Recent technological advances in designing electrodes and electrolytes for efficient zinc ion hybrid supercapacitors

Abstract

Rechargeable zinc ion hybrid supercapacitors (ZIHSCs) have gained significant research and technological interest because they synergize the benefits of zinc ion batteries (ZIBs) with high energy density and supercapacitors (SCs) with high power density and cycling stability. They are considered as promising candidates for next-generation high-performance energy storage systems (ESSs) owing to their satisfactory energy-power combination, inherent safety features, low cost, and excellent electrochemical stability. The power of ZIHSCs lies in their suitably chosen electrode (cathode and anode) materials, optimized electrode architecture, and optimized electrolyte governing charge storage behavior. Although ZIHSCs have made some remarkable advancements in this regard, the current scenario is distant from what is necessary for their widespread practical application and hence, poses a major scientific as well as technological challenge to the research community. Therefore, further development in understanding of the intricate Zn ion storage mechanism in rationally designed novel electrode materials is highly coveted towards realizing novel, multi-functional ZIHSC devices with exceptional energy-power densities and ultra-long cycle life. This review is designed to cover the foundations and current scientific and technological achievements in the field of ZIHSCs, including their compositions, types, electrode materials, electrode design strategies, charge storage mechanisms, beneficial traits, electrolyte compositions, and newly created devices. Additionally, potential drawbacks with current generation ZIHSCs with possible solution strategies are also highlighted. The goal of this in-depth analysis is to provide a useful understanding of ZIHSCs that would be effective for their large-scale development and practical deployment as high-performance ESSs in a variety of applications.