  Gas diffusion electrodes are commonly used in high energy density metal-air
batteries for the supply of oxygen. Hydrophobic binder materials ensure the
coexistence of gas and liquid phase in the pore network. The phase distribution
has a strong influence on transport processes and electrochemical reactions. In
this article we present 2D and 3D Rothman-Keller type multiphase
Lattice-Boltzmann models which take into account the heterogeneous wetting
behavior of gas diffusion electrodes. The simulations are performed on FIB-SEM
3D reconstructions of an Ag model electrode for predefined saturation of the
pore space with the liquid phase. The resulting pressure-saturation
characteristics and transport correlations are important input parameters for
modeling approaches on the continuum scale and allow for an efficient
development of improved gas diffusion electrodes.
