Fabric- and film-structured supercapacitor

Supercapacitors had gained much interest due to their high power density, long cycle life, and fast charge and discharge speed. However, traditional supercapacitors were commonly produced with rigid structures and liquid electrolytes that cause many limits in flexible and non-traditional end uses. Although liquid electrolytes can be replaced by polymer-based gel electrolytes, time-dependent high stiffness, and capacitance loss were found to be the main drawbacks. Herein, an all-solid-state supercapacitor based on fabric/film composition was studied. Activated carbon granule (ACG) was used as an electrode material and polyvinyl alcohol (PVA) with phosphorous acid was selected as both polymer matrix and electrolyte. The as-prepared supercapacitor exhibited the typical double-layer electrostatic capacitive behavior, showing a good specific capacitance of 0.998 mF cm−2 at the scan rate of 10 mV s−1. When ZnO nanoparticles were added, the supercapacitor was further enhanced, showing a better specific capacitance of 1.321 mF cm−2 at the scan rate of 10 mV s−1. The supercapacitor was capable of bending at any angle without suffering its performance. This result indicated that the fabricated supercapacitor structure was flexible, lightweight, and capable of being integrated into textile products.