Highly stable and nanoporous Na3V2(PO4)3@C cathode material for sodium-ion batteries using thermal management

Sodium vanadium phosphate (Na 3 V 2 (PO 4 ) 3 -NVP) a NASICON-type material with exceptionally high ionic conductivity is acknowledged as a potential cathode for high-performance Na-ion batteries. Herein, we report a facile sol-gel process for the preparation of NVP@C. The NVP@C produced has rhombohedral NASICON crystal structure and exhibit 3D interlink microstructure with porous morphology and carbon network. The NVP@C prepared at 900 °C display an initial discharge capacity of 99 mAhg −1 at a current density of 1C and ultralong lifespan of 1400 cycles at 10C (73 mAhg −1 ) with 93 % capacity retention. This superior electrochemical performance is attributed to the synergistic effect of high crystallinity , porous structure & conducting carbon network. This provides a high contact area between electrode/electrolyte, better electronic conductivity , and high mechanical strength . Additionally, this will also responsible for easy diffusion of electrolyte and speedy transport of ions which ultimately helps to accelerate the electrochemical performance. It is noteworthy that the prepared NVP@C shows highly stable electrochemical performance at higher current density (10C) with 100 % columbic efficiency. More significantly, the full cell comprising NVP@C electrodes showed capacity retention of 80 % after 500 cycles at 2C rate. These prima fascia result shows the potential of the process which provides a new understanding to design other cathode material . • Nanostructured Na 3 V 2 (PO 4 ) 3 @C exhibited capacity i.e. of 99 mAhg −1 at 1C. • NVP demonstrated ultralong cycle life of 1400 cycles at 10C (73 mAhg −1 ) with 94 % capacity retention. • Full cell comprising optimized NVP@C electrodes demonstrated cyclability of 500 cycles at 2C rate.