Influence of phase variation of ZnMn2O4/carbon electrodes on cycling performances of Li-ion batteries

Abstract

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 Mn_2.03O₄/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.