New type of energy harvester with electric double layer electrets

We demonstrated a new type of vibrational energy harvester based on an electric double layer (EDL) electret. By mechanically modulating interfacial area between vibrating electrode and the EDL electret, the electrode is electrostatically charged and discharged at different phases and electric current is generated. Owing to extremely large capacitance of the EDL electret, vibrational energy harvesters have the unique capability to electrostatically leverage the high-density charge accumulation to the electrode and obtained current density become as high as 9 μA/cm 2 even with low frequency vibration as low as 1 Hz.