An Ultra-Long-Life Flexible Lithium-Sulfur Battery with Lithium Cloth Anode and Polysulfone-Functionalized Separator

Area of Science:

• Materials Science
• Electrochemistry
• Energy Storage

Background:

• Flexible and high-performance batteries are crucial for the advancement of wearable electronics.
• Lithium-sulfur batteries offer high energy density, making them suitable for flexible power sources.

Purpose of the Study:

• To develop flexible lithium-sulfur full cells with enhanced stability and electrochemical performance.
• To address challenges like polysulfide shuttle and lithium dendrite formation in flexible batteries.

Main Methods:

• Fabrication of flexible lithium-sulfur cells using ultrastable lithium cloth anodes, polysulfone-functionalized separators, and sulfur/graphene/boron nitride nanosheet cathodes.
• Decoration of carbon cloth anodes with lithiophilic 3D MnO2 nanosheets to enhance flexibility and limit dendrite growth.
• Functionalization of commercial separators with polysulfone (PSU) via phase inversion for improved thermal stability and reduced pore size.

Main Results:

• The developed flexible lithium-sulfur cells demonstrated excellent mechanical flexibility and electrochemical performance.
• A superlong cycle life of 800 cycles was achieved in the folded state.
• A high areal capacity of 5.13 mAh cm-2 was obtained, attributed to inhibited polysulfide shuttle and dendrite formation.

Conclusions:

• The flexible battery strategy presented is a versatile and scalable platform for developing high-performance flexible batteries.
• The synergistic effects of modified anodes, functionalized separators, and cathode interlayers effectively control key degradation mechanisms.
• This work paves the way for advanced flexible power sources for next-generation electronics.