A fire-retarding electrolyte using triethyl phosphate as a solvent for sodium-ion batteries

Area of Science:

• Electrochemistry
• Materials Science
• Energy Storage

Background:

• Sodium-ion batteries (SIBs) are a promising alternative to lithium-ion batteries due to the abundance of sodium.
• Developing safe and high-performance electrolytes is crucial for advancing SIB technology.
• Phosphate-based materials offer potential for stable and efficient electrochemical performance.

Purpose of the Study:

• To introduce a novel fire-retarding phosphate-based electrolyte for sodium-ion batteries.
• To evaluate the electrochemical performance and stability of the developed electrolyte.
• To investigate the role of vinylene carbonate as an SEI-forming additive.

Main Methods:

• Formulation of a phosphate-based electrolyte: 1 M NaBF4 in triethyl phosphate.
• Inclusion of 3% vinylene carbonate as a solid electrolyte interphase (SEI)-forming additive.
• Electrochemical testing of a sodium-ion full cell (Na3.2V1.8Zn0.2(PO4)3 vs. hard carbon).

Main Results:

• The developed electrolyte demonstrated stable cycling performance in sodium-ion full cells.
• A specific capacity of 80.5 mA h g-1 was achieved.
• A capacity retention of 77.8% was maintained after 200 cycles.

Conclusions:

• The fire-retarding phosphate-based electrolyte with vinylene carbonate shows significant potential for stable and long-lasting sodium-ion batteries.
• The formulation contributes to improved cycling stability and capacity retention.
• This advancement supports the development of safer and more efficient energy storage solutions.