Glycine-Nitrate Process for Synthesis of Na3V2(PO4)3 Cathode Material and Optimization of Glucose-Derived Hard Carbon Anode Material for Characterization in Full Cells

Cost-effective methods need to be developed to lower the price of Na-ion battery (NIB) materials. This paper reports a proof-of-concept study of using a novel approach to the glycine-nitrate process (GNP) to synthesize sodium vanadium phosphate (Na 3V 2(PO 4) 3 or NVP) materials with both high-energy (102 mAh g ？1 at C/20) and high-power characteristics (60 mAh g ？1 at 20 C). Glucose-derived hard carbons (GDHCs) were optimized to reduce both sloping and irreversible capacity. The best results were achieved for electrodes with active material heat treated at 1400 °C and reduced Super P additive. Sloping region capacity 90 mAh g ？1, irreversible capacity 47 mAh g ？1, discharge capacity 272 mAh g ？1 (of which plateau 155 mAh g ？1) and 1st cycle coulombic efficiency (CE) 85% were demonstrated. GDHC||NVP full cell achieved 80 mAh g ？1 (reversible) by NVP mass out of which 60 mAh g ？1 was the plateau (3.4 V) region capacity. Full cell specific energy and energy density reached 189 Wh kg ？1 and 104 Wh dm ？3, respectively. After 80 cycles, including rate testing from C/20 to 10 C, the cell cycled at 65 mAh g ？1 with 99.7% CE. With further optimization, this method can have very high industrial potential. View Full-Tex