Electrochemical Properties of Li<sub>4</sub>Ti<sub>5</sub>O<sub>12</sub> Coated LiMn<sub>0.6</sub>Fe<sub>0.4</sub>PO<sub>4</sub> Prepared by Rheological Phase Reaction Method
Haoyan Gu, Weida Li, Q. Li, Xinran Li, Hao Yang, Quanjun Fu, Guangchuan Liang
Abstract
In this study, we fabricated LiMn 0.6 Fe 0.4 PO 4 /C (LMFP/C) materials employing the spray drying method. Subsequently, the LMFP/C composites underwent surface modification with Li 4 Ti 5 O 12 (LTO) using the rheological phase reaction method. LTO demonstrates high electrochemical activity and possesses significantly greater lithium-ion conductivity compared to LMFP. The developed composite coating serves a dual purpose by safeguarding the LMFP material against electrolyte erosion and facilitating the swift transfer of lithium ions and electrons. The results from transmission electron microscopy and energy-dispersive X-ray spectroscopy validated the successful coating of LTO onto the LMFP/C surface after the surface modification treatment. A comparative analysis was conducted between the pristine LMFP/C powder and the LMFP-LTO composite that underwent surface modification. The results reveal that the 2 wt% LTO-coated LMFP/C composite has the best electrochemical performance, manifesting specific capacities of 156 and 132.6 mAh g −1 at 0.2 and 5 C rate, respectively. Furthermore, the material demonstrated excellent cycle retention, with 95.4% capacity retention after 100 cycles at 1 C. Hence, LTO coating can be considered an efficacious strategy for enhancing the electrochemical performance of LMFP.