Entropy Stabilized Li‐Rich Layered Oxide Nanoparticles for Advanced High‐Voltage Cathodes

ABSTRACT The performance enhancement of emerging flexible batteries relies on the development of advanced small‐particle electrode materials. However, current cathode materials with reduced particle size mostly suffer from low operating voltage, especially aqueous based electrodes. In this study, by using laser‐induced carbothermal method, we successfully fabricated high‐entropy doped Li‐rich nanoparticles as layered oxide cathodes that exhibit outstanding high‐voltage performances. The direct bottom–up nanocrystal growth enables the formation of such exclusive Li‐rich nanoparticles with unprecedentedly small diameter of 83.08 nm. As confirmed by atomic‐resolution imaging, operando x‐ray diffraction and synchrotron techniques analysis, the cathode achieves high lattice stability at elevated cut‐off voltage through the combined effects of heteroatomic composition and reduced particle diameters. Molecular dynamics simulations using machine‐learning interatomic potentials further demonstrate suppressed oxygen loss and stabilized transition‐metal framework in the high‐entropy doped cathodes. Consequently, the cathode operates steadily at voltage window of 2.5–4.8 V with ultrahigh power density of 877.9 Wh kg −1 at 1 C. The assembled full cell and fiber battery provide significant practical feasibility during high‐voltage cycling. This work provides an efficient strategy for designing high‐voltage flexible batteries, offering critical insights for next‐generation energy storage research.