Professor Wang Pengfei from the School of Electrical Engineering and Associate Professor Gao Zhibin from the School of Materials Science and Engineering at Xi'an Jiaotong University collaborated to address the performance limitations of O3-type cathodes in sodium-ion batteries, which are constrained by slow Na+ diffusion kinetics accompanying complex phase transitions during electrochemical processes. They employed a methodology combining theoretical model design, first-principles calculations, and experimental measurements to enhance the configurational entropy of transition metal layers, shorten the spacing between them, and extend the octahedral-tetrahedral-octahedral pathways for Na+ transport. As a result, they developed a novel high-entropy cathode material for sodium-ion batteries. Their research findings were recently published in Advanced Materials.
The cathode material exhibits minimal voltage hysteresis and excellent rate performance at high current densities, while also demonstrating outstanding fast-charging and slow-discharging capabilities. Electrochemical testing combined with molecular dynamics simulations confirmed the lower migration energy barriers of this high-entropy material, thereby enhancing the Na+ diffusion coefficient. This work underscores the importance of high-entropy structural design for transition metals and provides crucial insights for developing high-energy-density, high-power O3-type layered oxide cathode materials.
Related Paper Information: https://doi.org/10.1002/adma.202312300
