This most commonly refers to gasoline - electric hybrid vehicles, which use gasoline (petrol) and electric batteries for the energy used to power internal - combustion engines and electric motors. (sciencedaily.com)
This would make the cars lighter — important because of the weight of electric batteries — but also allowing for more inventive designs. (cnbc.com)
The front diesel motor generates the major power source, while the two independent rear electric battery powered motors kick in at lower speeds while helping with the fuel economy. (gtchannel.com)