Methods and Cost Estimation for the Synthesis of Nanosized Lithium Sulfide

Abstract

Lithium sulfide (Li2S) is an alternative cathode material for lithium-sulfur batteries. It can mitigate the volume expansion problem encountered by the sulfur cathode, in addition, as a fully lithium-inserted cathode, it can be paired with lithium-free anodes or be assembled into anode-free batteries. However, commercially available Li2S powder delivers poor electrochemical performances due to the significant potential barrier during the first charging process, and therefore developing inexpensive synthesis route for nanosized Li2S with small diameter and low charging overpotential becomes the key to the construction of practical Li2S cathode. Herein, the preparation methods for Li2S nanoparticles are summarized, including laboratory synthesis methods and potential large-scale preparation routes; traditional industrial synthesis methods for commercially available Li2S are also attached as references. In particular, the scalability of these methods is mentioned, and the costs of the resulted Li2S products are also estimated and compared with the currently used cathode materials for Li-ion batteries. In the end, the commercially worthwhile research pathways for Li2S synthesis as well as the perspective on the practical production of Li2S are discussed. Useful guidance for the selection of practical Li2S synthesis routes is also provided.