An electrical energy storage system includes a plurality of electrical energy storage modules with each module having an associated operating voltage and each module being capable of outputting electrical power at a variable current at the associated operating voltage. The system further includes a plurality of electrical power modulation circuits electrically connected to an associated one of the modules thereby allowing the associated module to be electrically isolated from the other modules. Each power modulation circuit includes an arrangement for receiving the operating voltage and current of the associated module, transforming the operating voltage and current, and outputting electrical power at a voltage that is independent of the module operating voltage of the associated electrical energy storage module. The system further includes an overall master controller electrically connected to each of the power modulation circuits of each module to control the electrical power output from each of the modules.