Kinetic properties of sodium-ion transfer at the interface between graphitic materials and organic electrolyte solutions

Abstract Graphitic materials cannot be applied for the negative electrode of sodium-ion battery because reversible capacities graphite are anomalously small. To promote electrochemical intercalation into graphitic materials, interfacial transfer reaction at interface between graphitized carbon nanosphere (GCNS) and organic electrolyte solutions was investigated. The lithium-ion also evaluated comparison to transfer. From cyclic voltammograms, both can reversibly intercalate into/from GCNS in all electrolytes used here. In Nyquist plots, semi-circles high frequency region derived from Solid Electrolyte Interphase (SEI) resistance middle owing charge-transfer appeared. activation energies resistances were measured. values suggested that influenced by interaction solvents, anions or SEI. larger than expected based on week Lewis acidity sodium-ion. addition, dilute FEC-based smaller those concentrated electrolytes. lithium/sodium-ion CNS-1100 almost same as CNS-2900, indicating mechanism seemed highly low-graphitized each other. Graphic abstract