▎ 摘　　要

Battery manufacturers are driven by the need to produce batteries with high energy densities and faster charging. For batteries to deliver such demands one would require a combination of high-performance anode materials with next-generation liquid electrolytes. Anodes made of graphene hold immense promise for revolutionizing next-generation rechargeable Li/Na ion batteries. Although experiments have demonstrated the capability of graphene anodes, vacuum-based density functional theory (DFT) calculations predict pure graphene to perform poorly owing to limited intercalation and unsatisfactory diffusivity of Li/Na. In a battery, depending on the polarizability of the medium, the interactions between electrodes and metal atoms can vary which may affect performance. Herein, the effect the permittivity of liquid electrolytes on the performance of graphene-based Li/Na ion batteries was studied using implicit solvation DFT calculations. Binding energy between graphene and adatoms was found to monotonically increase with epsilon(r), even going from positive to negative, indicative of an energetically favorable intercalation and improved storage. Also, with epsilon(r) >= 11.5, diffusion of Li (Na) was found to increase dramatically by over 10(6) (2 x 10(2)) times relative to vacuum. These results provide insights into the operation of graphene-based ion batteries and provide guidelines for their design. (C) 2020 Elsevier Ltd. All rights reserved.