Design strategies for rechargeable aqueous metal-ion batteries

Rechargeable aqueous metal-ion batteries (AMBs) have attracted extensive scientific and commercial interest due to their potential for cost-effective, highly safe, and scalable stationary energy storage. However, their limited output voltage, inadequate energy density, and poor reversibility of ambiguous electrode reactions in aqueous electrolytes strongly limit their practical viability. This review aims to elucidate the challenges of existing AMBs from the material design to whole device applications. We summarize the emerging electrochemistry, fundamental properties, and key issues in interfacial behaviors of various classes of prevailing AMBs, including aqueous alkali metal-ion batteries and multivalent-ion batteries, and present an appraisal of recent advances for addressing the performance deficiency. Specifically, the progress of zinc-ion batteries is highlighted to provide a ubiquitous guideline for their commercialization in the grid-scale energy storage. Finally, we figure out the dominating general challenges for achieving high-performance AMBs, laying out a perspective for future breakthroughs.