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

Ravindar Dharavath; Ashwin Murali; Abdul Wasi Tarapathi; Balasubramanian Trichy Srinivasan; Rambabu Kammili

Ravindar Dharavath Power Supply Systems Lab, Research Centre Imarat, Hyderabad 500069, Telangana, India.
Ashwin Murali Power Supply Systems Lab, Research Centre Imarat, Hyderabad 500069, Telangana, India.
Abdul Wasi Tarapathi Department of Chemical Engineering, Manipal Institute of Technology, Manipal 576104, Karnataka, India.
Balasubramanian Trichy Srinivasan Power Supply Systems Lab, Research Centre Imarat, Hyderabad 500069, Telangana, India.
Rambabu Kammili Power Supply Systems Lab, Research Centre Imarat, Hyderabad 500069, Telangana, India.

Keywords: Low temperature conductivity, multi-solvent organic electrolyte, optimum salt concentration, Arrhenius plot, lithium-sulfur battery

Abstract

The conductivity of an electrolyte plays a significant role in deciding the performance of any battery over a wide temperature range from 40C to 60C. 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 40C to 60C 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.