Solidified ionic liquid for high power-output vibrational energy harvesters

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