An innovative electronically-conducting matrix of the cathode for sodium sulfur battery

•Carbon felt good wettable with sodium polysulfides is prepared using hybrid sol.•Coated carbon felt shows little sulfur on the electrolyte at 100 mA cm−2 on charge.•Coulombic efficiency of the cell with the coated carbon felt retains above 99.9%.

An innovative electronically-conducting cathode matrix, that makes sodium sulfur (NaS) battery excellent in discharge-charge performance, is prepared by surface modification of a carbon felt with inorganic nanoparticles. A carbon felt is dipped into an inorganic-organic hybrid sol, dried, and heat-treated at 600 °C for 2 h in a flowing argon. Coated surface of the felt has been examined by scanning electron microscopy (SEM) equipped with energy dispersive X-ray spectroscopy (EDX) and scanning transmission electron microscopy (STEM). The cell prepared with the coated carbon felt shows 92% of charge acceptance and 99.9% of coulombic efficiency at 100 mA cm−2 of current density.