Structural Design of Lithium-Sulfur Batteries: From Fundamental Research to Practical Application

Lithium-sulfur (Li-S) batteries have been considered as one of the most promising energy storage devices that have the potential to deliver energy densities that supersede that of state-of-the-art lithium ion batteries. Due to their high theoretical energy density and cost-effectiveness, Li-S batteries have received great attention and have made great progress in the last few years. However, the insurmountable gap between fundamental research and practical application is still a major stumbling block that has hindered the commercialization of Li-S batteries. This review provides insight from an engineering point of view to discuss the reasonable structural design and parameters for the application of Li-S batteries. Firstly, a systematic analysis of various parameters (sulfur loading, electrolyte/sulfur (E/S) ratio, discharge capacity, discharge voltage, Li excess percentage, sulfur content, etc.) that influence the gravimetric energy density, volumetric energy density and cost is investigated. Through comparing and analyzing the statistical information collected from recent Li-S publications to find the shortcomings of Li-S technology, we supply potential strategies aimed at addressing the major issues that are still needed to be overcome. Finally, potential future directions and prospects in the engineering of Li-S batteries are discussed.