The ele- ments of the model are defined as follows: Ru is the uncompensated (electrolyte) resistance, Cdl – the double layer capacitance, and the Far- adaic contribution Rct is the charge transfer resistance due to the oxy- gen reduction reaction (ORR) and Rads and Cads are the elements accounting for the possible specific quasi‐reversible adsorption of the sulfonate‐groups of Nafion at the Pt‐electrocatalyst surface, which has a relatively small but not negligible influence on the impedance response.