SELECTED STRATEGIES FOR ADDRESSING THE OPERATIONAL ISSUES OF RECHARGEABLE LITHIUM-SULFUR BATTERIES

Abstract

The very high theoretical specific capacity of sulfur makes it has the potential to be a high capacity cathode material for the next generation lithium batteries. The insulating property of sulfur, and the propensity to form soluble lithium polysulfides during the transformation, are however formidable technical challenges. One of the most recent developments is the implementation of the Li-S batteries as redox flow batteries as an attempt to combine the high energy density of Li-S batteries with the scalability of redox flow batteries. This thesis is an effort to address the most salient operational issues in Li-S batteries in both static-cell and flow-cell formats, with several selected strategies. Specifically, separator modifications (a controlled interlayer coating for collaborative interfacial effects, enhanced Li+ conduction through the separator), Li anode protection, and the use of redox-targeting for charge transfer; are used to increase the capacity and the cycle life of rechargeable Li-S batteries.