Energy Harvesting from Vibration Using Polymer Electret

A vibration-driven electret generator has been developed for energy harvesting applications. Perfluorinated polymer electret with extremely-high surface charge density is employed for large power output. By using parylene as the spring material, a low-resonant-frequency MEMS generator is realized. Large in-plane amplitude of 0.8 mm at the resonant frequency as low as 37 Hz has been achieved. With our early prototype, output power of 0.28 μW has been obtained.