Research On A Long Cycle Life,High Coulombic Efficiency Iron Molten Air Battery

Iron molten air cell is a new battery class with the advantage of superior theoretical energy density,lowcost,and environmental friendliness.It will be widely applied in the electric grid for energy storage.However,the research of iron molten air battery is still in the preliminary stage of exploration.Despite the recent advancements in iron molten air batteries,great chalenges still remain to realize cycling stability,high energy efficiency and long-term cycling life.In this thesis,a new iron molten air battery will be demonstrated in a electrolyte and air electrode perspective for large-scale energy storage.Two bifunctional air electrodes are prepared to improve its performance.The KCl-LiCl in the KCl-LiCl-LiOH eutectic electrolyte used in our previous study is replaced with Li0.87Na0.63K0.50CO3 eutectic electrolyte with added Na OH and Fe2O3.A fin air electrode configuration is designed to improve the coulombic efficiency.Cycling tests for the iron molten air battery showed stable performance through 450 cycles with near 100% coulombic efficiency and average discharge potential of ~1.08 V when charged at a constant current of 0.05 A and discharged over a constant 100 ? load to 0.7 V cutoff at 500 ?.Moreover,the iron molten air battery had an excellent high-rate response up to 6.4 C with a high coulombic efficiency of 95.1 %.These results provide critical advances in developing iron molten air batteries with high efficiency and long-term service life.An air electrode with higher-activity was demonstrated for the first time.It was found that the lithiated NiO nanoparticles uniquely decorated with lithiated PdO nanoislands are in situ formed during the battery cycling.The results showed that PdO nanoislands decorating lithiated NiO nanoparticles can enhance the iron molten air battery.The air electrode exhibited more efficient activity at catalyzing OER/ORR,an excelent low discharging polarization,and a superior rate performance compared with the bare Ni O catalyst.The iron molten air battery can cycle stably through 100 cycles with the highest coulombic efficiency of 98.7% and average discharge potential of ~1.10 V when charged at a constant current of 0.05 A and discharged over a constant 100 ? load to 0.7 V cutoff at 500 ?.The catalyst NiO nanosheets array was prepared to impove air electrode.The results show that Ni O nanosheets array can reduce the overpotential of charging and discharging,and improve the rate performance of the battery.Cycling tests for the iron molten air battery showed stable performance through 100 cycles with the highest coulombic efficiency of 99.6% and average discharge potential of ~1.12 V when charged at a constant current of 0.05 A and discharged over a constant 100 ? load to 0.7 V cutoff at 500 ?.