We now argue that the free energies obtained in the implicit solvent are consistent with than the Sys. I i setup (1 TBT) (Fig. ). Also, the minimum of the free energy decreases with decreasing the dielectric constant as summarized in Table . These results confirm that Li + -π interactions are stronger than the π -π interactions, causing Li + ion to insert itself between the π -π bonds of benzene-benzene and thiophene-thiophene. In summary, the magnitude of the binding free energy in the implicit solvent is consistent with the magnitude of the binding energy in the gas phase considering the dielectric screening of the medium as well as entropic effects. Moreover, the magnitude of the binding free energy can be tuned by altering the dielectric constant of the medium, providing a means to control and tune the interaction strength between the TBT monomer and Li + ion. However, a direct comparison of the predicted binding free energies for TBT and its oligomer in solution to the experiment is very difficult, because the latter is hard to measure. In the future, we plan to connect to well-controlled experiments, e.g., simple adsorption of the Li + ions at the TBT or PTBT cathode -in a dilute polymer solution or dense electrodes -with which one could estimate the binding energies.