Battery charge state transmission device and external charging system

摘要

A communication part of a battery charge state transmission device of a charging device acquires charge state information of each external charge vehicle. A station communication part transmits the charge state information to an information management station device. The charge state information is grouped for transmission so that the number of transmissions, the amount of communication traffic and the cost of communication with the management station device, and the operation load of the management station device are reduced.