Disorder has emerged as a critical yet underexplored design parameter in governing electrochemical functionality across electrode and electrolyte materials in lithium batteries. In high-Ni layered cathodes, oxygen instability is conventionally attributed to increasing Ni content; however, our findings reveal that oxygen loss originates not from Ni concentration itself but from local transition-metal (TM) disorder. Comparative studies of LiNixCoyMn1–x–yO2 compositions show that TM clustering destabilizes the anionic framework by creating energetically unfavorable 3Ni–O configurations, thereby facilitating oxygen vacancy formation and O₂ dimerization despite reduced bulk oxygen oxidation. Meanwhile, in garnet-type superionic conductors, disorder in the lattice vibrational spectrum plays a decisive role in enabling ultrafast Li-ion transport. Through Ta doping in Li₆.₆La₃Zr₁.₆₃Ta₀.₄O₁₂ (LLZTO4) relative to Li₆.₂₄La₃Zr₂Al₀.₂₄O₁₁.₉₈ (LLZO), we demonstrate that enhanced phonon anharmonicity dynamically diversifies the energy landscape, lowering migration barriers and promoting collective ion motion beyond the single-ion hopping limit. Together, these findings establish disorder — whether in cationic sublattices or vibrational dynamics — as a unifying principle that dictates structural stability and ion transport in oxide cathodes and solid electrolytes. This disorder-centered paradigm offers design strategies for next-generation high-energy-density and solid-state batteries.
Bio: Yong-Mook Kang completed his B.S. (1999), M.S. (2001), and Ph.D. (2004) at Korea Advanced Institute of Science and Technology. He worked as a senior researcher at Samsung SDI Co., LTD. He is currently a professor in the Department of Materials Science and Engineering at Korea University, South Korea, as well as at KU‐KIST Graduate School of Converging Science and Technology, Korea University. His research interests cover electrode and catalyst materials for rechargeable batteries. He was appointed as RSC (Royal Society of Chemistry) fellow and representative of Korea in 2015, a member of Y-KAST(Young Korean Academy of Science and Technology) in 2020, and an academician of APAM(Asia Pacific Academy of Materials) in 2024.