A Novel Super-Toughness and Self-Healing Solid Polymer Electrolyte for Solid Sodium Metal Batteries

Area of Science:

• Materials Science
• Electrochemistry
• Energy Storage

Background:

• Solid sodium metal batteries (SSMBs) are promising for high energy density and safety.
• Sodium dendrite growth and poor electrolyte properties hinder SSMB application.

Purpose of the Study:

• To develop a composite polymer electrolyte (CPE) with liquid metal (LM) nanoparticles for SSMBs.
• To investigate the effect of LM on dendrite inhibition and battery performance.

Main Methods:

• Designed a polyethylene oxide-based CPE incorporating LM nanoparticles.
• Studied LM nanoparticle movement under electric fields within the solid electrolyte.
• Fabricated and tested symmetric SSMB cells and pouch batteries.

Main Results:

• LM nanoparticles facilitated sodium return to the anode and alloyed with dendrites, inhibiting growth.
• Symmetric cells demonstrated cyclic stability over 1800 and 800 hours at 0.1 and 0.2 mA cm⁻², respectively.
• Pouch batteries achieved an energy density of 230 Wh kg⁻¹.

Conclusions:

• LM nanoparticles are effective performance-enhancing fillers for CPEs in SSMBs.
• This approach shows significant potential for developing high-performance SSMBs.
• LM integration offers a viable strategy for overcoming dendrite issues in solid-state batteries.