The charge and electron-transport properties of molten ionic systems are among the most relevant properties to consider in the control of several electrochemical processes. First-principles-based equilibrium molecular dynamics (EMD) can provide reliable predictions of both total and partial charge-transport properties. In this work, we calculate the charge-transport properties of the electrolytic bath (Na3AlF6-AlF3 -Al2O3) of the Hall-Heroult electrolysis cells. We predict both individual and collective charge-transport properties (total and partial conductivities and self-diffusion coefficients) for 11 different compositions typical of industrial conditions via a series of EMD simulations. The predicted total and partial ionic conductivities and their composition dependence are compared to available experimental data. A good agreement is obtained for all studied compositions. From a more fundamental point of view, the microscopic aspect of the charge-transport properties of cryolitic melts is discussed through its correlation with the local structure of different melts. Deviations between the calculated partial conductivities and those derived via the Nernst-Einstein approximation can be explained by the presence of strong short-range ordering within the melts.