Asymmetric Supercapacitor Electrodes and Devices. Issue 21 (28th February 2017) - Choudhary, Nitin
Abstract : The world is recently witnessing an explosive development of novel electronic and optoelectronic devices that demand more‐reliable power sources that combine higher energy density and longer‐term durability. Supercapacitors have become one of the most promising energy‐storage systems, as they present multifold advantages of high power density, fast charging–discharging, and long cyclic stability. However, the intrinsically low energy density inherent to traditional supercapacitors severely limits their widespread applications, triggering researchers to explore new types of supercapacitors with improved performance. Asymmetric supercapacitors (ASCs) assembled using two dissimilar electrode materials offer a distinct advantage of wide operational voltage window, and thereby significantly enhance the energy density. Recent progress made in the field of ASCs is critically reviewed, with the main focus on an extensive survey of the materials developed for ASC electrodes, as well as covering the progress made in the fabrication of ASC devices over the last few decades. Current challenges and a future outlook of the field of ASCs are also discussed. Abstract : Recent developments in asymmetric supercapacitor (ASC) electrode materials (anode and cathode) including carbonaceous materials, metal oxides/nitrides, conductive polymers, and 2D materials are highlighted. A rational electrode‐material design with tailored nanostructures endows significant improvement in the specific capacitance and energy density of ASCs. The resulting ASCs have the potential to function as a fast‐charging energy source for next‐generation flexible electronics, e‐textiles, and transportation applications.