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This content will become publicly available on September 9, 2026

Title: A polysulfide/ferricyanide redox flow battery with extended cycling
The inexpensive sulfur raw material is promising to enable cost-effective redox flow batteries for long duration energy storage. But the catastrophic through-membrane crossover of polysulfides remains a severe challenge resulting in irreversible performance degradation and short cycle life. In this work, we demonstrate that use of a permselective cation exchange membrane yields a two orders of magnitude enhancement in polysulfide retention compared to the benchmark Nafion membrane. Combined physico-chemical, spectroscopic, and microscopic analyses suggest more disordered sidechain structures, which lead to the more hydrophobic nature and smaller hydrophilic domains in the membrane. The microstructural features contribute to the effective mitigation of polysulfide crossover. As a result, the cycle life of polysulfide/ferricyanide flow cells is boosted over a substantially extended test time. This finding sheds light on the fundamental membrane factors that cause polysulfide permeation and can provide feasible directions in the development of permselective membranes for polysulfide flow batteries.  more » « less
Award ID(s):
2055222 2436843
PAR ID:
10653265
Author(s) / Creator(s):
 ;  ;  ;  ;  ;  ;  ;  ;  ;  ;  ;  
Editor(s):
Hagfeldt, Anders
Publisher / Repository:
Royal Society of Chemistry
Date Published:
Journal Name:
Journal of Materials Chemistry A
Volume:
13
Issue:
35
ISSN:
2050-7488
Page Range / eLocation ID:
29610 to 29620
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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