Developments in Lithium-Sulfur Batteries

The Lithium-Sulfur (Li-S) battery can become the new standard bearer for another battery revolution in the next 15 years, due to its potential availability of distinctively high-energy density, which puts the Li-S chemistry in a league of its own. In Li-S cells, the porous sulfur composite cathode is coated onto a thin metallized substrate, such as aluminum on a polymeric film. It is generally thought that the soluble high oxidation state of lithium polysulfides as well as soluble sulfur, which are generated at the cathode, diffuse to the lithium anode where they react directly with the lithium via a parasitic reaction to recreate the low oxidation state lithium polysulfides. Graphene shows a very high conductivity and large surface area, which is easily functionalized into hydrophilic or hydrophobic structure. The electrostatic interactions are enabled between the surfaces and polysulfides of metal oxides due to their hydrophilicity.