Influence of catalyst agglomerate internal structure on PEFC performance investigated by a multiscale numerical model

A multiscale modeling framework, which consists of catalyst agglomerate scale and fuel scale models, has been developed for polymer electrolyte fuel cells (PEFCs). The performance of the agglomerate model is numerically linked to the fuel cell model by employing an interpolation function that represents the performance of the agglomerate. This framework unlocks the restrictions associated with the conventional agglomerate PEFC model by allowing the user to freely investigate the impact of the structure and the composition of the catalyst agglomerate. Thus the impact of the internal structure of the catalyst agglomerate on the fuel cell performance has been investigated. The results have shown that the fuel cell performs better with catalyst agglomerates embodying "separate" active clusters and this impact becomes more profound as the size of the agglomerate increases. Also, it has been shown that the performance of the catalyst agglomerate becomes significantly better as the agglomerate size decreases. These outcomes and other outcomes have been presented and fully discussed.