Revisiting Scientific Issues for Industrial Applications of Lithium–Sulfur Batteries

Abstract

Inspired by high theoretical energy density (~2600 W h kg−1) and cost-effectiveness of sulfur cathode, lithium–sulfur batteries are receiving great attention and considered as one of the most promising next-generation high-energy-density batteries. However, over the past decades, the energy density and reliable safety levels as well as the commercial progress of lithium–sulfur batteries are still far from satisfactory due to the disconnection and huge gap between fundamental research and practical application. Therefore, it is highly necessary to revisit the scientific issues for the industrial applications of lithium–sulfur batteries. In this review, we focus on discussing the impact of design parameters (such as compaction density, sulfur loading, and electrolyte/sulfur ratio) on the electrochemical performance of lithium–sulfur batteries and corresponding inherent relationship and rules between them. We also propose the practical design rules of advanced sulfur electrodes. Moreover, safety hazard in respect of electrolyte, separator, and lithium metal anode is also illustrated in detail. With the target of paving the way for practical application of lithium–sulfur batteries, feasible solutions and strategies are brought up to address the aforementioned problems. Finally, we will discuss the current challenges and future research chance of lithium–sulfur batteries.