Results in Fig. were generated using the model system shown in Fig. ). The unit cell had linear dimensions (38.35 × 40.20 × 173.70) A. The electrolyte region was 150 A in length (along the C-dimension) and contained 1850 EC molecules and 140 Li + / PF - 6 ion pairs, again using a 1 M salt concentration. The anode was comprised of 12 graphene layers of 3.35 A spacing (corresponding to pure graphite). The reduced spacing was to prevent intercalation of species into the anode. NVT-MD equilibration length was 5 ns.