Electric storage apparatus

A BMS (13) is configured to switch a state of a relay (12) from a closed state to an open state if a controller (22) determines that a cell voltage of a cell (C) of an assembled battery (11) is equal to or lower than a power-saving threshold. With this configuration, power of an electric storage device is less likely to be consumed by an electric load. The BMS (13) is further configured to switch a power consumption mode of the BMS (13) from a sleep mode to a deep sleep mode if the controller (22) determines that the cell voltage is equal to or lower than the power-saving threshold. The BMS (13) in the deep sleep mode consumes less power than the BMS (13) in the sleep mode. With this configuration, the BMS (13) consumes less power of the assembled battery (11).