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

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 Xray 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 3 wt% PES is superior to that containing 6 wt% 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. (c) 2013 Elsevier Ltd. All rights reserved.