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

Abstract

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 (Na3V2(PO4)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.

Optimizing ultramicroporous hard carbon spheres in carbonate ester‐based electrolytes for enhanced sodium storage in half‐/full‐cell sodium‐ion batteries

“…Compared to previously reported HC as an electrode in half‐cells under different ether‐based electrolyte systems, 36,40,42,43,45,46,56,59–76 HCMS‐PC shows much higher reversible capacity at current densities of 30 and 300 mA g −1, as shown in Figure 6A. In addition, the reported 36,57,58,77–84 full‐cell (NVP//HCMS) data (Figure 6B) indicate that other ester‐based electrolytes show comparable reversible capacity and rate capability.…”

“…Compared to previously reported HC as an electrode in half-cells under different ether-based electrolyte systems, 36,40,42,43,45,46,56,[59][60][61][62][63][64][65][66][67][68][69][70][71][72][73][74][75][76] HCMS-PC shows much higher reversible capacity at current densities of 30 and 300 mA g −1, as shown in Figure 6A. In addition, the reported 36,57,58,[77][78][79][80][81][82][83][84] full-cell (NVP//HCMS) data (Figure 6B) indicate that other ester-based electrolytes show comparable reversible capacity and rate capability. The present work reports the optimization of the esterbased binary electrolytes using HCMS as the electrode material to achieve better 3-RCs property.…”

Hierarchically porous closed-pore hard carbon as a plateau-dominated high-performance anode for sodium-ion batteries

“…4(c). Interestingly, due to the higher working voltage of 3.22 V and higher Na-content in the fully sodiated state, the energy density reached 292 W h kg −1 , which is higher than the reported layered oxide//HC, 42–45 and polyanionic//HC 46,47 based SIBs and very competitive with the LFP-type LIBs. 48,49 This work demonstrates high energy density SIBs using advanced hard carbon with integrated features to develop next-generation storage devices.…”

A Comparative Study of the Structural and Electrochemical Properties of Na3V2(PO4)3/C Cathode Materials for Na‐ion Batteries Prepared by Sol‐Gel vs. Solid‐State Methods

“…This clearly gives the electrode obtained from a solgel method a higher capacity than the candidate electrode at 10 C. The rate capability and cycling stability of the prepared cathodes are consistent with Na 3 V 2 (PO 4 ) 3 cathodes studied by previous works. [46][47][48] Moreover, electrochemical impedance spectroscopy (EIS) was used to study the electronic conductivity of the synthesized cathodes after 300 cycles. These results are shown in Figure S8.…”