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Inspection of cell internal resistance (Rint) derived by the hybrid pulse power characterization (HPPC) tests indicates that Rint is a function of relative capacity (state of charge, or SOC), thus some SOC ranges are more efficient than others. Therefore energy losses can be minimized by placing charge sustaining operation in a more efficient SOC range. This creates three operational stages; the initial charge depleting stage to an efficient SOC, a charge sustaining stage until a recharge station is within reach, and a final charge depleting stage until arrival. When coupled with a known drive distance, this three segment Internal Resistance Based (IRB) control strategy increases the extended range electric vehicle (EREV) net battery efficiency from 96.8 to 97.3 % with an associated 14 % decrease in energy losses across the urban domestic drive schedule.