Understanding and the control of Li-ion (Li+) transport across the interface between the anode and solid electrolyte interphase (SEI) film or electrolyte is a key issue in battery electrochemistry and interface science. In this study, we investigated the structural, electronic and free energy properties of Li+ migration between a Li-intercalated graphite anode LiCx and Li2CO3 SEI film, by using ab initio molecular dynamics and free energy calculations. We compared three types of graphite edges: H-, OH- and mixed (H, OH, COOH)-terminations, and three cases of transferred Li-ions: Li+ constructing the SEI, excess Li+ and excess Li0 (excess Li+ + e- in anode).
View Article and Find Full Text PDFWe propose a new analysis technique for characterizing molecular interactions that combines an energy decomposition scheme, such as the Kitaura-Morokuma decomposition method, with energy density analysis, which partitions the total energy of the system into atomic contributions. The combined scheme, termed Interaction-EDA, enables us to estimate the local contribution of interaction energy components, such as electrostatic, exchange, polarization, and charge transfer. The evaluation of the local interaction energy is rather important in large systems.
View Article and Find Full Text PDFAdsorption of H2, C2H2, C2H4, and CO onto a Si(100)-(2x1) surface has been treated theoretically using Si(12n - 3)H(8n + 4) (n = 1-4) clusters. The energy density analysis (EDA) proposed by Nakai has been adopted to examine surface-molecule interactions for different cluster sizes. EDA results for the largest model cluster Si45H36 have shown that the adsorption-induced energy density variation in Si atoms decays with distance from the adsorption site.
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