High-voltage non-aqueous Zn/K1.6Mn1.2Fe(CN)6 batteries with zero capacity loss in extremely long working duration

Zinc-ion batteries (ZIBs) have attracted intensive attention in large grid energy storage owing to the low cost and high safety, but are impeded by the lack of suitable cathode materials with both long-cycle and working time. To overcome the barrier, we construct a rechargeable non-aqueous zinc-ion battery comprising a new MnHCF cathode, non-aqueous Zn2+-containing electrolyte, and zinc anode. The in-situ XRD analyses reveal a reversible cubic-monoclinic phase transformation mechanism during cycling. The Mn3+/Mn2+ redox couple within a stable crystal framework ensures a high operation voltage of 1.6 V and a specific capacity of 65.5 mA h g(-1). Up to 94% capacity retention is maintained after 8500 cycles at 200 mA g(-1), beyond most reported non-aqueous ZIBs. Remarkably, the Zn/MnHCF batteries show nearly zero capacity loss in an extremely long working duration (over 6180 h) even after a break of one month, suggesting the excellent storage stability and potential applications.