Anchoring Nickel and Stabilizing Oxygen in Coherent LiNiO <sub>2</sub> @LiFePO <sub>4</sub> Composite Cathode Materials for Rechargeable Lithium‐Ion Batteries
Zhichen Hou, Wanying Wang, Wanying Wang, Meng Yao, Kuiming Liu, Fanqi Kong, Xinhui Huang, Yue Li, Guoyu Ding, Meng Yu, Weichao Wang, Weichao Wang, Fangyi Cheng
Abstract
Abstract LiNiO 2 is an appealing cathode material for Li‐ion batteries because of high energy density and low cost but suffers from irreversible phase transition and surface instability. Herein, a ball‐milled LiNiO 2 @LiFePO 4 composite with oriented coherent combination is reported with enhanced structural stability and Li + diffusion. The coherent oriented channels are demonstrated to favor the reversible and rapid Li + intercalation during the H2‐H3 phase transition, which significantly alleviates structural strain accumulation. The covalent P─O bonds anchored on the LiNiO 2 surface stabilizes the Ni sites, mitigating surface reconstruction and lattice oxygen loss. The LiNiO 2 @LiFePO 4 cathode exhibits a specific capacity of 210 mAh g −1 and an initial Coulombic efficiency of 93.7% at 0.1 C, along with a remarkable rate capability of 156 mAh g −1 at 10 C. Furthermore, the full cells pairing LiNiO 2 @LiFePO 4 cathode and graphite anode deliver a considerable energy density over 280 Wh kg −1 and a remarkable capacity retention. This study offers an effective approach of phosphate coalesce to upgrade high‐capacity nickel‐rich oxide cathode materials.