Effects of Carbon Dioxide on the Performance of Anion-Exchange Membrane Fuel Cells

• Published in: Denki kagaku oyobi kōgyō butsuri kagaku Vol. 79; no. 5; pp. 322 - 325
• Main Authors: Inaba, M, Matsui, Y, Saito, M, Tasaka, A, Fukuta, K, Watanabe, S, Yanagi, H
• Format: Journal Article
• Language: Japanese
• Published: 01.05.2011
• Subjects: Anodes; Carbon dioxide; Density; Electrodes; Fuel cells; Low currents; Membranes; Voltage
• DOI: 10.5796/electrochemistry.79.322
• ISSN: 1344-3542

The effects of CO sub(2) on the performance of an anion-exchange membrane fuel cell were investigated using a three-electrode single cell equipped with a reference electrode. Though the membrane resistance decreased at high current densities in the presence of CO sub(2) via the self-purging mechanism, the cell voltage was significantly lower than that for pure O sub(2) especially at low current densities even at a very low CO sub(2) concentration of 100 ppm. The overpotential at the cathode was hardly changed by the presence of CO sub(2), while that at the anode significantly increased in the presence of CO sub(2). It was concluded that carbonate/bicarbonate ions accumulated at the anode during operation, and reduces the ionic conductivity and the pH in the anode catalyst layer, which results in a high overpotential at the anode.