In the recent years there has been an increasing investment by car manufacturers in the production of electric and hybrid electric vehicles. The reason for this sudden change can be associated with the stringent environmental constraints imposed by government regulations. The consequence is that many researches are now focusing on the employment of new strategies to keep up with these restrictions. These studies develop technologies both at vehicle-level (control strategies) and subsystem-level (powertrain and energy storage components). An important component to manage the power supply of Electric Vehicles (EVs) and Hybrid Electric Vehicles (HEVs) is the Energy Storage System (ESS). Batteries are the most common ESS component thanks to their energy density, compact size and reliability.