Effects of ethylene sulfite as a supplementary film-forming additive on the electrochemical performance of graphite anode in EC-based electrolyte

The effect of ethylene sulfite (ES) as a supplementary film-forming additive on the electrochemical performance of graphite anode in ethylene carbon (EC)-based electrolyte is studied in this research by constant current charge-discharge test, cyclic voltammetry (CV), electrochemical impedance spectroscopy (EIS), X-ray photoelectron spectroscopy (XPS), and scanning electron microscopy (SEM). Results show that ES addition can change the composition of solid electrolyte interface (SEI) coating on the surface of graphite anode by inhibiting the formation of inorganic compounds in a specific stage. XPS and SEM results confirm that SEI formed in the ES-added electrolyte contains less inorganic compounds. EIS measurements further reveal that ES addition can significantly reduce the resistance of the SEI layer and interface of graphite anode-electrolyte.