Effect of operating conditions on carbon corrosion in polymer electrolyte membrane fuel cells

The influence of humidity, cell temperature and gas-phase O2 on the electrochemical corrosion of carbon in polymer electrolyte membrane fuel cells is investigated by measuring CO2 emission at a constant potential of 1.4 V for 30 min using on-line mass spectrometry. Carbon corrosion shows a strong positive correlation with humidity and cell temperature. The presence of water is indispensable for electrochemical carbon corrosion. By contrast, the presence of gas-phase O2 has little effect on electrochemical carbon corrosion. With increased carbon corrosion, changes in fuel cell electrochemical characteristics become more prominent and thereby indicate that such corrosion significantly affects fuel cell durability.