Recent Advances and Design Strategies on Positive electrode Materials for Aqueous Rechargeable Magnesium Batteries

Abstract

Lithium–ion batteries (LIBs) have been extensively used in energy storage in recent years. Nonetheless, their drawbacks, specifically in terms of safety, cost, and environmental impact, have resulted in an increasing demand for alternative rechargeable technologies. Aqueous rechargeable magnesium batteries (ARMBs) have emerged as promising candidates among these. They employ electrolytes dissolved in water and exhibit better stability and favorable electrochemical performance, helping to counter many of the problems associated with LIBs. In addition, the economic appeal of magnesium, its excellent electrochemical behavior, inherent safety, and ease of preparation have all led to an increase in research interest in ARMBs. This review outlines the structural properties and performance limits of various types of positive electrode materials, such as manganese-based and vanadium-based compounds, Prussian blue analogs, polyanionic compounds, layered double hydroxides, and emerging organic materials. It also summarizes some important design strategies, including structural and compositional engineering, interface and electrolyte synergy, composite and conductive network design, and AI-assisted screening approaches for future direction of positive electrode materials. These strategies are expected to effectively address the key challenges of ARMBs and promote their scalable development toward practical applications.