This dataset includes operando Near-Edge X-ray Absorption Fine Structure (NEXAFS) spectra of lithium organo-sulfur battery half-cells during Cyclic Voltammetry (CV), as well as ex-situ NEXAFS spectra of organo-sulfur compounds and polymer networks. All NEXAFS spectra were taken in fluorescence mode using energy-dispersive silicon drift detectors (SDD) in the PTB laboratory at BESSY II. The operando NEXAFS spectra of lithium organo-sulfur battery half-cells were taken at the Four Crystal Monochromator (FCM) beamline using Si (111) crystals with a fluorescence detection angle of 60 °. CV was performed with a BioLogic VSP potentiostat. The ex-situ NEXAFS spectra of organo-sulfur compounds and polymer networks were taken at the Tender X-ray MicroFocus (MiFo) beamline, operated in Double Crystal Monochromator (DCM) mode using Si (111) crystals with a fluorescence detection angle of 90 °. The file names include the measurement technique (CV or NEXAFS) followed by the sample name and, if applicable, further keywords like "powder" for powder samples or "operando" for operando measurements.