International Science Team Intensifies Research on Lithium-Sulfur Batteries
A research team at the MEET Battery Research Center at the University of Münster has kicked off the international joint project "AReLiS-3" to pursue research on lithium-sulfur batteries. Its aim is to develop, investigate and optimize novel cell designs, materials, electrode coatings and electrolytes for sulfur-based battery systems. These innovations promise to reduce the rapid aging of battery cells and pave the way for a technological and industrial breakthrough. Building on the results of the previous projects, research is now intensifying the characterization of the electrode interphases. The interphases significantly influence battery cell performance, especially with regard to the negative ageing effects which predominantly occur there. The Federal Ministry of Education and Research (BMBF) has agreed to provide the German project partners with around 1.9 million euros to finance the two-and-half-year project run.
The research team will use analytical methods to further decipher the electrochemical processes within the cells. In addition to the sulfur-based cathodes, researchers will investigate conventional nickel-manganese-cobalt-based cathodes and compare them with each other. “In a further step towards application, we will upscale the most promising lithium-sulfur concepts under industrial aspects and cycle and investigate them in pouch cells,” explained project manager Dr Simon Wiemers-Meyer, deputy head of the research division “Analytics & Environment” at MEET Battery Research Center.
This new research venture is the result of an aging issue that many lithium-sulfur concepts have faced in the past, namely the formation of soluble polysulfides in the electrolyte at the cathode. This causes an irreversible deposition of sulfur species on the anode. After just a few charging and discharging cycles, the capacity of the lithium-sulfur battery can drop to a low level. Using solid instead of liquid electrolytes is one approach to prevent the polysulfide migration. To address this problem, researchers in the predecessor projects “AReLiS-1 and -2” investigated the reactions of the cathodes in liquid, solid and hybrid electrolytes. The use of pure polymer, solid and hybrid electrolytes, for example, offered enormous potential for long-term stable lithium-sulfur batteries. In addition to reducing polysulfide migration, these electrolytes enabled a higher active material utilization. Based on the deeper insights into the chemical processes, the team developed new materials for lithium-sulfur batteries, as well as new methods for their analysis.
The MEET research team will collaborate with scientists from the Helmholtz Institute Münster of Forschungszentrum Jülich, Technische Universität Dresden, Fraunhofer IWS Dresden, Waseda University (Japan), National Institute of Advanced Industrial Science and Technology AIST (Japan), Tohoku University (Japan) and Kyushu University (Japan). The project runs from November 2023 to March 2026.