Active Crystal Facets Stabilization Strategy Achieves High‐rate Layered Metal Oxide Cathode Materials

Abstract Layered oxides store and release energy through the insertion and extraction of Li‐ions, and the diffusion rate of Li‐ions within these oxides directly affects the charging and discharging rates of Li‐ion batteries. Unlike previous approaches that focus on improving battery rate performance by reducing the size of active particles, this study synthesizes layered metal oxides with Mg embedded in the () active crystal facts (ACFTs), which feature an unsaturated coordination structure. This unique structure facilitates the reversible insertion of large quantities of Li‐ions at high rates. The rapid Li‐ion transfer, buffered volume expansion, and stable ACFT enable Li 0.977 Mg 0.01 CoO 2 to deliver a specific capacity of 210 mAh g −1 in the 3–4.6V range at 1C, with 81% capacity retention after 300 cycles and Li 1.2 Ni 0.13 Co 0.13 Mn 0.54 O 2 shows a voltage decay of only 0.15 mV per cycle. This study unveils the stabilization mechanisms of ACFTs and proposes a universal strategy for synthesizing high‐rate cathode materials.