Optimizing membrane pretreatment for improved performance of anion exchange membrane-unitized regenerative fuel cells

• Published in: Journal of applied electrochemistry 2024, Vol.54 (1), p.53-63
• Main Authors: Rana, Md. Masud, Rajkumar, Palanisamy, Kang, Beom-Soo, Park, Gyungse, Sun, Ho-Jung, Kim, So Yeon, Lee, Hong-Ki, Shim, Joongpyo
• Format: Article
• Language: English
• Subjects: Anion exchanging; Chemistry; Chemistry and Materials Science; Deionization; Electrochemistry; Electrolytic cells; Fuel cells; Hydroxyl ions; Industrial Chemistry/Chemical Engineering; Isopropanol; Membranes; Optimization; Physical Chemistry; Pretreatment; Regenerative fuel cells; Research Article
• ISSN: 0021-891X; 1572-8838
• DOI: 10.1007/s10800-023-01950-8

Anion exchange membranes (AEMs) play a critical role in anion exchange membrane-unitized regenerative fuel cells (AEM-URFCs). In this study, we investigated the effect of different membrane treatment processes on the performance of AEM-URFCs. By replacing bromide ions (Br − ) with hydroxyl ions (OH − ), we were able to greatly enhance cell performance. We treated a membrane electrode assembly (MEA) with KOH solutions of varying solvents and concentrations, which caused the AEM to swell and replace Br − ions with OH − ions. We found that the concentration of OH − ions in the KOH solution had a significant impact on Br − ion replacement. The MEA treated with 1.0 M KOH in a mixture of isopropyl alcohol (IPA) and deionized water (H 2 O) (25/75 vol%) had the lowest Br − ion content and exhibited a current density of 215.0 mA cm −2 at 0.5 V (fuel cell mode) and 65.0 mA cm −2 at 2.0 V (water electrolyzer mode). These findings can inform future research on AEM-based fuel cells and water electrolyzers by identifying an optimal membrane pretreatment process. Graphical abstract