  Drive modes are driver-selectable pre-set configurations of powertrain and
certain vehicle parameters. Plug-in hybrid electric vehicles (PHEVs) typically
feature special options of drive modes that can affect the hybrid energy source
management system, for example, electric vehicle (EV) mode (that draws fully on
battery) and charge sustaining (CS) mode (that utilizes internal combustion
engine to charge battery while propelling the vehicle). This paper studies an
optimization problem to enable the driver to select the appropriate drive modes
for fuel minimization. We develop optimization algorithms that optimize the
decisions of drive modes based on trip information, and integrated with path
planning to find an optimal path, considering intermediate filling and charging
stations. We further provide an online algorithm that is based on the revealed
trip information. We evaluate our algorithms empirically on a Chevrolet Volt,
which shows significant fuel savings.
