Influence of Phase Variation of ZnMn2O4/Carbon Electrodes on Cycling Performances for Li-ion Batteries

Due to the high specific capacity and low cost, transition metal oxides (TMOs) exhibit huge potential as anode materials for high-performance Li-ion batteries. This study presents the facile synthesis, structural study and electrochemical investigation of ZnMn2O4/carbon (ZMO/C) electrodes. Stabilization of the redox reaction and functional loading of conductive carbon are employed to improve their reversible Li+ storage performance. In the calcination process with carbon, analyzed via high-temperature X-ray diffraction, the tetragonal ZnMn2O4 undergoes a phase change into MnO/ZnO under an inert atmosphere at around 350 °C, while the initial ZnMn2O4 phase is transformed into Mn2.03O4/ZnO composite phases under air. The influences of the calcinating temperature and carbon loading on electrochemical performance are investigated, and the excellent cycling stability of ZMO/C electrodes is ascribed to the stable redox reaction and carbon loading. This strategy has led to particular improvement in the structural/electrochemical stability and long-term Li+ storage for conversion electrodes.