High-Performance Metal-Organic Framework-Based Single Ion Conducting Solid-State Electrolytes for Low-Temperature...

Area of Science:

• Materials Science
• Electrochemistry
• Energy Storage

Background:

• Single-ionic conducting electrolytes are crucial for developing safer, high-energy-density lithium metal batteries.
• Existing electrolytes often face challenges with dendrite formation and limited operational temperature ranges.

Purpose of the Study:

• To design and synthesize a novel single-ionic conducting solid-state electrolyte (SSE) based on metal-organic frameworks (MOFs).
• To evaluate the electrochemical performance and lithium dendrite suppression capabilities of the developed MOF-based SSE.

Main Methods:

• Post-synthetic modification of UiO-66-NH2 metal-organic framework using trifluoromethanesulfonyl groups.
• Characterization of ionic conductivity, activation energy, electrochemical window, and Li+ transference number.
• Assembly and testing of solid-state lithium metal batteries with LiFePO4 cathodes.

Main Results:

• Achieved high ionic conductivity (2.07 × 10-4 S cm-1 at 25 °C) and a high Li+ transference number (0.84).
• Demonstrated a wide electrochemical window (up to 4.52 V) and effective suppression of lithium dendrite growth.
• Exhibited excellent rate performance and cyclic stability in solid-state batteries, including low-temperature operation at 0 °C.

Conclusions:

• The MOF-based SSE offers a promising pathway for advanced lithium metal batteries.
• The developed electrolyte demonstrates superior performance, safety, and stability for all-solid-state battery applications.