Flexible Asymmetric Supercapacitors

This chapter focuses on the guidelines on the material design and charge balance of a typical asymmetric flexible supercapacitor (AFSC) device. AFSCs device can be fabricated by constructing two flexible dissimilar electrodes (a Faradaic positive electrode and a capacitor-type negative electrode), a separator and, in most cases, quasi-solid-state electrolyte in a soft package. The chapter illustrates different types of various newly developed AFSCs, including sandwich-type, fiber-type, and the other type of AFSCs devices, based on various electrode materials. It discusses the future developing trends and challenges to provide certain reference to readers on how to contrive AFSCs device. The smart integration of AFSCs as power sources with energy harvesting units (solar cells, fuel cells, nanogenerators) or energy consuming units (sensors, LEDs, displays) would be a promising strategy for rational arrangement and utilization of energy, which is accordant with the future goals of sustainable development.