Modulating the electrode pore structure using the magnetic field for reduced local-oxygen transport resistance in polymer electrolyte membrane fuel cell

Abstract

We utilize a magnetic field to align the pore structure of the PEMFC cathode catalyst layer in the direction of O2 infiltration. This alignment reduces the oxygen diffusion resistance within the catalyst layer, thereby augmenting the performance of the PEMFC. Membrane Electrode Assemblies (MEAs) with magnetically aligned cathodes demonstrate a 50% reduction in O2 transfer resistance compared to conventional MEAs, as verified through electrochemical experiments and it makes a performance enhancement in the I-V curve. Beyond electrochemical experimentation, electrode pore analysis utilizing 3D reconstruction and Lattice Boltzmann Direct Numerical simulation (LB-DNS) for internal flow field analysis within pores, reveals that alignment of the electrode structure in the through-plane direction enhanced pore continuity. This continuity and the resultant minimized proportion of dead pores are identified as the causative factors for the observed performance improvements.