ELECTRONIC DEVICE, ELECTRONIC SYSTEM, AND METHOD FOR SWITCHING BATTERY USED IN ELECTRONIC DEVICE

In electronic device () of the present disclosure, control circuit () selects one of first battery () and second battery () of extension device (), and causes selected one to supply electric power to a load circuit. Control circuit () detects which state of switch () is in a first state or a second state. Control circuit () preferentially selects first battery () as a supply source of electric power to the load circuit as compared with second battery () when switch () is in the first state.