Assessing carbon-based anodes for lithium-ion batteries: A universal description of charge-transfer binding

Abstract

Many key performance characteristics of carbon-based lithium-ion battery anodes are largely determined by the strength of binding between lithium (Li) and sp2 carbon (C), which can vary significantly with subtle changes in substrate structure, chemistry, and morphology. Here, we use density functional theory calculations to investigate the interactions of Li with a wide variety of sp2 C substrates, including pristine, defective, and strained graphene; planar C clusters; nanotubes; C edges; and multilayer stacks. In almost all cases, we find a universal linear relation between the Li-C binding energy and the work required to fill previously unoccupied electronic states within the substrate. This suggests that Li capacity is predominantly determined by two key factors -- namely, intrinsic quantum capacitance limitations and the absolute placement of the Fermi level. This simple descriptor allows for straightforward prediction of the Li-C binding energy and related battery characteristics in candidate C materials based solely on the substrate electronic structure. It further suggests specific guidelines for designing more effective C-based anodes. The method should be broadly applicable to charge-transfer adsorption on planar substrates, and provides a phenomenological connection to established principles in supercapacitor and catalyst design.

accepted by Physical Review Letters

References in corpus (3)

• Dielectric function, screening, and plasmons in 2D graphene
• Feasibility of Lithium Storage on Graphene and Its Derivatives
• Screening of Coulomb Impurities in Graphene

Cited by in corpus (4)

• Origin of low sodium capacity in graphite and generally weak substrate binding of Na and Mg among alkali and alkaline earth metals
• Self-optimizing layered hydrogen evolution catalyst with high basal-plane activity
• On the identification of pristine and defected graphene nanoribbons by phonon signatures in the electron transport characteristics
• Enhanced Li capacity in functionalized graphene: A first principle study with van der Waals correction