Parameterization and Validation of a 2-Dimensional, Transient, Two-Phase MEA Model Capable of Simulating Electrochemical Impedance Spectra

Abstract

Proton exchange membrane fuel cells (PEMFC) are promising energy converters, offering both sustainability and efficiency. Achieving optimal performance, however, requires a deep understanding of the underlying cause-effect relationships within the functional layers. One effective approach for validating models that capture the complex physics of PEMFC is through differential cells, which reduce computational effort by allowing along-the-channel-effects to be discarded [1,2].In this study, we present a 2-dimensional, transient, non-isothermal PEMFC model that enables the disentanglement of loss contributions, facilitating effective material screening. Our model accounts for multiphase transport to provide insights into water management and mass transport. To ensure robust parameterization, we conducted a multitude of both ex-situ and in-situ experiments, reducing our reliance on often-contradictory literature data [3].We fitted our model to a wide range of polarization curves obtained under operating conditions spanning temperatures of 50-80 °C and relative humidities of 40-100 %. Notably, our model is able to simulate impedance spectra, which enables the disentanglement of processes with different time constants [4]. This approach provides a unique opportunity to study the electrochemical behavior and offers a more profound understanding of PEMFC performance limitations. The thorough parameterization process and validation against a broad range of operating conditions and impedance spectra render our model reliable and effective for industry professionals and researchers. We also highlight shortcomings and physics aspects that require further research to deepen insights and enable faster industrialization cycles.