Developing advanced separators with tailored properties for lithium-sulfur (Li-S) batteries
Tor Olav Sunde
SINTEF Industry, dept. Sustainable Energy Technology
Li-S batteries have great potential, with a theoretical energy density five times higher than lithium-ion batteries, while also using inexpensive and more abundant materials. However, challenges, in particular the migration of lithium polysulfides (LPS) through the separator, must be addressed to improve the performance and lifetime of Li-S batteries. In this work, we developed separators with tailored functionalities to address such issues. This includes developing MOFs with desired pore structures to provide selective channels that inhibit LPS migration and ensure homogeneous transport of Li-ions. MOF’s active sites also facilitate the conversion of the LPS. Different methods were used to incorporate MOFs into the separator, such as coating onto commercial separators and electrospinning into hybrid polymer fibre-MOF structures. We demonstrate promising results, including long cycle life (>1000 cycles), high initial capacity and good rate capabilities.
