Toward robust solid-state lithium metal batteries by stabilizing a polyethylene oxide-based solid electrolyte...

Area of Science:

• Materials Science
• Electrochemistry
• Polymer Science

Background:

• All-solid-state lithium batteries require high-performance solid-state electrolytes (SSEs) for high energy density.
• Developing lightweight, ultrathin SSEs with high Li+ conductivity remains a significant challenge.

Purpose of the Study:

• To design a mechanically flexible and robust SSE using bacterial cellulose (BC) as a 3D backbone.
• To investigate the electrochemical properties and performance of the BC-PEO/LiTFSI SSE in lithium-based batteries.

Main Methods:

• Fabrication of a novel SSE (BC-PEO/LiTFSI) utilizing bacterial cellulose as a rigid support.
• Integration and polymerization of BC and PEO/LiTFSI via intermolecular hydrogen bonding.
• Electrochemical testing of Li-Li symmetric cells and Li-LiFePO4 and Li-S full cells.

Main Results:

• The BC-PEO/LiTFSI SSE demonstrated excellent electrochemical cycling stability over 1000 hours in Li-Li symmetric cells.
• Li-LiFePO4 full cells exhibited steady cycling performance.
• Li-S full cells maintained high capacity (610 mAh g-1) for over 300 cycles at elevated temperature.

Conclusions:

• Bacterial cellulose serves as an effective 3D backbone for developing flexible and conductive SSEs.
• The BC-PEO/LiTFSI electrolyte shows great promise for high-performance all-solid-state lithium batteries.
• This approach offers an environmentally friendly and low-cost route for advanced energy storage materials.