POWER SUPPLY APPARATUS

A power supply device for supplying power to a load by combining a secondary battery and a capacitor connected in parallel to the secondary battery includes an insulation type DC-DC converter with a primary coil connected in parallel to the secondary battery and configured to accumulate energy by a current supplied from the secondary battery and a secondary coil connected in series to the capacitor and configured such that an induction current flows therein by the accumulated energy from the primary coil.