Large Scale One-Pot Synthesis of Monodispersed Na3(VOPO4)2F Cathode for Na-Ion Batteries

Abstract

Na-ion batteries (NIBs) have received significant interest as potential candidates for large-scale energy storage owing to the widespread distribution of sodium and superior low-temperature performance. However, their commercial application is usually hindered by the high production cost and inadequate performance for electrode materials, particularly for cathodes. Na3(VOPO4)2F (NVOPF) has been recognized as one of the most promising cathodes for high-energy NIBs owing to the high working voltage and energy density. Here, we report a facile highly efficient room-temperature solution protocol for large-scale synthesis of NVOPF cathode for NIBs. By simply regulating pH, NVOPF can be obtained, which delivered a discharge capacity of 120.2 mAh g-1 at 0.1 C and 72% capacity retention over 8000 cycles at 25 C. Besides, the kilogram-level NVOPF products have been synthesized, and 26650 cylindrical cells were fabricated, which exhibit excellent cycling stabilities, remarkable low-temperature performance with comparable safety features. We hope our findings could provide insights on the industrial application of NVOPF in NIBs.