Recent Progress in Flexible Electrochemical Capacitors: Electrode Materials, Device Configuration, and Functions

Abstract

With increasing demand for portable, flexible, and even wearable electronic devices, flexible energy storage systems have received increasing attention as a key component in this emerging field. Among the options, supercapacitors, commonly referred to as ultracapacitors or electrochemical capacitors, are widely recognized as a potential energy storage system due to their high power, fast charge/discharge rate, long cycling life-time, and low cost. To date, considerable effort has been dedicated to developing high-performance flexible supercapacitors based on various electrode materials; including carbon nanomaterials (e.g., carbon nanotubes, graphene, porous carbon materials, carbon paper, and textile), conducting polymers (e.g., polyaniline, polypyrrole, polythiophene), and hybrid materials. A brief introduction to the field is provided and the state-of-the-art is reviewed with special emphasis on electrode materials and device configurations. Flexible electrochemical capacitors have been considered as one of the most promising candidates for lightweight, flexible, and wearable electronic devices in our society. The growing field of flexible electrochemical capacitors is reviewed with a focus on electrode materials and device configurations. In addition, the most promising advances and future challenges are identified. © 2015 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.