The dissolution and diffusion of intermediate lithium polysulfide species forming during operation of Li-S batteries can lead to the loss of active material and reduced capacity over time. The characterization of those species and inhibition of their formation can result in improved Li-S batteries. Here, for the first time, we present a facile HPLC-ICP-MS method for the speciation of polysulfide anions in Li₂S_n mixtures in organic solvents [1]. The optimized procedure has an advantage of not using additional O₂ gas and not cooling spray chamber while introducing organic eluents to the plasma, with chromatography signal-to-noise ratio being on a high level. Using the method for the model solutions Li₂S_n (n = 4−8), S₄²⁻ was found to be the most abundant species. Additionally, the technique was used to investigate the influence of electrolyte additives of different nature used in Li-S batteries and in “anode-free” lithium-sulfide batteries. 

[1] A. Sadykov, et al. J. Anal. At. Spectrom., 2024, 39, 2480-2487.