Tuning the phase evolution pathway of LiNi0.5Mn1.5O4 synthesis from binary intermediates to ternary intermediates with thermal regulating agent

• 作者: Libin Wu Hua Huo Qun Wang Xucai Yin Shu Guo Jiajun Wang Chunyu Du Pengjian Zuo Geping Yin Yunzhi Gao
• 来源期刊: 能源化学
• 年，卷（期）: 2022,（2）
• 页码范围: 62-70
• 页数: 9页
• 语种: 英文

摘要

Transition metal cation ordering is essential for controlling the electrochemical performance of cubic spinel LiNi0.5Mn1.5O4 (LNMO),which is conventionally adjusted by optimizing the high temperature sin-tering and annealing procedures.In this present work,multiple characterization techniques,including 6,7Li NMR,XRD and HRTEM,have been combined to trace the phase transformation and morphology evo-lution during synthesis.It has been illustrated that simultaneous formation of LiMn2O4 (LMO) and LiNiO2(LNO) binary oxides and their conversion into highly reactive LixNi3+yMn3.5+zO ternary intermediate is a thermal dynamically difficult but crucial step in the synthesis of LNMO ternary oxide.A new strategy of modifying the intermediates formation pathway from binary mode to ternary mode using thermal reg-ulating agent has been adopted.LNMO synthesized with thermal regulating agent exhibits supreme rate capability,long-cycling performance (even at elevated temperature) and excellent capacity efficiency.At a high rate of 100 C,the assembled battery delivers a discharge capacity of 99 mAh g-1.This study pro-vides a way to control the formation pathway of complex oxides using thermal regulating agent.