Properties of solid electrolyte interphase formed by prop-1-ene-1,3-sultone on graphite anode of Li-ion batteries

Abstract

The physical and chemical properties of the solid electrolyte interphase (SEI) formed by prop-1-ene-1,3-sultone (PES) on graphite anode in propylene carbonate (PC) based electrolyte for lithium ion battery were investigated by charge–discharge test, scanning electron spectroscopy with energy dispersive X-ray spectroscopy (SEM–EDS), Fourier transform infrared spectroscopy (FTIR), and X-ray photoelectron spectroscopy (XPS). It is found that the charge–discharge performance of the cell LiCoO2/natural graphite (NG) using PC-based electrolyte containing 3wt% PES is superior to that containing 6wt% propane sultone (PS), an SEI formation additive that has the similar molecular structure to PES but is reduced not as easily as PES. The results from SEM–EDS, FTIR and XPS show that the structure of graphite has been protected and some S-containing species are proven to be components of the SEI, suggesting that the preferable reduction of PES plays an important role in the formation of a protective SEI on NG.