Challenges and Key Parameters of Lithium-Sulfur Batteries on Pouch Cell Level

Lithium-sulfur (Li-S) technology was identified as a promising candidate to overcome energy density limitations of common lithium-ion batteries given the world-wide abundance of sulfur as a low-cost alternative to state-of-the-art active materials, such as Ni and Co. Li-S cells have received tremendous recognition in recent years, both from a scientific and industrial perspective. However, only few data on adequate multilayer-pouch cell characterization are available so far, and transparent calculations on components require more consideration. Because of the gap of lab cell characterization and prototype cell development, misinterpretations and false expectations are frequently reported, mostly resulting from lithium and electrolyte excess. For the commercialization of the Li-S technology, rapid transfer of new concepts on the prototype cell level is essential. Furthermore, fundamental studies should concentrate on fundamental scientific questions related to the main bottlenecks of Li-S cells: understanding anode and electrolyte degradation phenomena and realistic evaluation of stabilizing interfaces.