A vehicle includes an electric motor and a battery operable to provide electrical power to the electric motor. The battery system includes a first battery pack and a second battery pack. The first battery pack has a relatively high power density, and the second battery pack has a relatively high energy density. An electronic controller determines a remaining driving range of the first battery pack, and a remaining driving range of the second battery pack. The vehicle has a human-machine interface (HMI) operatively connected to the electronic controller and configured to indicate the remaining driving range of the first battery pack and the remaining driving range of the second battery pack. The controller executes a method of monitoring the battery system.