Thin Film Composite Membranes with Regulated Crossover and Water Migration for Long‐Life Aqueous Redox Flow Batteries

• DOI: 10.1002/advs.202206888
• Publication Date: 2023-05-13T13:34:53Z
• Authors: Rui Tan; Anqi Wang; Chunchun Ye; Jiaxi Li; Dezhi Liu; Barbara Primera D...; Luke Petit; Zhiyu Fan; Toby Wong; Alberto Alvarez‐F...; Mate Furedi; Stefan Guldin; Charlotte E. Brea...; Peter A. A. Klusener; Anthony R. Kucernak; Kim E. Jelfs; Neil B. McKeown; Qilei Song
• Keywords: Thin-film composite membrane

Abstract Redox flow batteries (RFBs) are promising for large‐scale long‐duration energy storage owing to their inherent safety, decoupled power and energy, high efficiency, longevity. Membranes constitute an important component that affects mass transport processes in RFBs, including ion transport, redox‐species crossover, the net volumetric transfer of supporting electrolytes. Hydrophilic microporous polymers, such as polymers intrinsic microporosity (PIM), demonstrated next‐generation ion‐selective membranes RFBs. However, crossover redox species water migration through remaining challenges battery Here, a facile strategy is reported regulating enhancing cycling stability by employing thin film composite (TFC) prepared from PIM polymer with optimized selective‐layer thickness. Integration these PIM‐based TFC variety chemistries allows screening suitable RFB systems display compatibility between membrane couples, affording long‐life operation minimal capacity fade. Thickness optimization further improves performance significantly restricts selected systems.