Abstract: According to one embodiment, a storage battery device includes a battery group, a charge-and-discharge control FET unit, and a drive controller. The battery group includes a plurality of battery cells connected in series. The charge-and-discharge control FET unit is connected to a low potential side of the battery group and includes at least a pair of N-channel MOSFETs source terminals of which are back-to-back connected. The drive controller outputs a drive control signal to a gate terminal of the respective N-channel MOSFETs included in the charge-and-discharge control FET unit. The drive control signal is generated based on a potential level of the source terminals.