Mapping the humidification range of a single PEM fuel cell

A test is conducted on a SO cm single fuel cell to map the operational range for the optimal humidification of PEM membrane. A major challenge to the optimum operation of a proton exchange membrane (PEM) fuel cell lies in maintaining a certain humidification level of the electrolyte. For an optimal operation of a solid polymer fuel cell, correct humidification level of the membrane is desired to enable proton conductivity and prevent drying out with the consequent loss of fuel cell power. On the contrary, if the membrane is over humidified, the cell will flood - a condition in which the humidifying fluid blocks the flow of the reactants to the catalyst sites. To maintain an optimal operation range, a test is conducted at various temperatures, flow rates, current densities and stoichiometry with the intent of mapping the operational range of a 50 cm2 proton exchange fuel cell with an externally mounted humidifier. The result reveals that a dew point temperature range of 65degC presents an acceptable range for the membrane tested. This report focuses on humidification of a single cell, using NAFIONtrade 111 membrane, with air and hydrogen as reactant gases, an external humidification system with the objective of finding the optimal operational range for the cell.