the structure of the electrical double layer (edl) formed by solvated ions near a metal surface was studied by monte carlo simulations using an improved primitive model. the proposed model, which includes different radius and adsorption potentials for each solvating atmosphere, was applied to the interfacial system ni(111)-nicl2 (aqueous). model results show oscillations in the profiles of density and potential, and the separation and reversal of the charge in the edl. additionally, the model shows a prevalence effect of ions size over the asymmetric charge effect, producing a positive potential of zero charge (pzc) for the studied system, although the adsorption of the hydrating atmosphere of anions is more favorable than that of cations. these structural characteristics of the edl are very different from those found with simple primitive models, restricted or not.