Discharge behavior of lithium/sulfur cell with TEGDME based electrolyte at low temperature

Abstract The low temperature behaviors of Li/TEGDME/S cell was examined using discharge curves, SEM and impedance spectra. The first discharge capacity of Li/S cell with tetra(ethylene glycol) dimethyl ether (TEGDME) electrolyte was 1303 mAh g −1 -sulfur at 20 °C, but 357 mAh g −1 -sulfur at low temperature of −10 °C. The low temperature discharge characteristic is improved by adding 1,3-dioxolane (DOXL) and methylacetate (MA) to TEGDME electrolyte. The optimum composition of mixed electrolyte is MA–DOXL–TEGDME (5:47.5:47:5, v/v). The Li/S cell using the optimum electrolyte has the first discharge capacity of 994 and 1342 mAh g −1 -S at −10 and 20 °C, respectively.