“This is a major step forward and brings the lithim-sulphur battery one step closer to reality,” said Nazar, who also holds the Canada Research Chair in Solid State Energy Materials and was named a Highly Cited Researcher by Thomson Reuters.
Nazar’s group is best known for their 2009 Nature Materials paper demonstrating the feasibility of a Li-S battery using nanomaterials. In theory, sulphur can provide a competitive cathode material to lithium cobalt oxide in current lithium-ion cells. Sulphur as a battery material is extremely abundant, relatively light, and very cheap.
Unfortunately, the sulphur cathode exhausts itself after only a few cycles because the sulphur dissolves into the electrolyte solution as it’s reduced by incoming electrons to form polysulphides.
Nazar’s group originally thought that porous carbons or graphenes could stabilize the polysulphides by physically trapping them. But in an unexpected twist, they discovered metal oxides could be the key. Their initial work on a metallic titanium oxide was published earlier in August in Nature Communications.