A Range-Extender vehicle is a battery electric vehicle that includes an additional power source such as a small petrol or diesel engine known as a ‘Range-Extender’. This supplementary engine drives an electric generator that tops-up a battery which in turn, supplies the vehicle’s electric motor with electricity. Unlike a Plug-In Hybrid the engine does not directly provide power to the wheels of the vehicle. Typically, such vehicles can travel up to 150 miles on a single charge.
The London Electric Vehicle Company electric taxi is an example of a range extended vehicle which switches automatically between using its lithium-ion battery and a petrol-powered range extender.