Mechanistic analysis of Lithium-Sulfur electrode using Density functional theory and Molecular Dynamics framework

DFT and ReaxFF-MD dataset characterizing the structural, electronic, and mechanical properties of the complete lithium polysulfide series (Li₂Sₓ, x = 1, 2, 4, 6, 8) and elemental S₈, relevant to capacity fade in Li-S batteries. Includes DFT-computed band gaps, Bader charges, elastic constants, and phonon dispersion, alongside ReaxFF MD stress-strain data showing a two-orders-of-magnitude stiffness collapse (52 GPa to ~1 GPa) across the discharge pathway. Provides quantitative benchmarks for understanding cathode mechanical degradation in Li-S battery systems. Keywords: Lithium-sulfur batteries; DFT; ReaxFF; Elastic constants; Mechanical stability; Polysulfides