Plastic and Flexible Micro-Electrochemical Supercapacitor Based on Cluster-Assembled Carbon

Abstract

Flexible, thin micro-electrochemical supercapacitors (MES) are attracting much attention in electronics for their capability of delivering short power pulses with high stability over repeated charge/discharge cycling. Supersonic Cluster Beam Deposition (SCBD) is an effective strategy for the development of nanostructured, binder-free porous carbon electrodes. It consists in the deposition of low kinetic energy clusters producing films with very low-density and high porosity. The use of SCBD for carbon cluster deposition allows to obtain very high deposition rates and highly collimated beam (divergence <20 mrad) which are suitable for the room temperature deposition of patterned nanostructured films by using stencil masks on a wide variety of substrates including polymers. We exploited SCBD, for the development of a planar, high voltage MES featuring nanostructured carbon electrodes deposited on a flexible plastic Mylar substrate and ionic liquid-based electrolyte. Here, the electrochemical performance at different temperatures of the MES which operate above 2.5 V with a capacitance density approaching approaching 10 F cm-3,and delivering 9 mWh cm-3 and 2.5 W cm-3 above room temperature is reported. ACKNOWLEDGMENTS RFO, Ricerca Fondamentale Orientata, is acknowledged for financial support.