Optimization of operating conditions of a mini fuel cell for the detection of low or high levels of CO in the reformate gas

A prototype of a miniaturized fuel cell has been studied in order to detect carbon monoxide in hydrogen-rich atmosphere for PEM-FC (Protonic Exchange Membrane fuel - cell) applications. It consists in a home-made Membrane–Electrode — Assembly (MEA) developed by the CEA. Experiments have been carried out on a laboratory testing bench with simulated reformed gases. For low CO concentrations (≤20 ppm), an amperometric mode is suitable but regeneration in air is necessary to obtain a good reversibility of the sensor response. On the contrary, for higher CO concentrations (250 to 4000 ppm), a good reversible response is observed without air regeneration by using a potentiometric or quasi-potentiometric mode. Therefore, this prototype of mini CO sensor seems to be convenient for monitoring reformed gases and ensures the correct operation of a PEM-FC.