Pinning the Surface Layered Oxide Structure in High Temperature Calcination Using Conformal Atomic Layer Deposition Coating for Fast Charging Cathode

Abstract In the solid‐state synthesis of layered oxides, achieving cathode powder with precise morphology, crystal structure, and surface properties demands a delicate balance between thermodynamics and kinetics. Elevated temperatures are indispensable for driving the reaction toward completion, facilitating the formation of ordered layered structures essential for efficient lithium‐ion transportation in Li‐ion batteries. However, high temperatures risk inducing Li/Ni mixing and rock‐salt formation, particularly pronounced in layered oxides rich in Ni content, detrimentally impacting their performance. To address this challenge, the approach involves a precisely designed conformal coating with a high affinity for oxygen atoms, strategically employed to pin the surface layered oxide structure even under elevated temperatures. By preventing undesired surface decomposition during the high‐temperature lithiation process, this innovation fosters the formation of well‐ordered layered structures on the surface. Consequently, this pioneering strategy substantially mitigated phase separation during high‐rate cycling, thereby unlocking exceptional rate capability and cycle stability in layered oxide cathodes. The strategy establishes a new pathway for synthesizing next‐generation, high‐power density battery materials.