Development of direct ethanol fuel cell membrane electrode assemblies using sulfonated polyetheretherketone mixed-matrix membranes

In the framework of a project funded by the Fraunhofer Gesellschaft, a direct ethanol fuel cell has been developed. As part of the development, a new catalyst concept for the anodic oxidation of ethanol at an increased CO2 efficiency by using two different catalysts for two steps in the reaction process has recently been presented. Furthermore, new membranes based on an organic-inorganic mixed-matrix which exhibit reduced ethanol cross-over at an increased selectivity for water diffusion, have been developed. In this paper we will describe the developments which were made to integrate these two approaches into membrane electrode assemblies. The obtained membrane electrode assemblies showed better performance in a DEFC compared to membrane electrode assemblies using Nafion® 115, in particular at low temperature and low cathode airflow conditions which are typical for portable applications.