High frequency power supplied to the primary coil from the high frequency power supply is transferred to the secondary coil by magnetic induction, and secondary coil AC is rectified to charge the battery pack housed in the portable electronic equipment. The battery charger is provided with internal batteries that are charged by input power and supply power to the high frequency power supply, and with a charging circuit to charge the internal batteries. The external case is provided with storage space between its top plate and bottom plate, and internal batteries, which are rectangular batteries, and a planar primary coil wound in a spiral shape are disposed in that storage space. The battery charger charges the internal batteries with input power, and when no power is input, internal battery power is converted to high frequency power and supplied to the primary coil to charge the battery pack.