High stability graphite/electrolyte interface created by a novel electrolyte additive: A theoretical and experimental study

A novel electrolyte additive 3-sulfolene (3SF) for graphite anode is proposed in this work according to the DFT calculation. The calculated electron affinity energy of the investigated solvents and additives reveals that 3SF shows the highest reductive activity, which is further confirmed by the cyclic voltammetry test. The characterization results from charge/discharge cycle, scanning electron microscope, transmission electron microscope and elemental mapping demonstrate that the preferential reduction of 3 wt% 3SF additive generates a thin and uniform SEI film on the graphite surface, which effectively suppresses the continuous co-insertion and reduction of PC-based electrolyte, resulting in high cyclic stability of Li/graphite cell in PC-based electrolyte. Importantly, the ability of 3SF on improving the interfacial stability of graphite/PC-based electrolyte is better than that of the prop-1-ene-1,3-sultone which is believed to be the most promising candidates to alternate vinylene carbonate. (C) 2018 Elsevier Ltd. All rights reserved.