Multisite Crosslinked Poly(ether-urethane)-Based Polymer Electrolytes for High-Voltage Solid-State Lithium Metal...

Area of Science:

• Materials Science
• Electrochemistry
• Polymer Chemistry

Background:

• Solid-state polymer electrolytes (SPEs) are crucial for high-energy-density and safe high-voltage lithium-metal batteries.
• Existing SPEs suffer from poor mechanical strength, low ionic conductivity, and unstable high-voltage interfaces.
• Overcoming these limitations is key to realizing the full potential of next-generation batteries.

Purpose of the Study:

• To develop a novel crosslinked poly(ether-urethane)-based SPE with enhanced properties for high-voltage lithium-metal batteries.
• To improve Li+ transport, mechanical stability, and interfacial compatibility.
• To demonstrate the practical applicability of the developed SPE in high-energy-density battery systems.

Main Methods:

• Fabrication of a crosslinked poly(ether-urethane)-based SPE using amino-modified Zr-porphyrin-based metal-organic frameworks (ZrMOF) as cross-linking nodes.
• Characterization of the SPE's ionic conductivity, mechanical strength, and electrochemical stability.
• Testing of Li||Li symmetric cells and LiNi0.8Co0.1Mn0.1O2||Li cells to evaluate cycle life and performance.

Main Results:

• Achieved high Li+ conductivity (5.7 × 10-4 S cm-1 at 30°C) and a high Li+ transference number (0.84).
• Demonstrated robust mechanical strength with a record cycle life of 8000 hours in Li||Li symmetric cells.
• Enabled a high discharge capacity (182 mAh g-1 at 0.3 C over 500 cycles) and a high energy density of 446 Wh kg-1 in a 1.5-Ah pouch cell.

Conclusions:

• The novel crosslinked SPE exhibits superior ionic conductivity, mechanical robustness, and electrochemical stability.
• The incorporation of ZrMOF effectively enhances Li+ transport and structural integrity.
• The developed SPE shows significant promise for practical application in high-voltage solid-state lithium-metal batteries.