Here Formation Energy (eV/f.u) Content (α) Furthermore, we calculated the binding energy of Li/Mg ions as a function of ion content using Eq. 4 as shown in Fig. . It is clear that the binding energy rises when the ion content increases. This is mainly due to the enhanced repulsion between the ions when multiple ions are adsorbed on the monolayers. Both Li adsorbed Ti 2 CSO, and Ti 2 CSSe MXenes provide lower binding energies compared to that of Mg adsorbed counterparts. Those results agree with the formation energies calculated by cluster expansion, where the Li-based electrodes provided lower values compared to that from the Mg-based electrodes. Thus, we can expect the high stability of Li relative to Mg on those nanosheets.