The jellium/hard sphere electrolyte model for the electric double layer is reconsidered and extended in several ways. The effect of various approximations for the electronic density profile on the calculated capacity values is investigated. On the whole, the new calculations, which are performed with a higher accuracy, confirm our previous results. A heuristic formula for the dielectric response of the ensemble of hard spheres to high electric fields is presented; capacity-charge characteristics calculated from this formula show a capacity maximum close to the potential of zero charge. The dipole potential at the uncharged interface is also calculated; its variation with the metal agrees well with the values derived by Trasatti from experimental data. © 1986 American institute of Physics.