Temperature‐Dependent Electrochemical Properties and Electrode Kinetics of Na3V2(PO4)2O2F Cathode for Sodium‐Ion Batteries with High Energy Density

Abstract Phosphate cathode materials are practical for use in sodium‐ion batteries (SIBs) owing to their high stability and long‐term cycle life. In this work, the temperature‐dependent properties of the phosphate cathode Na 3 V 2 (PO 4 ) 2 O 2 F (NVPOF) are studied in a wide temperature range from −25 to 55 °C. Upon cycling at general temperature (above 0 °C), the NVPOF cathode retains an excellent charge/discharge performance, and the rate capability is noteworthy, indicating that NVPOF is a competitive candidate as a temperature‐adaptive cathode for SIBs. Upon decreasing the temperature below 0 °C, the cell performance deteriorates, which may be caused by the electrolyte and Na electrode, based on the study of ionic conductivity and electrode kinetics. This work proposes a new breakthrough point for the development of SIBs with high performance over a wide temperature range for advanced power systems.