The notable accumulation of NO3 -anions and remarkable decrease of DME molecules at the positively polarized LiCoO2 indicate a competition between NO3 -entering and DME leaving from the inner layer of EDL. The accumulation of NO3 -anions reduces the number of DME molecules, because the occupation of NO3 -ions with their associated Li + ions squeezes out DME on the cathode (Figures and, and Figure ). These results provide a qualitative picture: at the cathode surface, the added NO3 -anions associated with more Li + ions occupy the space of the inner layer of EDL, minimizing the solvent decomposition, as schematized in Figure and.