A Solidified Ionic Liquid for Vibrational Energy Harvesters

Abstract

We propose a high power-output vibrational energy harvester based on ionic liquid. Ionic liquid enables a very large capacitance (1.0-10 µF cm^-2) on the electrode at a bias voltage less than 1.9 V due to its extremely thin (∼ 1 nm) electrical double layer. By mechanical squeezing and dragging the ionic liquid droplet that was solidified with a polymer additive, between a pair of electrodes at 15 Hz, we stably obtained a current output of 22 µA cm^-2 at 1.5 V.