The voltage current curve of a PEM fuel cell: Analytical and numerical modeling

The formulas for polarization voltage of the cathode catalyst layer of a PEM fuel cell are obtained. Based on these formulas, the fitting equation for the voltage current curve of a cell is constructed. The terms of this equation have clear physical meaning; the coefficients are expressed in terms of basic transport and kinetic parameters of a cell. The equation is then used to fit experimental voltage current curve and to estimate the parameters of the real cell. With this set of parameters a quasi-3D simulation of the cell is performed. Comparison of simulated, experimental and analytical voltage current curves allows to isolate the contribution of 2D effects to cell performance. This combination of analytical and numerical models enables to characterize membrane-electrode assemblies and flow fields using experimental voltage current curves.