Will Sulfide Electrolytes be Suitable Candidates for Constructing a Stable Solid/Liquid Electrolyte Interface?

Area of Science:

• Electrochemistry
• Materials Science
• Energy Storage

Background:

• Conversion-type batteries offer high capacity but suffer from poor stability due to the shuttle effect.
• Solid-electrolyte separators can prevent mass exchange and mitigate the shuttle effect.
• Achieving a stable interface between solid and liquid electrolytes is crucial for battery performance.

Purpose of the Study:

• To investigate the interfacial stability between sulfide solid electrolytes and liquid electrolytes.
• To develop a stable solid-electrolyte separator for hybrid lithium-sulfur batteries.
• To improve the performance and stability of lithium-sulfur batteries.

Main Methods:

• Formation of a protective layer of ether-solvated Li3PS4 at the sulfide/liquid electrolyte interface.
• Design of a composite separator using β-Li3PS4-coated Li7P3S11.
• Testing of hybrid lithium-sulfur batteries with the composite separator.

Main Results:

• A stable interface with low resistance and limited side reactions was formed between β-Li3PS4 and ether-based liquid electrolytes.
• The β-Li3PS4-coated Li7P3S11 separator demonstrated high ion conductivity and interfacial stability.
• Hybrid Li-S batteries achieved a high discharge capacity of 1047 mA h g-1 and a 2.06 V plateau after 150 cycles.

Conclusions:

• The formation of an ether-solvated Li3PS4 protective layer is key to achieving stable interfaces.
• The developed composite separator enables high-performance hybrid lithium-sulfur batteries.
• This approach effectively addresses the shuttle effect, enhancing battery longevity and capacity.