The structure and energetics of Li atoms intercalated into a graphite lattice were investigated using Hartree-Fock calculations of clusters of LiC20 and Li2C32, with particular emphasis being placed on minima and saddle points of the potential energy surface. These results were used in a Monte Carlo simulation for the diffusion of lithium through a graphite lattice. The screened Coulomb interactions between the Li atoms and the energy barrier encountered at the surface could given rise to unusual concentration profiles, with a sharp maximum on the side where the Li atoms left the lattice

The Diffusion of Lithium through Graphite: a Monte Carlo Simulation Based on Electronic Structure Calculations. W.Lehnert, W.Schmickler, A.Bannerjee: Chemical Physics, 1992, 163[3], 331-7