International Journal of Energy Research, Vol.45, No.3, 4534-4542, 2021
Na3V2(PO4)(3)/C composites as low-cost and high-performance cathode materials for sodium-ion batteries
The carbon layer acting as a conductive medium is beneficial to overcoming the comparatively inferior electronic conductivity of Na3V2(PO4)(3). Based on this, Na3V2(PO4)(3)/C composites with diverse ratios of citric acid are synthetized via rheological phase reaction way in this work. The consequences display that the Na3V2(PO4)(3)/C-1.5 composite brings a higher initial discharge capacity of 113.2 mAh g(-1) at a current rate of 1 C with coulombic efficiency above 99% during all cycles. The discharge capacity retains at 117.6 mAh g(-1) at the 100th cycle. Even at the high current densities of 5 C and 10 C, the composite also shows superior cycling performance with negligible capacity fading. Its discharge capacities decline from 97 to 92.6 mAh g(-1) at 5 C and from 85.3 to 83.7 mAh g(-1) at 10 C. These remarkable outcomes arise from its preferable morphology with suitable carbon coating because both excess and skimpy carbon seriously affect the microstructure and electrochemical properties of Na3V2(PO4)(3)/C composites.
Keywords:carbon coating;cathode materials;Na3V2(PO4)(3);C;rheological phase reaction;sodium‐;ion batteries