US Patent 10153636 Electric vehicle hybrid battery system

An electrically-powered vehicle comprising a hybrid battery system is disclosed. The vehicle comprises a motor and a hybrid battery system coupled to the motor. The hybrid battery system comprises a first battery of a first energy density and a first power density and a second battery in parallel with the first battery. The second battery has a second energy density lower than the first energy density and a second power density greater than the first power density. The vehicle is configured to draw power disproportionally from the first battery in a first mode and disproportionally from the second battery in a second mode.