BMW Concept 5 Series ActiveHybrid

BMW's 5 Series ActiveHybrid uses a twin-turbo 3-liter straight-six-cylinder engine, similar to that found in the 535i. The addition of a 40-kilowatt motor and lithium ion battery pack gives the car 10 percent better fuel economy and fewer emissions than its gas-only equivalent. In situations such as heavy traffic, the hybrid system can shut off the engine and drive the car under electric power.