%0 Journal Article
%A Peter D Frischmann
%A Laura C. H Gerber
%A Sean E Doris
%A Erica Y Tsai
%A Frank Y Fan
%A Xiaohui Qu
%A Anubhav Jain
%A Kristin A Persson
%A Yet-Ming Chiang
%A Brett A Helms
%B Chemistry of Materials
%D 2015
%G eng
%N 19
%P 6765 - 6770
%R 10.1021/acs.chemmater.5b02955
%T Supramolecular Perylene Bisimide-Polysulfide Gel Networks as Nanostructured Redox Mediators in Dissolved Polysulfide Lithium–Sulfur Batteries
%V 27
%8 10/2015
%! Chem. Mater.
%X <p>Here we report a new redox-active perylene bisimide (PBI)- polysulfide (PS) gel that overcomes electronic charge-transport bottlenecks common to lithium−sulfur (Li−S) hybrid redox flow batteries designed for long-duration grid-scale energy storage applications. PBI was identified as a supramolecular redox mediator for soluble lithium polysulfides from a library of 85 polycyclic aromatic hydrocarbons by using a high-throughput computational platform; furthermore, these theoretical predictions were validated electrochemically. Challenging conventional wisdom, we found that π-stacked PBI assemblies were stable even in their reduced state through secondary interactions between PBI nanofibers and Li2Sn, which resulted in a redoxactive, flowable 3-D gel network. The influence of supramolecular charge-transporting PBI-PS gel networks on Li−S battery performance was investigated in depth and revealed enhanced sulfur utilization and rate performance (C/4 and C/8) at a sulfur loading of 4 mg cm−2 and energy density of 44 Wh L−1 in the absence of conductive carbon additives.</p>