High-entropy oxide anodes for lithium-ion batteries: Multi-element synergy-driven structural engineering and electrochemical breakthroughs

High-entropy oxides (HEOs) have emerged as highly promising anode materials for lithium-ion batteries (LIBs), benefiting from the synergistic effects of multiple constituent elements, entropy-driven structural stability, and tunable electrochemical performance. This review summarizes recent advances in HEOs for LIB anode applications, elaborates on their fundamental structural characteristics, configurational entropy, and dominant crystal types, and comprehensively compares key synthesis techniques, including solid-state reaction, coprecipitation, hydrothermal method, and metal-organic framework (MOF)-templated synthesis. The lithium storage mechanisms dominated by conversion reactions are highlighted, and effective strategies for enhancing electrical conductivity and cycling stability—via oxygen vacancy engineering, elemental doping, and hierarchical heterostructure design—are systematically summarized. Notably, spinel HEOs exhibit superior rate capability and long-term cycling stability, attributed to their intrinsic three-dimensional lithium-ion diffusion pathways that facilitate rapid ion transport. Finally, current critical challenges in rational composition design, in-depth mechanism elucidation, and large-scale fabrication are identified, and the pivotal role of computation-aided design and advanced in situ characterization techniques in developing high-performance HEO anodes is discussed, providing valuable theoretical and technical insights for advancing next-generation LIBs with long cycling stability and high energy density.