Scientists from Singapore-based NanoBio Lab (NBL) have developed a means of making lithium-sulfur cathodes that increase specific energy and curbs capacity fade.
The team began by building the carbon host before adding the sulfur source to obtain a 3D interconnected porous nanomaterial.
The team reports its cathode has a 48% higher specific energy and 26% less capacity fade than conventionally prepared sulfur cathodes, and when more sulfur is added to the material, its cathode can achieve a practical area capacity of 4mAh/cm2
NBL says their cathode demonstrated specific capacity of up to 1,220mAh/g. A typical lithium-ion cathode is from around 140mAh/g.
The researchers also claim their cathode can maintain its high capacity over 200 charging cycles with minimal loss in performance, a feat lithium-sulfur researchers have previously been unable to sustain during repeated cycling.
Professor Jackie Ying, who leads the NBL research team, said: “We have shown that the preparation technique of sulfur cathodes has a strong influence on the electrochemical performance in lithium-sulfur batteries.
“Our method is industrially scalable and we anticipate that it would have a significant impact on the future design of practical lithium-sulfur batteries.”
As well as cathodes, the NBL researchers are working on designing and optimising the lithium-sulfur anode, separator and electrolyte through nanomaterials engineering.
The goal is to develop a full cell system for lithium-sulfur batteries that have better energy storage capacity than conventional lithium-ion batteries.
In the UK, Oxis Energy plans to build a manufacturing plant in Wales for the production of electrolyte and cathode active material specifically for the mass production of lithium-sulfur cells.
Last month it began collaborating with Bye Aerospace in the US to produce a lithium-sulfur battery cell to be considered for its future electric aircraft.
Image (from left) The NBL research team: Dr. Ayman AbdelHamid, Jian Liang Cheong and professor Jackie Y. Ying.