Gel-like coating can boost lithium-sulfur battery performance

Scientists have developed an ultra-thin gel-like coating material that has the potential to extend the life and improve the efficiency of lithium-sulfur batteries.

"Our approach is general, in that it can be integrated with virtually any kind of sulfur electrode to increase cycling stability," said lead investigator of the study Hailiang Wang, Assistant Professor of Chemistry at Yale University in New Haven, Connecticut, US.

In a study published online in the Proceedings of the National Academy of Sciences, the researchers described the new material which can be applied to any sulfur cathode.

A cathode is the positive terminal on a battery.

Sulfur cathodes coated with the material can be stably discharged and recharged for more than 1,000 cycles, enhancing the battery's efficiency and number of cycles, according to the researchers.

"The developed film is so thin and light it will not affect the overall size or weight of the battery, and thus it will function without compromising the energy and power density of the device," Wang said.

New types of electrodes -- positive and negative terminals -- are considered essential for the development of a new generation of high energy-density batteries.

As lithium-ion batteries -- currently widely used in mobile phones and laptops, among other electronic devices -- begin to reach their capacity limits, many researchers are looking at lithium-sulfur as a solution.

Sulfur is both lightweight and abundant, with a high theoretical energy capacity.

The Yale team made its discovery by combining the distinct properties of two material components.

They merged the mechanical strength of graphene oxide with the ability of a dendrimer molecule to confine lithium polysulfides.

The result is a gel-like slurry that can be readily coated as a 100-nanometer-thin film onto sulfur electrodes, the study said.

--IANS

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