Li-rich Mn-based cathodes for high-energy-density lithium batteries

Li-rich Mn-based oxides (LRM) have become key candidate materials for breaking through the energy density bottleneck of lithium-ion batteries due to their ultra-high specific capacity compared with that of traditional commercial cathodes. However, their practical applications have long been plagued by issues such as voltage fade and capacity decay, rooted in the intrinsic structural differences between Li 2 MnO 3 and LiNi x Co y Mn 1−x−y O 2 phases. This review systematically compares the structural and performance characteristics of mainstream inorganic cathodes, focusing on the electrochemical behavior and anion redox mechanism of LRM. It analyzes in depth the failure paths driven by two phase differences arising from mechanics, thermotics, electricity, and magnetism. Subsequently, multi-level structural modification strategies at the atomic, mesoscopic, and particle scale are summarized. Finally, the application and existing problems of LRM in solid-state batteries are discussed. This review aims to provide a systematic reference for the design optimization of LRM and their application in high-energy-density lithium batteries.