Structural electrodes made of reduced graphene oxide (rGO) and aramid nanofiber (ANF) are promising candidates for future structural supercapacitors. In this study, the influence of nanoarchitecture on the effective ionic diffusivity, porosity and tortuosity in rGO/ANF structural electrodes is investigated through multiphysics computational modeling. Two specific nanoarchitectures, namely, 'house-of-cards' and 'layered' structures are evaluated. The results obtained from nanoarchitecture computational modeling are compared to the porous media approach and shows that the widely used porous electrode theory such as Bruggeman or Millington-Quirk relations, overestimates the effective diffusion coefficient. Also, the results from nanoarchitecture modeling are validated with experimental measurements obtained from impedance spectroscopy (EIS) and cyclic voltammetry (CV). The effective diffusion coefficients obtained from nano-architectural modeling show better agreement with experimental measurements. Evaluation of microscopic properties such as porosity, tortuosity and effective diffusivity through both experiment and simulation is essential to understand the material behavior and improve its performance.