Room-Temperature Performance of Poly(Ethylene Ether Carbonate)-Based Solid Polymer Electrolytes for All-Solid-State...

Area of Science:

• Materials Science
• Electrochemistry
• Polymer Chemistry

Background:

• Poly(ethylene oxide) (PEO)-based solid polymer electrolytes often suffer from low ionic conductivity at reduced temperatures.
• Developing solid polymer electrolytes that operate efficiently at room temperature is crucial for advanced lithium battery applications.

Purpose of the Study:

• To synthesize and characterize a novel amorphous poly(ethylene ether carbonate) (PEEC) solid polymer electrolyte.
• To evaluate the performance of PEEC-based electrolytes in solid-state lithium batteries, focusing on ionic conductivity, electrochemical stability, and lithium transference number.
• To assess the potential of a cross-linked PEEC electrolyte in a practical all-solid-state lithium battery cell.

Main Methods:

• Synthesis of amorphous poly(ethylene ether carbonate) (PEEC) via ring-opening polymerization of ethylene carbonate.
• Preparation of a cross-linked solid polymer electrolyte using PEEC and tetraethyleneglycol diacrylate via photo cross-linking.
• Assembly and testing of a solid-state Li/LiNi0.6Co0.2Mn0.2O2 cell using the cross-linked PEEC electrolyte.

Main Results:

• The synthesized PEEC exhibited improved ionic conductivity, electrochemical stability, and lithium transference number compared to PEO.
• A flexible thin film of cross-linked PEEC solid polymer electrolyte was successfully fabricated.
• The solid-state Li/LiNi0.6Co0.2Mn0.2O2 cell demonstrated a high initial discharge capacity of 141.4 mAh g-1 with good capacity retention at room temperature.

Conclusions:

• Amorphous PEEC is a promising material for solid polymer electrolytes, overcoming low-temperature conductivity issues.
• Cross-linked PEEC-based solid polymer electrolytes are suitable for high-performance, room-temperature operating all-solid-state lithium batteries.
• The developed electrolyte shows significant potential for next-generation ambient-temperature lithium battery technologies.