Lithium-sulfur: cycle-resistant, intrinsically safe battery cells with energy densities > 400 Wh/kg

Press release (Nr. IX) - Fraunhofer IWS Dresden, /

Lithium-sulfur batteries carry great potential for the rather slowly developing electro mobility market. In the future, specific energy densities of more than 600 Wh/kg are expected, a density which, compared to that of lithium-ion cells (max. 250 Wh/kg), makes a decisive increase to the range of electric cars.

Schematische Darstellung der Entwicklungsziele in LiScell mit intrinsisch sicheren, einfach zu verarbeitenden Elektroden-materialien; erste Zellen können als Pilot-Batteriemodul in einer autonomen Fluganwendung zum Einsatz kommen
© Fraunhofer IVI Dresden
Schematische Darstellung der Entwicklungsziele in LiScell mit intrinsisch sicheren, einfach zu verarbeitenden Elektroden-materialien; erste Zellen können als Pilot-Batteriemodul in einer autonomen Fluganwendung zum Einsatz kommen

In addition, the expensive cathode material of traditional lithium-ion cells is substituted by sulfur, which is less expensive, non-toxic and available in virtually unlimited quantities. Nevertheless considerable challenges remain with respect to the concept realization of high energy cells with sufficient cycle stabilities.

For the last five years Fraunhofer IWS scientists have been researching the development of suitable electrode materials and the fabrication procedures for a cost-efficient high energy cell, based on the lithium-sulfur technology.

Due to improved electrode materials prototype cells were developed, which, apart from a high capacity, have more than 4.000 reversible charge/discharge cycles.

Within the framework of the strategic in-house research project "LiCell" four Fraunhofer institutes, under the direction of the IWS, have started working on further topics concerning fabrication procedures, material development, scalable production procedures for anodes and cathodes as roll material, cell setup as well as modules including battery management systems.

Recent developments around the topic of lithium-sulfur batteries will be presented and discussed by international experts from industry and science at the "Lithium-Sulfur Workshop" in Dresden, November 12 – 13, 2014.