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

The low temperature behaviors of Li/TEGDNM/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 degrees C, but 357 mAh g(-1)-sulfur at low temperature of -10 degrees 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 degrees C, respectively. (c) 2006 Elsevier B.V. All rights reserved.