In order to be able to drive longer distances on emissionfree electric power, the hybrid vehicle is provided with a more powerful lithium-ion battery. This can be charged before the trip straight from a mains socket by means of a battery charger. Hence the designation of the vehicle as a “plug-in hybrid”.

By comparison with an internal-combustion engine, the plug-in hybrid reduces both fuel consumption and CO₂ output by an average of 50%.