Publisher Summary The starting point of power sources for electric vehicles is the lead-acid battery. Because of their relatively low power density, compared with other types of battery which are available, other types of batteries are alsoconsidered for this application. The low power density of the lead-acid system puts severe limitations on the range that can be achieved between battery charges, although the restrictions regarding acceleration and maximum speed are not as limiting as they once were. The lead-acid battery is not dismissed lightly as a power source for electric vehicles. It is, in fact, the only type of battery being used in large-scale prototype vehicle trials. Chloride Batteries UK are currently conducting several such trials. Further, nickel-cadmium batteries are used extensively in France for electric vehicle propulsion, example by Renault and Peugeot. The nickel-zinc system is another viable candidate for electric vehicle propulsion based on its high energy density and power density.