An electric vehicle (EV) refers to any vehicle that is propelled in part or solely by an electric motor. A plug-in hybrid electric vehicle (PHEV) is a type of EV which is propelled by both a fuel internal combustion engine (ICE) as well as an electric motor. It can be charged by plugging in but also has an internal combustion engine that runs on liquid fuel. This helps to either propel the vehicle or powers the battery as a generator. Fuel supplements the battery as a power source, effectively extending the range. Some PHEV models only use fuel when the battery is depleted.