Advancements in cathode materials for lithium-ion batteries: Mechanism innovations, multiscale characterization, and data-driven design

As the global energy landscape transitions toward cleaner and more sustainable sources, the demand for efficient energy storage systems has become increasingly pressing. Lithium-ion batteries (LIBs) are among the most commercially successful electrochemical energy storage technologies due to their high energy density, long cycle life, and relatively low environmental impact, and are widely deployed in consumer electronics, electric vehicles, and grid-scale energy storage systems. As a core component of LIBs, cathode materials largely determine the energy density, cycling stability, and safety of the battery. This review systematically examines the developmental history and recent research progress of five representative LIB cathode materials, including lithium cobalt oxide, lithium manganese oxide, lithium iron phosphate, high-nickel ternary materials, and lithium-rich manganese-based materials, addressing the incomplete and outdated perspectives in existing literature. The crystal structures, key scientific challenges, and recent modification strategies, such as surface coating, bulk doping, structural design, and interface engineering, are comprehensively discussed. By integrating multiscale approaches, including in situ characterization techniques and machine-learning-assisted analysis, this review connects historical developments with emerging research frontiers and provides guidance for the rational design of next-generation high-performance, safe, and cost-effective LIB cathode materials.