Coordination-tuned Na3V2(PO4)3 cathodes for low-temperature sodium-ion batteries

Abstract

In this work, we developed a synergistic Nb⁵⁺ doping and SiO₄⁴⁻ substitution strategy to precisely tune the local coordination environment in Na₃V₂(PO₄)₃ (NVP), achieving simultaneous structural optimization and enhanced low-temperature performance. The optimized cathode demonstrates exceptional cycling stability (96% capacity retention after 3000 cycles at 10 A g⁻¹ and −20 °C) and remarkable fast-charging capability (60% state of charge in 14.1 minutes at −20 °C).