Study on Commercially Available Membranes for Alkaline Direct Ethanol Fuel Cells

Michaela Roschger; Sigrid Wolf; Andreas Billiani; Kurt Mayer; Maša Hren; Selestina Gorgieva; Boštjan Genorio; Viktor Hacker

doi:10.1021/acsomega.3c01564

Study on Commercially Available Membranes for Alkaline Direct Ethanol Fuel Cells

ACS Omega. 2023 Jun 2;8(23):20845-20857. doi: 10.1021/acsomega.3c01564. eCollection 2023 Jun 13.

Authors

Michaela Roschger¹, Sigrid Wolf¹, Andreas Billiani¹, Kurt Mayer¹, Maša Hren², Selestina Gorgieva², Boštjan Genorio³, Viktor Hacker¹

Affiliations

¹ Institute of Chemical Engineering and Environmental Technology, Graz University of Technology, Inffeldgasse 25/C, 8010 Graz, Austria.
² Faculty of Mechanical Engineering, University of Maribor, Smetanova Ulica 17, 2000 Maribor, Slovenia.
³ Faculty of Chemistry and Chemical Technology, University of Ljubljana, Večna Pot 113, 1000 Ljubljana, Slovenia.

Abstract

This study provides a comparison of different commercially available low-cost anion exchange membranes (AEMs), a microporous separator, a cation exchange membrane (CEM), and an anionic-treated CEM for their application in the liquid-feed alkaline direct ethanol fuel cell (ADEFC). Moreover, the effect on performance was evaluated taking two different modes of operation for the ADEFC, with AEM or CEM, into consideration. The membranes were compared with respect to their physical and chemical properties, such as thermal and chemical stability, ion-exchange capacity, ionic conductivity, and ethanol permeability. The influence of these factors on performance and resistance was determined by means of polarization curve and electrochemical impedance spectra (EIS) measurements in the ADEFC. In addition, the influence of two different commercial ionomers on the structure and transport properties of the catalyst layer and on the performance were analyzed with scanning electron microscopy, single cell tests, and EIS. The applicability barriers of the membranes were pointed out, and the ideal combinations of membrane and ionomer for the liquid-feed ADEFC achieved power densities of approximately 80 mW cm^-2 at 80 °C.