Nucleophilic substitution between polysulfides and binders unexpectedly stabilizing lithium sulfur battery

Nucleophilic substitution between polysulfides and binders unexpectedly stabilizing lithium sulfur battery

TitleNucleophilic substitution between polysulfides and binders unexpectedly stabilizing lithium sulfur battery
Publication TypeJournal Article
Year of Publication2017
AuthorsMin Ling, Liang Zhang, Tianyue Zheng, Jun Feng, Jinghua Guo, Liqiang Mai, Gao Liu
JournalNano Energy
Volume38
Pagination82 - 90
Date Published01/2017
ISSN22112855
Abstract

Polysulfide shuttling has been the primary cause of failure in lithium-sulfur (Li-S) battery cycling. Here, we demonstrate an nucleophilic substitution reaction between polysulfides and binder functional groups can unexpectedly immobilizes the polysulfides. The substitution reaction is verified by UV–visible spectra and X-ray photoelectron spectra. The immobilization of polysulfide is in situ monitored by synchrotron based sulfur K-edge X-ray absorption spectra. The resulting electrodes exhibit initial capacity up to 20.4 mAh/cm2, corresponding to 1199.1 mAh/g based on a micron-sulfur mass loading of 17.0 mg/cm2. The micron size sulfur transformed into nano layer coating on the cathode binder during cycling. Directly usage of nano-size sulfur promotes higher capacity of 33.7 mAh/cm2, which is the highest areal capacity reported in Li-S battery. This enhance performance is due to the reduced shuttle effect by covalently binding of the polysulfide with the polymer binder.

DOI10.1016/j.nanoen.2017.05.020
Short TitleNano Energy
Refereed DesignationRefereed