An electric storage device management apparatus for monitoring an electric storage device assembly charged and discharged by a charger/discharger, the electric storage device assembly including a plurality of electric storage devices connected in series, the electric storage device management apparatus comprising: a voltmeter configured to measure voltages of the electric storage devices, respectively; a discharging circuit provided separately from the charger/discharger and configured to discharge the electric storage devices individually; and a controller configured to: control the discharging circuit to discharge one of the electric storage devices such that the states of charge of the electric storage devices are equalized; characterized in that the controller is further configured to: determine whether a first variation in voltage per predetermined time period of a first electric storage device of the electric storage devices has increased to a reference value, and whether a second variation in voltage per predetermined time period of a second electric storage device of the electric storage devices has increased to the reference value; measure an elapsed time period (ΔT1) from when the first variation in voltage per predetermined time period of the first electric storage device has increased to the reference value to when the second variation in voltage per predetermined time period of the second electric storage device of the electric storage devices has increased to the reference value; control the discharging circuit to discharge the one of the electric storage devices for a discharging time period that is based on the elapsed time period (ΔT1). a voltmeter configured to measure voltages of the electric storage devices, respectively; a discharging circuit provided separately from the charger/discharger and configured to discharge the electric storage devices individually; and a controller configured to: control the discharging circuit to discharge one of the electric storage devices such that the states of charge of the electric storage devices are equalized; characterized in that the controller is further configured to: determine whether a first variation in voltage per predetermined time period of a first electric storage device of the electric storage devices has increased to a reference value, and whether a second variation in voltage per predetermined time period of a second electric storage device of the electric storage devices has increased to the reference value; measure an elapsed time period (ΔT1) from when the first variation in voltage per predetermined time period of the first electric storage device has increased to the reference value to when the second variation in voltage per predetermined time period of the second electric storage device of the electric storage devices has increased to the reference value; control the discharging circuit to discharge one of the electric storage devices such that the states of charge of the electric storage devices are equalized; characterized in that the controller is further configured to: determine whether a first variation in voltage per predetermined time period of a first electric storage device of the electric storage devices has increased to a reference value, and whether a second variation in voltage per predetermined time period of a second electric storage device of the electric storage devices has increased to the reference value; measure an elapsed time period (ΔT1) from when the first variation in voltage per predetermined time period of the first electric storage device has increased to the reference value to when the second variation in voltage per predetermined time period of the second electric storage device of the electric storage devices has increased to the reference value; control the discharging circuit to discharge the one of the electric storage devices for a discharging time period that is based on the elapsed time period (ΔT1).