Enhanced all-solid-state iron–air batteries via low-level K+ doping in iron oxide

Abstract

This study investigates the performance of all-solid-state iron–air batteries (ASSIABs) enhanced by low-level K⁺ doping in Fe₂O₃. K-doping significantly improves charge diffusion, optimizes the iron oxide reduction kinetics, and reduces structural perturbations associated with repeated phase transitions during cycling. These enhancements result in a coulombic efficiency of 100%, energy efficiency of 60%, and stable cycling over 100 cycles when operating at 800 °C. The battery demonstrates enhanced electrochemical kinetics and minimal degradation in performance, highlighting the potential of ASSIABs for scalable and efficient energy storage applications.