Creating Vacancy Strong Interaction to Enable Homogeneous High-Throughput Ion Transport for Efficient Solid-State...

Area of Science:

• Materials Science
• Electrochemistry
• Polymer Science

Background:

• Solid polymer electrolytes are crucial for safe, scalable solid-state lithium metal batteries.
• Key challenges include poor ionic conductivity and lithium dendrite growth, hindering battery performance.
• Existing electrolytes struggle with ion transport and interfacial stability.

Purpose of the Study:

• To develop a high-throughput lithium-ion transport pathway in composite polymer electrolytes.
• To address limitations in ionic conductivity and dendrite formation in solid-state batteries.
• To enhance the safety and cycle life of lithium metal batteries.

Main Methods:

• Incorporation of tungsten sulfide with sulfur vacancies into poly(vinylidene fluoride-co-hexafluoropropylene) based composite polymer electrolytes.
• Investigating the interaction of sulfur vacancies with polymer chains and lithium salts.
• Analyzing the effect of sulfur vacancies on anion behavior and lithium deposition.

Main Results:

• Achieved high ionic conductivity of 1.9 × 10^-3 S cm^-1 at 25 °C.
• Demonstrated suppressed lithium dendrite growth and uniform lithium deposition.
• Enabled an ultra-long cycle life exceeding 5500 hours in Li||Li symmetric cells.
• Attained a pouch cell capacity of 0.524 Ah with a sulfurized polyacrylonitrile cathode.

Conclusions:

• The developed composite polymer electrolyte with sulfur vacancies provides a homogeneous, high-throughput Li-ion transport mechanism.
• This approach effectively enhances ionic conductivity and suppresses dendrite growth, crucial for solid-state lithium metal batteries.
• The strategy offers a promising pathway for developing next-generation high-performance and safe energy storage devices.