Graphene Nanoplatelets: Characteristics of a Graphene Nanoplatelet Anode in Advanced Lithium‐Ion Batteries Using Ionic Liquid Added by a Carbonate Electrolyte (Adv. Mater. Interfaces 8/2015)

High Voltage Li-Ion Battery Using Exfoliated Graphite/Graphene Nanosheets Anode

“…This extra capacity may be efficiently mitigated both chemically, i.e., by lithium−metal surficial treatment of the electrode, and electrochemically by precycling, as already demonstrated in previous reports. 39,41 Figure 2c reveals a capacity value about 40% higher for the EGNs electrode with respect to BG delivered, in addition, at higher current rate (i.e., 2C with respect to 0.2C). Indeed, the presence of graphene layers, the edge-lithium storage, and the particular morphology of the EGNs electrode allows the uptake of an extra lithium amount 41 with respect to BG, thus leading to a higher capacity and rate capability of the material here proposed and well compensating the relatively higher working voltage observed in Figure 2a.…”

“…with a specific capacity of 372 mAh g −1 Instead, graphene, which may accommodate lithium in two sides of the carbon layer, electrochemically reacts following the mechanism 39,41…”

“…Instead, graphene, which may accommodate lithium in two sides of the carbon layer, electrochemically reacts following the mechanism , with a specific capacity of 744 mAh g –1…”

“…Graphene and graphene oxide-based anodes have been widely explored in lithium half-cell, revealing a stable capacity ranging from 800 to 300 mAh g –1 . − However, only few works demonstrated the suitability of this material in replacement of the Li-anode in Li-full cell. − This is mainly due to the poor loading of graphene-based electrode that leads to severe issue during cell assembly and scaling up, mainly ascribed to very difficult N/P ratio setting. Herein we developed a EGNs electrode of satisfactory mass density leading to enhanced performance in half-cell, with reversible capacity of about 500 mAh g –1 , as well as to a successfully balanced full cell having remarkable cycle life and efficiency.…”

“…Lian and co-workers demonstrated that few curled layers of graphene deliver a reversible capacity of about 800 mAh g –1 for 40 cycles using a current of 100 mA g –1 . Graphene may theoretically store higher lithium amount in comparison to graphite, thus leading to a theoretical specific capacity ranging from 744 mAh g –1 to 1448 mAh g –1 , depending on the graphene-based electrode morphology. − Indeed, lithium may bond graphene sheet sides as well as edges and covalent sites . Accordingly, recent studies demonstrated that the small lateral sizes of narrow graphene nanoribbons (e.g., nanoflakes) can actually accommodate Li + ions at the edges sites more efficiently than basal sites, thus leading to maximum Li storage of Li 4 C 6 with corresponding theoretical specific capacity of 1488 mAh g –1 .…”