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

Abstract

Abstract Li 3 V 2 (PO 4 ) 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 Li 3 V 2 (PO 4 ) 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 °C), indicating temperature adaptability. It achieves intriguing capacities (49 mAh g −1 at −40 °C, 128 mAh g −1 at 25 °C, and 123 mAh g −1 at 60 °C, all at 0.5 C), long cycle life (94% capacity retention after 2000 cycles at 25 °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 °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.