Recent Advances in Rechargeable Aqueous Magnesium-ion Batteries

Abstract

Aqueous rechargeable batteries have received widespread attentions due to their advantages like low-cost, intrinsic safety, environmental-friendliness, high ionic conductivity, ease operation, and simplified manufacturing in air. Magnesium (Mg), represented by its abundant resources, cost-effectiveness, stability, non-toxicity, high volume specific capacity, and low redox potential, has captured scientific interests as a potential option for rechargeable batteries. Initially, rechargeable magnesium-ion batteries predominantly utilized organic electrolytes, which had drawbacks such as high cost, strong corrosiveness, poor cycling performance, and low conductivity. Therefore, researchers are starting to shift their focus towards the cost-effective, safe, and environmentally friendly aqueous Mg-ion batteries (AMIBs). Nonetheless, there are significant challenges in AMIBs like low specific capacities and energy densities, which need to be overcome for practical applications. To inspire further research, this work provides a comprehensive overview of recent advancements in AMIBs, covering topics such as electrolytes, cathode materials, anode materials, and full cells. Through this work, we aim to show the great potential of AMIBs, especially the full battery based on Mg metal anodes. Recent breakthroughs in Mg-ion electrode materials and electrolytes have brought hope for the realization of high-performance mild AMIBs though they are still in their infancy.