Latest material concepts for mobile energy storage

Press release (Nr. XIX) - Fraunhofer IWS Dresden / September 26, 2013

Many research organizations and enterprises focus their activities on research in the field of renewable energies. The Fraunhofer IWS will present the latest results in the workshop “Lithium-Sulfur Batteries” on November 6 - 7, 2013. Renowned national and international experts from industry and science will come together to gain profound insight in the current and future trends and developments.

Coating system for electrodes in a roll-to-roll procedure at the Fraunhofer IWS
© Jürgen Jeibmann / Fraunhofer IWS Dresden
Coating system for electrodes in a roll-to-roll procedure at the Fraunhofer IWS

Holger Althues, coordinator of the IWS Battery Center and project manager of several related research projects presents the latest results of current research findings: “To my mind lithium-sulfur batteries are the most promising innovation for future energy storage devices.” They have two to four times more specific energy than conventional lithium-ion batteries. “A further advantage is that sulfur is an abundant, non-toxic and inexpensive material in contrast to cobalt-based cathode materials.

The major challenge, however, is to improve the lifespan of lithium-sulfur batteries. Novel materials, such as nano-structured carbon-sulfur composites, solid-state electrolytes and silicon-alloy anodes promise a drastic increase of stability. Recently, IWS scientists succeeded in developing lithium-sulfur cells, which demonstrate with their more than 1300 charge/discharge cycles an excellent efficiency of nearly 100 %. The significantly improved cell stability can be clearly attributed to the novel material composition. The IWS scientists combined carbon-silicon composite cathodes with porous carbon-sulfur cathodes. Due to high sulfur utilization these nano-composite cathodes allow for a specific capacity of more than 1400 Ah kg-1 (related to the mass of sulfur).