Battery management system and method of driving the same

A battery management system (BMS) and a method of driving the same are disclosed. In one aspect, the BMS includes a first state of charge (SOC) estimator configured to estimate an SOC of a battery using at least one of i) a charge and discharge current of the battery, ii) a voltage of the battery and iii) a temperature of the battery. The BMS also includes a residual capacity estimator, when the estimated SOC is substantially equal to or less than the reference SOC, configured to estimate a current residual capacity using at least one of i) a reference residual capacity calculated from a reference SOC, ii) the measured battery voltage, iii) a first reference voltage, and iv) a second reference voltage. The BMS further includes a second SOC estimator configured to estimate a current SOC based at least in part on the current residual capacity.