Enduring Anion-Exchange Membrane Fuel Cells

Abstract

Alkaline anion exchange membrane fuel cells have become a topic of substantial interest in recent years, opening up a new electrochemical environment for hydrogen fuel cells. Facile kinetics for the oxygen reduction reaction open the promise of non-PGM or even non-metal AEMFCs, and radical stability. The most challenging aspect for the field, as defined by the 2016 DOE AMFC III Workshop, is membrane and ionomer stability in alkaline conditions at elevated operating temperatures. Few papers report endurance data, and best practices for in situ fuel cell conditioning and electrochemical characterization are still being developed by the community. Here, we report that HMT-PMBI exhibits membrane and ionomer stability in situ as AEMFCs in relevant conditions for device operation. These fuel cells demonstrate re-equilibration from extensive carbonation and complete re-conditioning in a shut-down / start-up cycle. We further report operation in typically challenging conditions, e.g. increased temperature and reduced humidity. Finally, we report on our attempts to define best-practices for electrochemical characterization.