltage. This vehicle power unit can reduce the load on the battery when the starter is operated and extend the life of the battery.
