Non-free water dominated electrolyte architectures for zinc-based batteries: toward sustainable long-life zinc-based energy storage solutions

Abstract

Zinc (Zn)-based energy storage systems have garnered significant attention as promising candidates for grid-scale energy storage due to their inherent safety, environmental benignity, cost-effectiveness and so on. However, the persistent challenge of parasitic side reactions on the Zn metal anode in common aqueous electrolytes continues to impede practical implementation. This topical review highlights the latest research progress in paradigm-shifting electrolyte engineering strategies evolving from liquid to solid systems based on non-free water dominated electrolyte architectures, mainly including lean-water liquid electrolytes, gelatinized electrolytes, and solidified electrolytes. A comprehensive overview of the major electrochemical challenges of common pure aqueous electrolytes is firstly provided. Subsequently, the advancements in structural design strategies for electrolyte architectures with diverse water regulation are explored in depth, along with a detailed discussion of the corresponding electrochemical performance of cells including half and full cells. Finally, we examine the future challenges in developing practical electrolytes with optimized electrochemical properties. This review provides a fresh perspective on designing electrolytes for application in next-generation commercial Zn-based energy storage systems.