Ru- and Cl-Codoped Li3V2(PO4)3 with Enhanced Performance for Lithium-Ion Batteries in a Wide Temperature Range

Li3V2(PO4)(3) (LVP) is a promising cathode material for lithium-ion batteries, especially when used in a wide temperature range, due to its high intrinsic ionic mobility and theoretical capacity. Herein, Ru- and Cl-codoped Li3V2(PO4)(3) (LVP-Ru-x-Cl-3(x)) coated with/without a nitrogen-doped carbon (NC) layer are synthesized. Among them, the optimized sample (LVP-Ru-0.05-Cl-0.15@NC) delivers remarkable performances at both room temperature and extreme temperatures (-40, 25, and 60 degrees C), indicating temperature adaptability. It achieves intriguing capacities (49 mAh g(-1) at -40 degrees C, 128 mAh g(-1) at 25 degrees C, and 123 mAh g(-1) at 60 degrees C, all at 0.5 C), long cycle life (94% capacity retention after 2000 cycles at 25 degrees C and 5 C), and high-rate capabilities (up to 20 C). The structural evolution features and capacity loss mechanisms of LVP-Ru-0.05-Cl-0.15@NC are further investigated using in situ X-ray diffraction (XRD) at different temperatures (-10, 25, and 60 degrees C) during redox reactions. Theoretical calculations elucidate that Ru- and Cl-codoping can greatly improve the intrinsic diffusion coefficient of LVP by reducing its bandgap energy and lowering the energy barrier of lithium-ion diffusion. In all-weather conditions, the dual-element co-doping strategy is critical for increasing electrochemical performance.

Automated summary

Li3V2(PO4)(3) (LVP) is a promising cathode material for lithium-ion batteries, and this study focuses on the synthesis and characterization of Ru- and Cl-codoped LVP coated with/without a nitrogen-doped carbon (NC) layer. The optimized sample (LVP-Ru-0.05-Cl-0.15@NC) exhibits remarkable performances at both room temperature and extreme temperatures (-40, 25, and 60 degrees C), with intriguing capacities, long cycle life, and high-rate capabilities. In situ X-ray diffraction (XRD) and theoretical calculations provide insights into the structural evolution and capacity loss mechanisms of the material.