Research progress on high-entropy oxides as advanced anode, cathode, and solid-electrolyte materials for lithium-ion batteries

Amidst growing energy demands and the advancement of new energy technologies, there is an increasing need for rechargeable batteries with higher energy densities and longer cycle lives. Recently, single-phase solid-solution high-entropy oxides (HEOs), known for their multi-component complex composition, have gained significant attention in the field of lithium-ion batteries. The entropy-stabilising effect of these materials contributes to their high structural and cycling stability, making HEOs promising candidates as next-generation electrode materials for lithium-ion batteries. This review summarises current research on HEOs in their roles as anode, cathode, and solid-state electrolyte materials, including the synthetic methods and characterization techniques employed to develop these high-entropy oxides. Furthermore, this paper critically examines existing research challenges and potential mechanisms and anticipates the future application of high-entropy oxides in lithium-ion battery technologies.