Cathode catalyst layers (CCLs) contribute to a major proportion, 30%–40%, of voltage losses in Polymer Electrolyte fuel cells (PEFC). The objectives of the present study are to investigate how the catalyst layer performance depends on electrostatic interaction between reacting protons and the charged metal phase and how these relations are affected by composition and microstructure of agglomerates. A model is developed to study oxygen reduction in catalyst layers based on a novel agglomerate microstructure with conical pores. The model consists of coupled relations for reactant transport, metal charging behaviour, and interfacial charge transfer kinetics, evaluated under steady state conditions. Results show an enhancement in the effectiveness factor of conical pores compared to cylindrical pores. Results of the model are evaluated by comparison with existing experimental data. The effectiveness factor calculated for catalyst layer is 3% which is comparable to existing experimental data.

This content is only available via PDF.
You do not currently have access to this content.