A class of polysulfide catholytes for lithium–sulfur batteries: energy density, cyclability, and voltage enhancement
- 28 November 2014
- journal article
- research article
- Published by Royal Society of Chemistry (RSC) in Physical Chemistry Chemical Physics
- Vol. 17 (3), 2127-2136
- https://doi.org/10.1039/c4cp04895d
Abstract
Liquid-phase polysulfide catholytes are attracting much attention in lithium–sulfur (Li–S) batteries as they provide a facile dispersion and homogeneous distribution of the sulfur active material in the conductive matrix. However, the organic solvents used in lithium–polysulfide (Li–PS) batteries play an important role and have an impact on the physico-chemical characteristics of polysulfides. For instance, significantly higher voltages (∼2.7 V) of the S/Sn 2− (4 ≤ n ≤ 8) redox couple are observed in Li–PS batteries with dimethyl sulfoxide (DMSO) and N-methyl-2-pyrrolidone (NMP) solvents. Accordingly, high power Li–PS batteries are presented here with the catholyte prepared with NMP solvent and operated with the highly reversible sulfur/long-chain polysulfide redox couple. On the other hand, a remarkable cyclability enhancement of the Li–PS battery is observed with the long-chain, ether-based tetraglyme (TEGDME) solvent. The voltage enhancement and the cyclability enhancement of the Li–PS batteries are attributed to the solvation effect, viscosity, and volatility of the solvents. Finally, highly concentrated polysulfide catholytes are successfully synthesized, with which high energy density Li–PS batteries are demonstrated by employing a multi-walled carbon nanotube (MWCNT) fabric electrode.Keywords
Funding Information
- Advanced Research Projects Agency - Energy (DE-AR0000377)
This publication has 41 references indexed in Scilit:
- Sulfur‐Infiltrated Micro‐ and Mesoporous Silicon Carbide‐Derived Carbon Cathode for High‐Performance Lithium Sulfur BatteriesAdvanced Materials, 2013
- Role of LiNO3 in rechargeable lithium/sulfur batteryElectrochimica Acta, 2012
- Lithium/Sulfur Cell Discharge Mechanism: An Original Approach for Intermediate Species IdentificationAnalytical Chemistry, 2012
- Self-weaving sulfur–carbon composite cathodes for high rate lithium–sulfur batteriesPhysical Chemistry Chemical Physics, 2012
- Electrochemistry of Sulfur and Polysulfides in Ionic LiquidsThe Journal of Physical Chemistry B, 2011
- Li/S fundamental chemistry and application to high-performance rechargeable batteriesSolid State Ionics, 2004
- In Situ Spectroelectrochemical Studies on the Reduction of Sulfur in Dimethyl Sulfoxide SolutionsJournal of the Electrochemical Society, 1993
- Electrochemical Reduction of Elemental Sulfur in AcetonitrileBulletin of the Chemical Society of Japan, 1980
- Electrochemical reduction of sulfur in aprotic solventsInorganic Chemistry, 1973
- Spectrophotometric study of the electrochemical reduction of sulphur in organic mediaJournal of the Chemical Society, Chemical Communications, 1972