The parameter τ indicates the ratio of electrolyte/electrode conductivity. Having the ohmic losses artificially fixed via setting a constant value of 1.0 for the parameter δ determining the ratio of ohmic to kinetic resistance, τ can be seen as the parameter controlling the preferred phase for the optimization algorithm to reduce the ohmic losses in the applied operating conditions. The combination of δ and τ controls how the ohmic losses get reduced by placing the more conductive phase closer to the membrane where the electrochemical performance is measured in this study. The dominance of the liquid or solid phases can be determined based on the definition of the effective conductivities (Eqs. and the penalized porosity in Eq. 42. For higher τ values, the ionic conductivity in the liquid-only phase (γ = 0) will be closer to the electronic conductivity in the pure solid phase (γ = 1), meaning that the addition of the electrolyte close to the membrane can lead to increasing the ionic current and reducing the ohmic losses. As can be observed in Fig. , the τ parameter affects the electrochemical performance metric such that it becomes negative when there is a low preference on the electrolyte phase, meaning the theoretical ohmic losses increase after the optimization in comparison to a uniform-porosity electrode.