Modeling the Effect of Low Pt Loading Cathode Catalyst Layer in Polymer Electrolyte Fuel Cells. Part II: Parametric Analysis

A parametric analysis is presented using a previously validated 1D model for cathode catalyst layer (CL). The results show that maximum power density at low Pt loading can be maximized with relatively thin CLs (thickness ∼ 2 μ m) featuring high carbon volume fraction (low ionomer-to-carbon weight ratio, I/C) compared to CLs. shift of the optimal (I/C ratio) caused by dominant role local oxygen transport resistance loading, which lowered reduction average ionomer film thickness (better distribution among particles). In contrast, higher porosity and pore radius (lower fraction) beneficial due an increase bulk effective diffusivity despite thickening films. Moreover, performance significantly improved increasing mass-specific activity. effect saturation permeability on lower dry CL composition