Advances in lithium sulfur batteries pave the way for their commercial use

Lithium sulfur batteries have the potential to replace conventional lithium ion batteries one day. Because sulfur is inexpensive, non-toxic, and abundant in nature, it has garnered interest as a low-cost and environmentally-friendly energy storage option for wind and solar generated power. However, the technology still faces severe technical problems today, such as polysulfide dissolution and the shuttle effect, which prohibit the commercialization of such batteries.

Fang et al. present a comprehensive overview of recent developments in lithium sulfur battery efficiency. The review focuses on the latest advances of polysulfide mediation in batteries with liquid electrolytes, discussing new designs of cathode composition, the use of polysulfide barrier layers, and the selection of electrolyte components.

“This review is important as it summarizes recent developments of lithium-sulfur batteries that are feasible for large-scale industrial production,” said author Chen Fang.

Typically, lithium-sulfur batteries are made of lithium metal anodes, sulfur-based cathodes, and a separator, usually with a non-aqueous liquid electrolyte that contains lithium salts. Effective strategies for preventing the dissolution and shuttling of polysulfide species have been developed and demonstrated. For example, porous electrode composites, functional binders, interlayers and electrode coatings can help to reduce polysulfide dissolution at the cathode. Additional solutions include the use of co-solvents and electrolyte additives to avoid unwanted side reactions.

The authors conclude that further investigation of the complexity of sulfide chemistry is still needed to improve lithium-sulfur batteries, and future studies should focus on the electrochemistry processes and interactions between sulfides, solvents, and cathode materials.

Source: “Recent advances in polysulfide mediation of lithium-sulfur batteries via facile cathode and electrolyte modification,” by Chen Fang, Guangzhao Zhang, Jonathan Lau, and Gao Liu, APL Materials (2019). The article can be accessed at https://doi.org/10.1063/1.5110525 .