The need for salable features, lower exhaust emissions, greater efficiency and improved safety for tomorrow's vehicles is increasing the demand for electrical power. Raising vehicle system voltage from twelve volts is seen as an effective step toward meeting future power requirements while increasing generation, rectification, transmission and switching efficiencies. Higher system voltage will require higher voltage energy storage devices, i.e. batteries. Implications for the design and function of vehicle batteries, as well as manufacturing and reliability, are substantial.