Abstract: This invention relates to power supply system having recharging unit with load isolation and its method of operation. The power supply unit has one or more energy storage device and such energy storage device is of low voltage rating when compared with the operating voltage of the load. The power supply units when operated through an intermediate section and an output combiner, due to alternative parallel and series connections of capacitors supplies to the load an enhanced voltage as required by the load with complete isolation between the recharging unit of the system and load. The recharging unit supplies the recharging voltage to the input battery whenever the input battery is isolated from the load. Due to which, the energy storage devices serves for large distance range and better speed range in case of electric vehicles.