Looking to improve performance and reduce the risks of overheating, South Korean researchers at Pohang University have created a lithium-ion battery made from a porous solid.Looking to improve performance and reduce the risks of overheating, South Korean researchers at Pohang University have created a lithium-ion battery made from a porous solid.
The new battery is built from pumpkin shaped molecules called cucurbit[6]uril – or CB[6]. These molecules are organised in a honeycomb like structure. The molecules have 1D channels running through them, measuring 7.5Å on average. The physical structure of the porous CB[6] enables the lithium ions to battery to diffuse more freely than in conventional lithium ion batteries and to exist without the separators found in other batteries.
In tests, the CB[6] solid electrolytes were said to show impressive lithium ion conductivity. To compare this to existing battery electrolytes, the team measured the lithium transference number, which was recorded at 0.7 to 0.8 compared to the figure of 0.2 to 0.5 of existing electrolytes. The team also cycled the batteries at temperatures between 25 and 100°C for four days. The cells were said to show no thermal runaway and hardly any change in conductivity.
The CB[6] framework is said to accommodate various conventional liquid electrolytes and to potentially enable lithium air batteries.
Author
Graham Pitcher
Source: www.newelectronics.co.uk