Sulfonated poly(ether-ether-ketone) membranes with intrinsic microporosity enable efficient redox flow batteries for energy storage
File(s)
Published version
Author(s)
Type
Journal Article
Abstract
Redox flow batteries (RFBs) are promising for long-duration grid-scale sustainable energy storage. The ion-exchange membrane is a key component that determines energy efficiency and cycling stability. However, it remains challenging to develop membranes with high ionic conductivity and high selectivity toward redox-active electrolytes. We report the development of ion-conductive polymer membranes with record-breaking energy efficiency. By incorporating triptycene into poly(ether-ether-ketone) and controlled sulfonation, the resulting intrinsically microporous polymer membranes form highly interconnected water channels that facilitate transport of charge-balancing ions, particularly hydroxide anions. These microporous membranes showed high ionic conductivity without compromising the selectivity toward redox-active species. The membranes enabled excellent performance in alkaline aqueous organic and zinc-iron flow batteries, demonstrating long-term stability, high power density, and an operational current density up to 700 mA cm−2. The membranes also improved performance in neutral pH aqueous RFBs with high capacity utilization and retention, enhanced energy efficiency, and boosted power density.
Date Issued
2025-02-19
Date Acceptance
2024-11-21
Citation
Joule, 2025, 9 (2)
ISSN
2542-4351
Publisher
Elsevier
Start Page
101795
End Page
101795
Journal / Book Title
Joule
Volume
9
Issue
2
Copyright Statement
© 2024 The Author(s). Published by Elsevier Inc. 1 This is an open access article under the CC BY license (http://creativecommons.org/licenses/by/4.0/).
License URL
Publication Status
Published
Article Number
101795
Date Publish Online
2024-12-19