Chinese researchers explain the loss of sulphur in lithium-sulphur batteries using electron microscopy in a Nature paper. Materials chemistry professor Moniek Tromp is critical.

Lithium-sulfur batteries could be the next generation of lithium-ion batteries. In theory, they can store a lot of energy. Sulphur atoms form S₈ and can therefore transfer 16 electrons per molecule; two electrons per S. Moreover, sulphur is a waste product from the petrochemical industry, so it is widely available and cheap, although it has to be purified before it can be used in a battery. Despite their high energy density and relatively low cost, lithium-sulphur batteries have not yet been realised on a large scale. One of the problems is the high solubility of sulphur, which can precipitate with lithium as lithium sulphide on the lithium anode, deactivating the battery.