Comunicazione

# Mechanical energy harvesting from electrostrictive polymeric nanocomposites.

##### Zanoletti M., Vitulo P., Morina R., Callegari D., Quartarone E., Viola R., Martusciello M., Comoretto D., Dulio S., Mustarelli P., Patrini M.
Giovedì 15/09   15:00 - 18:30   Aula D - Marianna Ciccone   II - Fisica della materia
Harvesting systems capable of transforming mechanical vibration into electrical energy have attracted considerable interest with particular focus on electroactive polymers. We are developing harvester systems compatible to a shoe sole structure and capable of recovering energy from human gait, then sustaining the energy consumption of a sensor platform to monitor biophysical parameters. In this contribution, a composite material consisting of a polyurethane matrix filled with a high-$k$ ceramic nanofiller $(CaCu_{3}Ti_{4}O_{12})$ is fabricated by doctor blade coating. Single strips, with sputtered electrodes, are electrically connected in parallel increasing electrical capacitance. The required bias voltage is provided by two alternative solutions, a rechargeable battery or a custom electret made by corona charging. When a $50 {V}$ bias was supplied by the battery, we obtained energy density output of about $5 \mu J/cm^{3}.$ Utilizing the electret, we measured an energy density output a factor 3 to 10 higher. The energy, initially stored in a supercapacitor, will then be managed in an optimized way to power sensing components integrated in the shoe sole.