Optimizing the Performance of a Graphitized Carbon Xerogel as Cathode for Sodium Dual-Ion Batteries

The objective of this study is to optimize the performance of a graphitized carbon xerogel doped with graphene oxide (GXGO) as cathode for sodium dual-ion batteries. Carbon xerogels are synthetic materials produced in large amounts, with well-controlled chemistry, porosity and structure, by a simple and fast microwave process that has been scaled-up. The intercalation of PF6- anions from various NaPF6 salt-based electrolytes in a GXGO-based cathode is investigated by considering the influence of the upper cut-off voltage (UCOV) and of the electrolyte on the electrochemical parameters. The best results were attained in an electrolyte with a 2.0 M NaPF6 concentration in EC : EMC carbonate solvent mixture with added FEC, at a UCOV of 5.0 V. GXGO cathode provides a discharge capacity of 47 mAh g(-1) after 2500 cycles with a coulombic efficiency of 97 %. Moreover, it shows great cycling stability and capacity retention of essentially 100 % after the initial cycles.

Automated summary

The objective of this study is to optimize the performance of a graphitized carbon xerogel doped with graphene oxide (GXGO) as cathode for sodium dual-ion batteries. The intercalation of PF6- anions from various NaPF6 salt-based electrolytes in a GXGO-based cathode is investigated by considering the influence of the upper cut-off voltage (UCOV) and of the electrolyte on the electrochemical parameters. The best results were attained in an electrolyte with a 2.0 M NaPF6 concentration in EC : EMC carbonate solvent mixture with added FEC, at a UCOV of 5.0 V. GXGO cathode provides a discharge capacity of 47 mAh g(-1) after 2500 cycles with a coulombic efficiency of 97 %. Moreover, it shows great cycling stability and capacity retention of essentially 100 % after the initial cycles.