Numerical Simulation of the Power Performance a Proton Exchange Membrane Fuel Cell Under Dynamic Loading Conditions

Proton exchange membrane fuel cell (PEMFC) is an ideal form of power generator, but its performance is drastically compromised under dynamic loading conditions. For the purpose of correctly understanding and accurately predicting the power performance of PEMFC under dynamic loading conditions so as to facilitate the rational design of PEMFC vehicles, this paper first built a high-fidelity 3D model of a PEMFC, then precisely calculated the dynamic voltage response during the non-steady stages, and finally identified the influential factors that can moderate the dynamic response. Results suggest that avoiding extremely large rate of current density change can keep the PEMFC running in steady state, which is beneficial to the lifetime of the PEMFC. Meanwhile, raising the anode/cathode pressure to 2.0 atm, maintaining the excess H2/O2 coefficients above 2.0/2.5, or keeping the anode/cathode inlet sufficiently humidified to 100% R.H. help the PEMFC to quickly reach new equilibrium in response to dynamic loading. The novelty of this paper is embedded in the detailed modeling of the PEMFC micro structure as well as the systematic parametric analysis of the potential moderating factors and mechanisms of the dynamic response.