Cars are responsible for around 12% of total EU emissions of carbon dioxide (CO2), the main greenhouse gas. For this reason the growing concern about environmental pollution, climate change and global warming is shifting the attention of the transportation sector towards the development of technologies not dependent on fossil fuels. In particular, for passenger cars, BEVs (Battery Electric Vehicles) and HEVs (Hybrid Electric Vehicles) are expected to gain a greater importance on the market in the upcoming years, especially in the European Union where new regulations will be phased in from 2020, decreasing the emission limit of the main greenhouse gas, carbon dioxide, from 130 gCO2/km to 95 gCO2/km for the fleet average of car manufacturers.