Advanced Reversal Tolerant Anode in Proton Exchange Membrane Fuel Cells: Study on the Attenuation Mechanism during Fuel Starvation.

Abstract

Fuel starvation at the anode of a proton exchange membrane fuel cell can lead to the increase of anode potential and the reversal of cell voltage followed by water electrolysis and carbon corrosion. A material-based approach (with high active water electrolysis catalysts) does not have much influence on the electrochemical performance, and carbon corrosion can be effectively avoided compared with the complex active control system. However, the membrane electrode assembly shows poor reversal tolerant performance during the hydrogen starvation test in previous studies, and the degradation mechanism is unclear. Therefore, reversal tolerant anode electrodes are designed in this article, and the voltage decrease mechanism is investigated comprehensively. The results exhibit that the increase of anode potential is mainly caused by the increase of mass transport resistance. Additionally, the voltage reversal time can be up to 5020 min, and the degradation rate of cell voltage at 1.2 A cm-2 can be as low as 0.12% h-1 after the first fuel starvation test.