PROBLEM TO BE SOLVED: To eliminate radiation countermeasures and to prevent taking-out from a secondary battery.SOLUTION: A power path switching method is a method for switching a first power path from the secondary battery incorporated in a communication apparatus and a second power path from a charger for charging the secondary battery, which can be connected to the communication apparatus by insertion/extraction. In the power path switching method, a load of the communication apparatus is divided into two systems of a first load and a second load. Power is supplied to the first load from the first power path. While the secondary battery is charged by the charger, power is supplied to the second load from the second power path. While the secondary battery is not charged, power is supplied from the first power path.