In this work, we build on the work presented recently on the development of a unified formulation across the electrode-electrolyte-electrode system using a rigorous volume averaging approach typical of multiphase formulation. In this method, we have a unified, singledomain approach where complex geometries are naturally incorporated with the numerical algorithms guaranteeing stability and convergence. These contrast with models based on a segregated formulation with intermediate boundaries. This uniform formulation applies to 1D, 2D and 3D geometries irrespective of the complexities associated with dimensionality as well as with electrode/electrolyte spatial arrangements. In addition, the formulation accounts for any spatio-temporal variation of the different properties such as electrode/void volume fractions (see Fig. 1) and anisotropic conductivities. This generality is exploited to upscale local properties directly into the mesoscopic model with the aid of detailed characterization of the electrode/separator material as well as the direct numerical simulations to resolve the electrode/separator and electrolyte interfaces.