Under the hood of hybrid vehicles

摘要

Energy- and emission-efficient automobiles are increasingly relying on both combustion engines and electric motors for cower. The term "hybrid automobile" has held a number of meanings. An early use in the United States meant a vehicle of mixed national origins. Today, the term refers to vehicles that derive their propulsion from more than one type of power source. Hybrids are also vehicles that can use a mixture of multiple types of fuel, such as gasoline and ethanol-alcohol fuel. For this article, a hybrid vehicle is one that combines an internal combustion engine with electric batteries powering electric motors to provide force to the vehicle's wheels.