Alkaline membrane fuel cell (AMFC) modeling and experimental validation

This paper aims to produce a dynamic model that is computationally fast to predict the response of the single AMFC according to variations of physical properties of the materials, and operating and design parameters. The model is based on electrochemical principles, and mass, momentum, energy and species conservation. It also takes into account pressure drop in the gas channels and the temperature gradient with respect to space in the flow direction. The simulation results comprise temperature distribution, net power and polarization curves, which were experimentally validated by direct comparison to voltage and current measurements performed in a cellulose-based AMFC prototype for different electrolyte (KOH) solution concentrations (y), showing good quantitative and qualitative agreement. It is concluded that the startup transient is short and that there are optimal values of y (∼40 wt. % ) which lead to maximum power, that are herein shown experimentally for the first time. In the process, the model was used to formulate empirical correlations for the exchange current density (i0) in the electrodes with respect to the electrolyte concentration for future fuel cell development. Therefore, the adjusted and validated model is expected to be a useful tool for AMFC control, design and optimization purposes.