Sequential Coordination Templating and Catalytic Carbon Coating via a Single Manganese Modifier for High‐Performance Hard Carbon Lithium Storage

ABSTRACT In hard carbon anodes, initial Coulombic efficiency (ICE) and reversible capacity are difficult to enhance simultaneously. This work employs manganese acetate as a single modifier coupled with methane CVD, driving two sequential mechanisms in one‐step pyrolysis: at the low‐temperature stage, Mn 2+ coordinates with oxygen‐containing functional groups at carbon edge sites to form C─O─MnO bonds, inducing ordered carbon‐layer rearrangement; at the high‐temperature stage, these coordination bonds dissociate, and in situ‐generated MnO nanoparticles (∼18 nm) catalyze CH 4 decomposition, depositing a dense carbon coating ∼7.5 nm in thickness. Compared with the pristine hard carbon (0Mn‐900), the optimized 0.1Mn‐CVD1h boosts the ICE from 58.97% to 81.31% and the reversible capacity from 288.31 to 369.52 mAh g −1 , with 96.35% retention after 300 cycles at 1 A g −1 . A 500 mAh pouch‐type full cell with an LiNi 0.6 Co 0.2 Mn 0.2 O 2 (NCM622) cathode retains 85.14% capacity at 30C, 74.62% at −30°C, and 74.36% after 10 000 cycles at 5C. This work demonstrates that the sequential dual utilization of a single modifier, from coordination template to catalytic center, offers a promising pathway toward reconciling the trade‐off between capacity and ICE in hard carbon anodes.