Smart, stretchable and wearable supercapacitors: prospects and challenges

Abstract

Among the various energy storage systems, supercapacitors are considered to be the most promising alternative to batteries due to their high power density, long cycle life and fast charge–discharge process. Especially, flexible electrochemical supercapacitors with their unique advantages such as flexibility, shape-conformability, and light weight are attracting ever-increasing attention to meet the current requirements for portable and wearable electric devices in modern energy storage markets. In this perspective, we summarize the most recent progress in flexible all-solid supercapacitors from the point of view of flexible electrode materials. Various flexible electrode materials like carbon nanotubes, graphene, and pseudo capacitive materials are discussed and their performance is comprehensively analyzed. In addition, an overview of the latest progress in strategies to improve the energy and power density is discussed. Further research targets in multifunctional integrated systems and challenges in realizing idealized flexible energy storage systems are also proposed.