Study of Alkaline Electrodes for Hybrid Polymer Electrolyte Fuel Cells

Hybrid polymer electrolyte fuel cells combine a proton exchange membrane (PEM) and anion exchange membrane (AEM) and exhibit unique advantages. The electrochemical performance and current limitations of a hybrid cell with an alkaline electrode fabricated on a Nafion membrane was characterized at 70 degrees C as a function of relative humidity. To separate the individual characteristics of the AEM anode and cathode electrodes, two semihybrid cell configurations, each with an AEM and PEM electrode, were constructed and compared to a conventional PEM fuel cell. Electrochemical impedance spectroscopy was used to diagnose the cell component characteristics. In particular, low catalyst utilization in the AEM electrode was a primary factor in the performance losses in the hybrid cells. (C) 2010 The Electrochemical Society. [DOI: 10.1149/1.3468700] All rights reserved.