Abstract: A management server, which is a temperature-monitoring device, monitors the temperature of a battery that is removably attached to an apparatus. The management server includes: a server-side acquisition unit that acquires the temperature of the battery when the battery is not in use after discharging electricity to the apparatus; and a determination process unit that performs a temperature determination process for determining whether or not the temperature while the battery is not in use is in a predetermined temperature range. The determination process unit excludes, from items on which the temperature determination process is to be performed, the temperature during an initial period from when the non-use of the battery has started to when a predetermined condition is satisfied.

Abstract: A management system includes a management server that can communicate information with a battery station that houses a battery that is lent based on a usage agreement. The management server acquires the lending date and time at which the battery is lent from the battery station, and the return date and time at which the battery is returned to the battery station during the usage agreement period of an existing contract user. When a prescribed period has elapsed from the lending date and time without the battery being returned, or when a prescribed period has elapsed from the return date and time without the battery being lent, the management server determines that the battery is in an idle state.