1. Shenyang National Laboratory for Materials Science, Institute of Metal Research, Chinese Academy of Sciences, Shenyang 110016, China;2. School of Materials Science and Engineering, University of Science and Technology of China, Shenyang 110016, China
Abstract:
Lithium-sulfur batteries are one of the prospective next-generation power sources that can replace commercial lithium-ion batteries owing to their high theoretical energy density, eco-friendliness, and low cost. However, the insulating nature of the charge–discharge products, the shuttle effect of soluble lithium polysulfides, the volume expansion of the sulfur cathode, and the uncontrollable growth of lithium dendrites severely affect the actual capacity and cycling stability of lithium-sulfur batteries. Replacing the inorganic sulfur (S8) cathode with an organosulfur-based cathode is a promising strategy for resolving the aforementioned issues. By modulating the fundamental units of the organosulfur compound, including the sulfur chain, carbon chain, and their interactions, the electrochemical reaction process can be altered, the ion/electron conductivity can be increased, and the shuttle effect can be effectively suppressed. In addition, organosulfur compounds as electrolyte additives can regulate the reaction process of the sulfur cathode and protect the lithium anode by forming a stable solid electrolyte interface, and as polymer electrolyte segments, they can accelerate the conduction of lithium ions. This review provides a detailed outline of the research progress and application of organosulfur compounds as cathodes, electrolyte additives, and solid-state electrolytes in lithium-sulfur batteries. The structure, reaction mechanism, and electrochemical properties of organosulfur compounds are correlated to provide comprehensive insights that can help address the prevailing issues of lithium-sulfur batteries. Finally, future prospects, including the challenges and potential solutions, are presented to guide the design, synthesis, and mechanistic studies of high-performance organosulfur compounds to realize a practical lithium-sulfur battery.
