A battery pack control apparatus for a battery pack that includes a
plurality of unit cells electrically connected in series prevents
overdischarging based on the total voltage of the battery pack, as
opposed to being based on the separate voltages of the individual unit
cells. When a total voltage of the battery pack corresponds to a lowest
voltage of one of the plurality of unit cells decreasing to a
predetermined threshold at which overdischarging would begin to occur,
power supply to a load from the battery pack is at least partially
restricted.