Ultrathin composite polymer electrolyte with ordered ion pathways for all-solid-state lithium-metal batteries

Area of Science:

• Materials Science
• Electrochemistry
• Energy Storage

Background:

• High-energy-density all-solid-state lithium-metal batteries (ASSLMBs) require thin, robust solid-state electrolytes (SSEs) with efficient lithium-ion (Li+) transport.
• Current SSEs often face challenges in mechanical strength, scalability, and interfacial stability with lithium metal anodes.

Purpose of the Study:

• To develop an ultrathin (10 μm) SSE with ordered ion pathways for scalable ASSLMB production.
• To enhance Li+ transport, mechanical properties, and interfacial stability for improved battery performance and safety.

Main Methods:

• Fabrication of an SSE supported by a poly(ether sulfone) scaffold with vertically aligned microchannels.
• Characterization of ionic conductivity, Li+ transference number, and electrochemical performance in ASSLMBs.
• Evaluation of dendrite suppression capability and cycling stability at various temperatures.

Main Results:

• The SSE exhibits ordered ion pathways, low tortuosity, and efficient Li+ transport.
• Achieved room temperature ionic conductivity of 0.10 mS cm−1 and Li+ transference number of 0.51.
• Demonstrated excellent cycling stability (81% retention after 300 cycles at 1C/60°C) and safe operation up to 100°C.

Conclusions:

• The scaffold-supported SSE offers a promising strategy for scalable ASSLMBs with enhanced safety and performance.
• The ultrathin SSE design facilitates uniform Li deposition and superior dendrite suppression.
• The developed electrolyte demonstrates versatility across different cathode chemistries.