Low Temperature Conductivity Study of Multi- Organic Solvent Electrolyte for Lithium-Sulfur Rechargeable Battery Application: Recent Study

The conductivity of an electrolyte plays a significant role in deciding the performance of any battery
over a wide temperature range from –40°C to 60°C. In this work, the conductivity of lithium bis
(trifluoromethanesulfonyl) imide (LiTFSI) at a varied salt concentration range of 0.2 M to 2.0 M in a
multi-solvent organic electrolyte system over a wide temperature range –40°C to 60°C are reported.
The mixed solvents used were 1, 3-dioxolane (DOL), 1, 2-dimethoxyethane (DME), and tetraethylene
glycol dimethyl ether (TEGDME) with an equal ratio of DOL: DME: TEGDME (1:1:1 by volume). The
experimental analysis performed over the wide temperature range revealed the maximum conductivity
at salt concentrations ranging from 1.0 M to 1.4 M for equal molar solvents. The optimum salt
concentration and maximum conductivity in a different solvent composition ratio (i.e., 3:2:1) for all the
temperatures is reported herein. The temperature-dependence conductivity of the salt concentration
did not fit the Arrhenius plot but it resembled the Vogel-Tamman-Fulcher plot behaviour. The present
conductivity study was carried out to evaluate the overall operable temperature limit of the electrolyte
used in the lithium-sulfur battery.