To answer this question, we have computed the Poisson potential of liquid phase from both DFT and point-charge models for the same configurations of LiCl electrolyte solutions as a function of salt concentration. The results are shown in Fig. . In the case of neat liquid water, we got the Poisson potential of 3.49 V with the DFT model (BLYP) and that of -0.86 V with the point-charge model (SPC/E water + JC ions). They agree very well with the literature values for both types of descriptions, 3.49 V 35 and -0.84 V 37 respectively.