One of the advantages given by the DEIS approach is the possibility to dynamically observe the changes in the inhibition depending on the time and concentration of the inhibitor in the solution. The extracted values of the R1 parameter from the DEIS monitoring can be correlated with the instant concentration of the inhibitor in the examined solutions. Next, the comparison of these data in the solutions with and without the inhibitor at a given time point gives the basis to calculate IE and Pinh using Eqs. ( ) and ( ), respectively . The obtained IE and Pinh profiles are shown in Fig. . For all alloys, the IE values increased rapidly starting at low inhibitor concentrations and were almost constant (around 87 to 95%) after the concentration of the inhibitor in the solution was ca. 25 mM. The obtained IE profile clearly demonstrates the mathematical bias provided by this characteristic. Even though rather large differences are observed between the values of R1 in the inhibited and uninhibited solutions (Fig. ), IE profiles after ca. 25 mM of the inhibitor looked almost like a straight line. This was the main motivation to introduce the inhibition power Pinh in recent studies and to use this parameter in the present study. Opposite to the IE, the Pinh profile was dynamically changing responding to the rise of the inhibitor concentration in the solution (Fig. ). The difference in the profiles in Fig. clearly shows the usefulness of the inhibition power characteristics in the evaluation of the corrosion inhibitors. The maximum value of Pinh was ca. 12, 18, and 14 for AZ31-4Li, AZ31-8Li, and AZ31-12Li, respectively. The obtained results suggest rapid interaction of the inhibitor with the surface of AZ31-xLi Mg alloys.