Research advances of amorphous metal oxides with the feature of Pseudocapacitance behavior in Lithium ion battery.

Amorphous metal oxides have emerged as a promising class of materials for advanced energy storage applications, owing to their unique structural characteristics including abundant defects/vacancies, highly permeable diffusion networks, and isotropic stress distribution. However, many studies have provided detailed descriptions and explanations of crystalline metal oxides, there is a lack of corresponding reviews on amorphous metal oxide materials, especially in terms of their applications in lithium-ion electrochemical energy storage and conversion. This comprehensive review systematically summarizes recent advancements in pseudocapacitive amorphous metal oxide anodes for high-performance lithium-ion batteries. We particularly highlight key mechanisms contributing to exceptional electrochemical performance from both theoretical and experimental perspectives: (1) excess pseudocapacitive lithium storage through more defect sites, (2) the evolution from conventional intercalation to surface-dominated pseudocapacitive charge storage, (3) enhanced interfacial lithium storage capacity, and (4) beneficial microstrain effects that improving structural stability and enhancing Li diffusion. Furthermore, we critically discuss the remaining challenges for practical implementation of these materials, while providing insightful perspectives on future research directions. This review aims to establish fundamental design principles for developing cost-effective, durable, and high-performance alkali metal batteries, offering valuable guidance for next-generation energy storage systems.