Lithium-sulfur (Li-S) batteries are a popular Li-ion alternative because they have a high capacity (1672 mAhg1) and energy density (2500 Wh kg1) while being inexpensive, environmentally friendly, and lightweight [1–3]. During cycling, Li/S is hampered by the low conductivity of S and the solubility of intermediary polysulfide species. Se and mixed SexSy have been shown to offer an appealing new class of cathode materials with good electrochemical performance in both Li and Na ion processes [4]. These new Se and Li/SexSy electrodes can cycle at ambient temperature, unlike existing Li/S batteries, which can only operate at high temperatures. Room temperature cycling is possible using Li/SexSy electrodes. Empirical interatomic potentials of Li2S were generated and confirmed against existing experimental and predicted structure, elastic properties, and phonon spectra in order to analyse large systems and the impact of temperature effectively. Complex high-temperature changes including Li2S melting were also replicated, as predicted by molecular dynamics simulations.