text: The alkali metal polysulfides arise by treatment of a solution of sulfide, e.g. sodium sulfide, with elemental sulfur:
  In some cases, these anions have been obtained as organic salts, which are soluble in organic solvents.
  The energy released in the reaction of sodium and elemental sulfur is the basis of battery technology. The sodium–sulfur battery and the lithium–sulfur battery require high temperatures to maintain liquid polysulfide and -conductive membranes that are unreactive toward sodium, sulfur, and sodium sulfide.
  Polysulfides are ligands in coordination chemistry. Examples of transition metal polysulfido complexes include titanocene pentasulfide|, , and . Main group elements also form polysulfides.