A battery device comprising: a battery; a charging and discharging switch unit configured to control charging and discharging of the battery and comprising a first switch and a second switch provided in a current path between the battery and a load or an external power source, wherein the first switch comprises a first FET in parallel with a first parasitic diode, the first parasitic diode placed in a direction so as to interrupt current from the battery and the second switch comprises a second FET in parallel with a second parasitic diode, the second parasitic diode placed in a direction so as to interrupt current towards the battery; a pre-charging unit comprising at least one capacitor (Cs) that is installed between a terminal of the battery and the gate terminal of the first FET, and that is configured to be charged during discharging of the battery; and a discharging unit configured to discharge the charge charged in the at least one capacitor of the pre-charging unit during turning off of the charging and discharging switch unit, a driving unit configured to control the first switch and the second switch, wherein the driving unit comprises: a state detection unit configured to detect the state of the battery; a control unit configured to generate a control signal for driving the charging and discharging switch unit using detected data of the state detection unit; and a signal output unit (431,432) configured to output the control signal to the respective gates of the first and second FET of the charging and discharging switch unit, wherein the discharging unit comprises a third diode provided between the pre-charging unit and the driving unit placed in a direction so as to interrupt current from the driving unit to the at least one capacitor. a battery; a charging and discharging switch unit configured to control charging and discharging of the battery and comprising a first switch and a second switch provided in a current path between the battery and a load or an external power source, wherein the first switch comprises a first FET in parallel with a first parasitic diode, the first parasitic diode placed in a direction so as to interrupt current from the battery and the second switch comprises a second FET in parallel with a second parasitic diode, the second parasitic diode placed in a direction so as to interrupt current towards the battery; a pre-charging unit comprising at least one capacitor (Cs) that is installed between a terminal of the battery and the gate terminal of the first FET, and that is configured to be charged during discharging of the battery; and a discharging unit configured to discharge the charge charged in the at least one capacitor of the pre-charging unit during turning off of the charging and discharging switch unit, a driving unit configured to control the first switch and the second switch, wherein the driving unit comprises: a state detection unit configured to detect the state of the battery; a control unit configured to generate a control signal for driving the charging and discharging switch unit using detected data of the state detection unit; and a signal output unit (431,432) configured to output the control signal to the respective gates of the first and second FET of the charging and discharging switch unit, wherein the discharging unit comprises a third diode provided between the pre-charging unit and the driving unit placed in a direction so as to interrupt current from the driving unit to the at least one capacitor. a state detection unit configured to detect the state of the battery; a control unit configured to generate a control signal for driving the charging and discharging switch unit using detected data of the state detection unit; and a signal output unit (431,432) configured to output the control signal to the respective gates of the first and second FET of the charging and discharging switch unit, wherein the discharging unit comprises a third diode provided between the pre-charging unit and the driving unit placed in a direction so as to interrupt current from the driving unit to the at least one capacitor.