Lithium intercalation into bilayer graphene

Abstract

The real capacity of graphene and the lithium-storage process in graphite are two currently perplexing problems in the field of lithium ion batteries. Here we demonstrate a three-dimensional bilayer graphene foam with few defects and a predominant Bernal stacking configuration, and systematically investigate its lithium-storage capacity, process, kinetics, and resistances. We clarify that lithium atoms can be stored only in the graphene interlayer and propose the first ever planar lithium-intercalation model for graphenic carbons. Corroborated by theoretical calculations, various physiochemical characterizations of the staged lithium bilayer graphene products further reveal the regular lithium-intercalation phenomena and thus fully illustrate this elementary lithium storage pattern of two-dimension. These findings not only make the commercial graphite the first electrode with clear lithium-storage process, but also guide the development of graphene materials in lithium ion batteries.

Dynamic Covalent Synthesis of Crystalline Porous Graphitic Frameworks

“…At the same discharged state, a strong lithium-carbon peak at 284 eV in its C1s spectrum was also observed, which we attributed to Li intercalation in 2D graphenelike layered structure and interaction with carbon species (Figure S24). 30,31 These data strongly suggest that both Li-N binding and Li intercalation contribute to electrochemical lithium storage in PGF-1 ( Figure 4E). The low crystallinity of AP-1 results in less accessible Li-N binding sites and impedes Li intercalation, as suggested by the significantly lower Li-bound nitrogen peak at 397.9 eV in its XPS spectrum ( Figure 4F), which also correlates well with its high impedance and lower LIBs capacity.…”

A Zinc–Dual‐Halogen Battery with a Molten Hydrate Electrolyte

“…These observations indicate that the formation of halogen–GICs is more kinetically restricted that the deintercalation process. [ 19 ] Nevertheless, the apparent diffusion coefficient of halogens ( D x ) in the graphite electrode at various (de)intercalation states estimated from GITT and EIS is around 10 −11 to 10 −10 cm 2 s −1 , which are larger than D Li + in typical cathode materials such as LiFePO 4 (10 −13 to 10 −12 cm 2 s −1 ) and close to recent reported D PF6 − in graphite (Figure 3d and Figure S11, Supporting Information). [ 20 ]…”

Effects of lithium intercalation in twisted bilayer graphene

“…Based on their measurements, the authors of Ref. [16] infer a lithium intercalation process with identifiable steps at concentrations of Li 1 C 244 , Li 1 C 85 , Li 1 C 28 , and Li 1 C 12 , the latter corresponding to full intercalation. Our estimated concentration in the AA region of the twisted bilayer, namely Li 1 C 144 , is intermediate between the first two steps of the proposed process, which is to be expected due to the confining potential of the AA region which will act to concentrate the Li atoms more than in a uniform bilayer.…”