Energy profiles and charge transfer in Li adsorption/desorption on/from various charged single layer graphene electrodes in various electrolytes are investigated by hybrid first-principles/continuum calculations. The critical values of excess charge density of graphene and Li, at and above the critical value Li adsorption switches to Li desorption, are - 0.87 vertical bar e vertical bar, 0 vertical bar e vertical bar, and 1.5 vertical bar e vertical bar per formula unit for pristine graphene (with formula unit Li1C32) in water, monovacancy graphene (MVSLG, Li1C31) in water and in CCl4, respectively. When moving from far away towards the MVSLG in water and CCl4 during adsorption, Li+ ion is gradually reduced to Li atom by charge transfer. (c) 2017 Elsevier Ltd. All rights reserved.