Reservation system, navigation device, battery charger and server

Reservation system realizing more efficient reservation of charging. The reservation system comprises a navigation device and a battery charger. The navigation device generates reservation information of a charge, and sends the reservation information to the battery charger. The battery charger makes a schedule by using the reservation information, and performs charging according to the schedule. Further, the battery charger makes again a schedule according to an arrival time of a booked vehicle.