Presentation Title: Niobium-Modified Cathode Materials of High-Voltage Spinel Lithium Nickel Manganese Oxide for Li-ion Batteries

Abstract：

High-voltage spinel lithium nickel manganese oxide (LiNi_0.5Mn_1.5O₄, LNMO) exhibits an ultra-high working voltage (4.7 V vs. Li+/Li), high power density, excellent low-temperature performance, superior thermal stability, and low cost. The main technical challenges of LNMO is to solve the electrolytes decomposition under high voltage and the dissolution of Mn, especially during storage and cycling at the elevated temperature. By employing strategies such as lithium enrichment, doping, coating, controlling oxygen stoichiometry, optimizing particle size, and developing high-voltage electrolytes, the structural and interface stability of the material/electrolyte can be enhanced, thereby reducing Mn dissolution and improving overall material stability. Introducing Nb can transform polyhedral single crystals into spherical single crystals, a mechanism is similar to that of spherical LMO, primarily driven by the adsorption and catalytic effects of Nb on the LNMO surface. Nb-modified LNMO demonstrates improved cycling stability. Once these technical bottlenecks are resolved, LNMO will have great potential in the industrial application for the power battery and energy storage markets.

Bio：

Dr. Yongyao Xia is a professor in the Department of Chemistry in Fudan University. He received a PhD degree in Energy-Related-Material Science in Saga University, Japan in 1997. His research interests involve advanced materials and technologies for energy storage and conversion devices, e.g., lithium(sodium)-ion batteries, electrochemical supercapacitors and new battery systems etc. He has published more than 500 papers in peer-reviewed scientific journals,0 H-index is 111. He is the High Cited Researcher in 2017-2024 by Clarivate Analytics. He becomes a fellow of the International Society of Electrochemistry (ISE) in 2019. He received the Battery Division Technology Award of the Electrochemical Society (ECS) in 2018, and the Technology Award of the International Battery Materials Association (IBA) in 2019. He served as the Editor ofJournal of Power Sources,the President of theChinese Society of Electrochemistry (CSE)(2015-2022).