Presentation Title: Scalable Preparation and High-Temperature Cycling Stability of Niobium-Doped LiMn₀.₆Fe₀.₄PO₄/Carbon Composite Cathode Materials

Abstract: 

    The rapid development of electric vehicles and electrochemical energy-storage systems has created growing demand for high-performance lithium-ion batteries. LiMn₀.₆Fe₀.₄PO₄ (LMFP) is regarded as a promising cathode material because of its high operating voltage and energy density. However, its structural stability and cycling performance are compromised by Jahn–Teller distortion and transition-metal dissolution, with these problems becoming particularly severe at elevated temperatures. In this work, high-valence Nb⁵⁺ ions were introduced into the Li sublattice of LMFP through an industrially scalable coprecipitation–spray-drying process, enabling controlled Nb doping levels from 0 to 3%. Nb doping decreases antisite defects, accelerates Li⁺ diffusion, and effectively suppresses Jahn–Teller distortion and Mn dissolution. The optimized sample with 2% Nb doping delivers a discharge specific capacity of 148.4 mAh g⁻¹ after 150 cycles at 60 °C, corresponding to a high capacity retention of 95.07%. The simultaneous improvement in lattice stability and Li⁺ transport accounts for the enhanced electrochemical durability under harsh thermal conditions. These results demonstrate that Nb doping substantially improves the high-temperature cycling stability of LMFP by regulating its lattice structure and mitigating thermally accelerated degradation. This study provides a practical strategy for the scalable production of highly stable and long-lasting LMFP cathode materials and offers valuable guidance for the development of durable lithium-ion batteries capable of operating under demanding thermal conditions.

Biography: 

     Jisheng Zhou is a professor and doctoral supervisor at Beijing University of Chemical Technology. He received his bachelor’s degree from China University of Petroleum (East China) in 2005 and his Ph.D. degree from Beijing University of Chemical Technology in 2011. He joined Beijing University of Chemical Technology in the same year, where he successively served as a lecturer and associate professor before being promoted to professor in 2018. He has undertaken academic visits to the Institute of Inorganic Chemistry of the Russian Academy of Sciences, the Singapore University of Technology and Design, and the Nagoya Institute of Technology.

    His research focuses on electrochemical energy-storage materials, covering cathode and anode materials for lithium-ion and sodium-ion batteries, including lithium manganese iron phosphate cathodes, carbon anodes, and lithium/sodium metal anodes. His work emphasizes electrode microstructure design, interfacial chemistry regulation, and fundamental energy-storage mechanisms. He has led more than 20 research projects funded by the National Natural Science Foundation of China, the Outstanding Young Scientists Fund of the Xinjiang Production and Construction Corps, the Beijing Natural Science Foundation, and industrial partners.

    He has published more than 70 papers as a first or corresponding author in leading journals, including Nature Communications, Advanced Materials, Angewandte Chemie International Edition, ACS Nano, Advanced Energy Materials, and Advanced Functional Materials. His publications have received more than 6,000 citations, and five have been recognized as ESI Highly Cited Papers. He has filed more than ten Chinese invention patents, five of which have been granted. He serves on the editorial boards of the Journal of Inorganic Materials, Carbon Techniques, and the Journal of China University of Petroleum. His honors include the Beijing Science and Technology Award, the Beijing Outstanding Doctoral Dissertation Award, and a nomination for the National Excellent Doctoral Dissertation.