Select sensitivity parameters for proton exchange membrane fuel cell model: An identification method from analytical Butler-Volmer equation

The highly coupled nature of the reaction process and the multitude of model parameters in proton exchange membrane fuel cell pose significant challenges in establishing a high-confidence and high-precision model. In this paper, a multi-physics model is developed, which couples electrochemical reactions, multiphase water conversion, together with mass and charge transport processes. Through single-factor sensitivity analysis involving physical, mass transfer, heat transfer, and electrochemical parameters, seven sensitive parameters with their overlapping relationships related to open circuit voltage loss, activation loss, and ohmic loss under both low and high current densities have been identified. A detailed model parameter identification method specifically designed for low current densities is proposed based on parameter decoupling and the analytical Butler-Volmer equation. Finally, polarization curve and ohmic impedance experiments are conducted using a proton exchange membrane fuel cell with single serpentine flow channel at various temperatures and pressures to obtain voltage losses for parameter identification. The results show that the maximum relative error in the polarization curves is 2.08% with an average relative error of 0.81% under different conditions, thus validating the effectiveness of the proposed method.