Unlocking Li‒S chemistry via acoustic-induced entropy-driven electrolyte

Area of Science:

• Materials Science
• Electrochemistry
• Energy Storage

Background:

• Lithium-sulfur (Li-S) batteries present a promising alternative to current energy storage technologies due to their high theoretical energy density.
• However, practical application is hindered by issues such as polysulfide shuttling and lithium dendrite formation.
• Existing electrolyte engineering strategies often involve static or invasive modifications.

Purpose of the Study:

• To develop a novel electrolyte design for Li-S batteries that addresses polysulfide shuttling and lithium dendrite formation.
• To enhance sulfur conversion kinetics and maintain a stable lithium working interface.
• To demonstrate a high-performance Li-S battery using the new electrolyte formulation.

Main Methods:

• An acoustic-induced entropy-driven electrolyte was designed and implemented.
• A comprehensive suite of instrumental and computational tools was employed for analysis.
• The electrolyte's effect on sulfur and lithium species nucleation and Li-ion desolvation was investigated.

Main Results:

• The entropy-driven electrolyte promoted homogeneous nucleation of sulfur and lithium species.
• The electrolyte dictated a favorable Li-ion desolvation process.
• A lean dosage (2.9 µL mg⁻¹) enabled a 1.1 Ah pouch cell with 404.1 Wh kg⁻¹ specific energy without packaging.

Conclusions:

• The acoustic-induced entropy-driven electrolyte effectively steers Li-S chemistry.
• This approach provides a viable solution for overcoming critical challenges in Li-S battery technology.
• External field modulation offers a new paradigm for designing high-performance energy storage devices.