Optimization of a PEM fuel cell operating conditions: Obtaining the maximum performance polarization curve

This work presents the operating conditions optimization of a 50 cm2 PEM fuel cell using a one dimensional analytical model previously validated against experimental data for a comprehensive set of different operating conditions of cell temperature, pressure, reactants relative humidity and cathode stoichiometry. The analytical model is used to predict the operating conditions that provide the maximum (and the minimum) power output of the given PEM fuel cell for every value of current intensity. Thus, a maximum performance polarization curve is developed where the operating conditions are not fixed for every current intensity, but modified in order to provide the maximum possible power output for every value of current intensity. The obtained operating conditions have been tested in the real cell showing a good agreement between experimental and modeling results where the maximum error is below 2% for the case of maximum power and 3% for the case of minimum power. The comparison shows that the power output using the operating conditions for the curve of maximum power is about 100% higher than using the curve of minimum power.