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Abstract Metal‐sulfur batteries are a promising next‐generation energy storage technology, offering high theoretical energy densities with low cost and good sustainability. An active area of research is the development of electrolytes that address unwanted migration of sulfur and intermediate species known as polysulfides during operation of metal‐sulfur batteries, a phenomenon that leads to low energy efficiency and short life‐spans. A particular class of electrolytes, gel polymer electrolytes, are especially attractive for their ability to repel polysulfides on the basis of structure, electrostatics, and other polymer properties. Herein, within the context of magnesium‐ and lithium‐sulfur batteries, we investigate the impact of gel polymer electrolyte cation solvation capacity, a property related to network dielectric constant and chemistry, on sulfur/polysulfide‐polymer interactions, an understudied property‐performance relationship. Polymers with lower cation solvation capacity are found to permanently absorb less polysulfide active material, which increases sulfur utilization for Li−S batteries and significantly increases charge efficiency and life‐span for Li−S and Mg−S batteries.
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Recent Progress of Anode Protection in Li–S Batteries
Lithium‐ion batteries have gradually reached their theoretical limits. To meet the growing demand for higher energy storage technology, finding alternative battery chemistries has become the major concern. Fortunately, lithium–sulfur batteries are considered the most promising next‐generation energy storage technology due to being cost‐effective and having high theoretical energy density. However, the further commercialization of lithium–sulfur batteries is hindered due to the growth of lithium dendrites and the shuttle effect of soluble lithium polysulfides. This review provides an overview of the challenges facing lithium–sulfur batteries. Furthermore, a comprehensive overview of lithium metal protection strategies is provided including electrolyte optimization, construction of artificial solid electrolyte layers, utilization of hosting materials, and design of separators, as well as a theoretical understanding and analysis of the underlying methods. This review puts forward general conclusions and prospects for the practical application of lithium–sulfur batteries in the future and the promotion of technology development of lithium metal batteries.
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- Award ID(s):
- 2119688
- PAR ID:
- 10390034
- Publisher / Repository:
- Wiley Blackwell (John Wiley & Sons)
- Date Published:
- Journal Name:
- Energy Technology
- Volume:
- 11
- Issue:
- 1
- ISSN:
- 2194-4288
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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