Advanced State-of-X diagnostics of proton exchange membrane fuel cells enabled by the multi-scale modeling framework

Simultaneous optimization of efficiency and durability of proton exchange membrane fuel cells (PEMFC) calls for advanced State-of-X (SoX) diagnostics. Novel SoX functionalities are made possible by the knowledge of internal states of PEMFCs and parameters associated with the rate and efficiency of reactions as well as of transport mechanisms. To address this challenging task, we propose innovative SoX diagnostics method based on a computationally efficient multi-scale simulation framework for PEMFCs, parameter identification techniques and methods for assessing uniqueness of parameter identification. Proposed state-of-the-art simulation framework incorporates advanced submodel on spatially resolved dynamics of liquid water and newly added submodel considering the impact of the gas crossover effects on mixed potentials. Results demonstrate capability of the innovative SoX diagnostics method to perform detailed diagnostics of internal states of the PEMFC and to pinpoint degradation-imposed variation of parameters which are interlinked with catalyst activity, membrane losses and gas diffusion layer losses.