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To explore the potential of molecular gas treatment of freshly cut lithium foils in non-electrolyte based passivation of high energy-density Li anodes, density functional theory (DFT) has been used to study the decomposition of molecular gases on metallic lithium surfaces. By combining DFT geometry optimization and Molecular Dynamics, the effects of atmospheric (N2, O2, CO2) and hazardous (F2, SO2) gas decomposition on Li(bcc) (100), (110), and (111) surfaces on relative surface energies, work functions, and emerging electronic and elastic properties are investigated. The simulations suggest that exposure to different molecular gases can be used to induce and control reconstructions of the metal Li surface and substantial changes (up to over 1 eV) in the work function of the passivated system. Contrary to the other considered gases, which form metallic adlayers, SO2 treatment emerges as the most effective in creating an insulating passivation layer for dosages <= 1 mono-layer. The substantial Li->adsorbate charge transfer and adlayer relaxation produce marked elastic stiffening of the interface, with the smallest change shown by nitrogen-treated adlayers.

In this paper we have investigated via experimental and simulations techniques the transport properties, in terms of total ionic conductivity and ion diffusion coefficients, of ionic liquids and lithium salt mixtures composed of two anions, bis(fluorosulfonyl)imide (FSI) and bis(trifluoromethanesulfonyl)imide (TFSI), and two cations, N-ethyl-N-methylimidazolium (emim) and lithium. The comparison of the experimental results with the simulations shows an exceptional agreement over a wide temperature range. Of particular interest is the high agreement achieved at lower temperature, which is a result of the extended simulation length of, at least, a factor of 5 compared with previous work. The results show as the addition of TFSI favor the formation of lithium dimers (Li+ - TFSI- - Li+). A closer analysis of such dimers shows that involved lithium ions move nearly as fast as single lithium ions although they have a different coordination and much slower TFSI exchange rates., Comment: 21 pages, 9 figures; JPC submitted

This paper has been withdrawn by the author since it had been submitted to Journal of Physical Chemistry C., Comment: This paper has been withdrawn