Alkaline fuel cells carbon dioxide, effect

While increasing intrinsic conductivity in anion exchange membranes is still focus of research, a major factor influencing effective conductivity is carbon dioxide (CO2). In contrast to alkaline fuel cells (AFCs) with liquid KOH electrolyte, in which carbonate precipitation occurs, in alkaline membrane fuel cells there is no place for salt precipitation, since in solid electrolytes there are no free cation species available for precipitation. However, CO2 still affects the alkaline membrane fuel cell general performance by decreasing the effective conductivity of the anion exchange membranes [15-18], as it is indicated below ... 

Al-Saleh, M. A., Gultekin, S., Al-Zakri, A. S., and Celiker, H. 1994. Effect of carbon dioxide on the performance of Ni/PTFE and Ag/PTFE electrodes in an alkaline fuel cell. Journal of Applied Electrochemistry 24 575-580. 

Although the harmful effects of carbon dioxide poisoning can be partly reduced by circulating the electrolyte as discussed by Cifrain et al. (2003b), a permanent solution must be sought for possible commercialization of alkaline fuel cell. 

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