to represent various components of the cell: the interface between the current collector and the electrode Γ c , the interface between the membrane and the electrode Γ m , the inlet boundary Γ in where the electrolyte enters the inlet channel, the outlet boundary Γ out where the electrolyte exits the outlet channel, and the rest of the boundaries grouped into the wall edge (Γ w ). The investigated 2D geometries in the current study are a diagonal cross-section of the full 3D domain, depicted as a gray plane in Fig. .