A system of harvesting electrical power for use within a battery operated device includes a battery and a motor driven by the battery to impart rotational energy to a first shaft. The first shaft drives a multi-phase generator and produces output voltage signals with respectively untimed phase responses. A rectification circuit combines the voltage signals into a combined DC voltage output, and an inverter connected to the rectification circuit converts the DC voltage output to an AC voltage output. A battery charger connected to the inverter receives the AC voltage output for charging the battery. The harvested power includes power from voltage sources with unregulated, or untimed, phase responses.