A research team from the University of Waterloo has synthesized a prototype of a lithium-sulphur rechargeable battery that, thanks to its peculiar nanoscale structure, can store three times the power of a conventional lithium-ion battery in the same volume while being significantly lighter and potentially cheaper to manufacture.via Gizmag via Gizmodo
Successfully combining lithium and sulfur delivers much higher energy densities while reducing the cost of the materials used. According to internal testing, the composite material synthesized by Nazar's team can supply as much as 84 percent of the theoretical capacity of sulphur - three times the energy density of lithium transition cathodes. This should account for significantly more efficient batteries which will be lighter as well.
How much lighter? "We estimate the energy density of our cells to be about 1200 Wh/kg, for just the positive electrode, which would put the energy density of the cell at about 500 Wh/kg or more, but this depends on the other components of the cell," Dr. Nazar told us via email. "That is about a factor of 3 to 5 times more than a conventional lithium-ion battery. However, capacity fading can be more of an issue, along with lower volumetric energy and those need to be tackled more fully."
Finally, with regard to production costs, Dr. Nazar told us that, while the material themselves are certainly cheaper than those employed in lithium-ion batteries, it would be hard to quantify how much cheaper lithium-sulfur batteries will be. "Clearly the basic raw materials for the positive electrode (sulfur and carbon) are very inexpensive, but there are costs associated with processing, electrolyte, fabrication, etc that are highly dependent on the optimization of the materials and the battery configuration."