(Invited) New Electrode and Electrolyte Approaches for Rechargeable Li-S Battery

Abstract

A strong demand for low-cost and high-energy-density rechargeable batteries has spurred lithium-sulfur (Li-S) rechargeable battery research. First, sulfur is an abundant and low-cost material. Second, the Gibbs energy of the lithium (Li) and sulfur reaction is approximately 2,600 Wh/kg, assuming the complete reaction of Li with sulfur to form Li2S, more than five times the theoretical energy of transition metal oxide cathode materials and graphite coupling. With these advantages, Li-S batteries could be both high energy density and low cost, satisfying demand in energy storage for transportation application. The major obstacle is the loss of sulfur cathode material as a result of polysulfide dissolution into common electrolytes, which causes a shuttle effect and significant capacity fade. The polysulfide shuttle effect leads to poor sulfur utilization and fast-capacity fade, which have hindered widespread use of rechargeable Li-S batteries. Here, we present a body of work on both electrode materials design and synthesis, electrode fabrication and novel electrolyte materials for Li-S rechargeable batteries. We report the development of new electrode materials, electrolytes and additives for Li-S battery. The properties of the combined electrode and electrolyte stabilized polysulfides, and promoting the polysulfide affiliation with the electrode substrate to prevent polysulfide dissolution.