Rechargeable Zn-MnO₂ Batteries: Progress, Challenges, Rational Design, and Perspectives

As a new type of secondary ion battery, aqueous zinc-ion battery has a broad application prospect in the field of large-scale energy storage due to its characteristics of low cost, high safety, environmental friendliness, and high-power density. In recent years, manganese dioxide (MnO2)-based materials have been extensively explored as cathodes for Zn-ion batteries. Based on the research experiences of our group in the field of aqueous zinc ion batteries and combining with the latest literature of system, we systematically summarize the research progress of Zn-MnO2 batteries. This article first reviews the current research progress and reaction mechanism of Zn-MnO2 batteries, and then respectively expounds the optimization of MnO2 cathode, Zn anodes, and diverse electrolytes and their effects on battery performance. Additionally, primary challenges related to different components and their respective strategies for mitigating them are discussed, with the ultimate objective of offering comprehensive guidance for the design and fabrication of high-performance Zn-MnO2 batteries. Finally, the future research and development direction of aqueous Zn-MnO2 batteries with high energy density, high safety and long life is envisioned.