題目:Supramolecular Perylene Bisimide-Polysulfide Gel Networks as Nanostructured Redox Mediators in Dissolved Polysulfide Lithium–Sulfur Batteries
作者:Peter D. Frischmann†, Laura C. H. Gerber†, Sean E. Doris†⊥, Erica Y. Tsai†, Frank Y. Fan‡, Xiaohui Qu§, Anubhav Jain§, Kristin A. Persson§, Yet-Ming Chiang‡, and Brett A. Helms*†
† The Molecular Foundry, Lawrence Berkeley National Laboratory, One Cyclotron Road, Berkeley, California 94720, United States
⊥ Department of Chemistry, University of California, Berkeley, California 94720, United States
‡ Department of Materials Science and Engineering, Massachusetts Institute of Technology, Cambridge, Massachusetts 02139, United States
§ Computational Research Division, Lawrence Berkeley National Laboratory, One Cyclotron Road, Berkeley, California 94720, United States
摘要: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 redox-active, 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.![大牛Yet-Ming Chiang最新鋰電力作(Chem Mater,2015年9月30日)]()
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