Lithium metal anodes are indispensable for next-generation batteries including Lithium-Sulfur and Lithium-air batteries which show high promise for electric vehicles and other energy storage applications. Challenges such as extreme reactivity and lithium dendrite formation have kept lithium metal anodes away from practical applications. Lithium dendrite formation on anode surfaces during the charging process originates from the inhomogeneous deposition of metallic lithium during the electrochemical reduction of lithium cations. However, the underlying mechanisms of Li ion deposition from the electrolyte solution onto the anode surface are still poorly understood due to its inherent complexity. In this work, Density Functional Theory (DFT) simulations and thermodynamic integration calculations are conducted to study the electron and ion transfer between lithium metal slab and the electrolyte in absence of an external field. The slow growth approach allow the energy barriers on the diffusion and deposition pathway to be studied. This method illuminate the underlying mechanisms on lithium-ion deposition and provide a better understanding of the early stages of dendrite nucleation. We explore the effect of the solvent chemistry and structure, distance of the solvated complex from the surface, anion-cation separation, and concentration of Li-salts on the deposition of lithium ions from the electrolyte phase onto the surface. It is found that the structure and properties of the solvation shell around the lithium cation has a great influence on the ability of the cation to diffuse as well as on its surrounding electron environment.
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