Abstract: A battery augmentation system and method is disclosed. It is particularly designed for the augmentation of batteries in electric or hybrid vehicles. The system comprises of conversion means operatively connected between an auxiliary power system and a electric-motor-battery of the vehicle, wherein the conversion means converts an output signal from the auxiliary power system into a converted signal. The converted signal supplements the electric-motor-battery output voltage preventing it from dropping below a predefined level, thus preventing damage to the electric-motor-battery. The system makes further use of an external battery which can be charged either by mains power or through the auxiliary power system of the electric/hybrid vehicle allowing the vehicle to be converted to a plug-in capable hybrid/electric vehicle.