Starting from the initial configuration of the pure EC system, we can see that the products concentration is steeply increased within the first stage of ∼ 10 -2 ns to reach a flat profile at longer times. The flattening of the profile after the initial stage is indicative of the onset of a regime where no valid reactive Li + /EC clusters are found and the reactive clusters need to be reactivated through diffusive processes. The two conditions for the occurrence of the first reduction reaction consist of one EC located within a distance of 1 nm from the electrode surface and one Li + coordinating to that EC. Since the number of EC molecules adsorbed at the electrode surface was only slightly changed due to the reactions, the rate limiting process for the first reduction corresponds to the coordination of Li + to EC and therefore also the flux of Li + from the bulk electrolyte to the reaction volume. We remark that for a diffusion constant of D = 5 × 10 -5 nm 2 ps and a time window of T = 1 ns the displacement of Li + should be expected to be within the range of 1 nm, thus the diffusive flux of Li + into the reaction volume is not expected to contribute significantly to the reactivation of the EC reduction within the initial stage. Nevertheless, in Figure (a) we show that the Li + number within the half unit cell containing the reaction volume shows a clear increase as a function of time after the initiation of the first reaction. We interpret this as a migration of Li + to the electrode driven by the excess of the negative charge transferred to the EC molecules in the first reaction. Figure shows the time dependence of the electric charge within the reaction zone, indicating that the charge density within this region is initially decreased to negative values due to the reactions and then restored to charge-neutrality via the ionic flux. Thus, the transition from a high slope to a low slope in the turnover rate is characteristic of a transition from an activation limited to a diffusion or migration limited reduction kinetics. A further important observation is that the coordination of negatively charged cEC -radicals to Li + results in the formation of stable neutral and negatively charged (LiEC), (LiEC 2 ) -and (LiEC 3 ) 2-bidentate and tridentate geometries (see Supplementary Figure ) prior to the onset of the ionic flux of Li + to the electrode. Since these complexes hinder the coordination of further EC molecules to Li + , the formation of these stable geometries effectively results in a rate-limiting step prior to the onset of the Li + ionic flux to the electrode (see Figures ) and 11 (a)-(d)).