Australian researchers say they have developed the most powerful lithium-sulfur battery to date. The core is a particularly robust sulfur electrode, which a team headed by researcher Mahdokht Shaibani from Monash University in Clayton, Australia, is presenting in the science magazine “Science Advances”.
According to a message from the university, the rechargeable battery could outperform the current market leaders by more than four times.
First applications in aviation expected
Lithium-sulfur batteries are lighter and cheaper than the widespread lithium-ion batteries and can be manufactured inexpensively and in an environmentally friendly manner, such as the Fraunhofer Institute for Material and Beam Technology IWS in participating in the study Dresden explained.
The technology is very promising, but is still under development. “The first applications are seen where weight is an issue, for example in aviation,” said the head of the chemical surface and battery technology department at IWS, Holger Althues.
His team has been researching technology for years. Lithium-sulfur cells can store more energy than lithium-ion batteries with the same weight, but are larger.
So far, the material wears out too quickly
The raw materials are the decisive cost factor in industrial battery production, according to Althues. “In the lithium-sulfur cell, sulfur replaces the nickel-cobalt cathode of the conventional lithium-ion battery.” This opens up the potential for an inexpensive cell: Unlike nickel and cobalt, sulfur is a waste product and is available worldwide.
One problem with the lithium-sulfur battery has so far been the mechanical stability of the cathode expands and contracts noticeably during the operational absorption and release of lithium. This often causes micro-cracks and breaks in the material, causing the cell to wear out quickly.
The Australian research team has now developed and patented a promising solution to this problem. The sulfur is embedded in a specially designed layer of a binder and carbon, which can compensate for higher mechanical loads than previous cathodes and thus reduce the loss of performance and capacity.
Environmentally friendly process
The architecture of the layer was inspired by the production of detergents, explained the Monash University. The process enables stability that no other battery has ever had. “This approach not only favors high performance data and a long service life, but also simple and extremely cost-effective production using water-based processes,” said Monash researcher Matthew Hill.
“And it can lead to a significant reduction in environmentally hazardous waste.” This makes the new battery design attractive for future everyday applications.
“This work shows that a very good cathode can be produced using environmentally friendly processes,” said Althues, whose institute had built a prototype of the new cell. “This is a very important step, but there are further hurdles in the development of the components and cells until they are ready for the market, especially for use in electric vehicles.” (AP)