One-step generation and characterization of perfluorohexanone emulsions via modified Tessari method for sodium...

Area of Science:

• Materials Science
• Chemical Engineering
• Fire Safety Engineering

Background:

• Lithium-ion battery fires present significant safety risks due to rapid heat release.
• Perfluorohexanone (PFH) is an effective fire suppressant but its volatility necessitates improved delivery systems.
• Sodium alginate (SA)-based microcapsules offer a potential solution for stabilizing PFH, but emulsion formation is challenging.

Purpose of the Study:

• To develop a stable Perfluorohexanone (PFH) emulsion for microcapsule fabrication.
• To manufacture high-performance PFH@SA microcapsules for lithium-ion battery fire suppression.
• To optimize the microencapsulation process using a modified Tessari method.

Main Methods:

• A modified Tessari method using two syringes was employed for one-step PFH emulsion preparation.
• Systematic comparison of emulsion stability between the modified Tessari and classical stirring methods.
• Investigation of parameters including viscosity, surface tension, flow rate, voltage, and frequency on microcapsule properties.

Main Results:

• The modified Tessari method demonstrated superior efficiency and emulsion stability compared to the classical stirring method.
• Viscosity was identified as the dominant factor influencing jetting modes, with moderate flow rates (2.5 mL/min) and a 1:4 core-to-shell ratio optimizing microcapsule formation and encapsulation.
• The fabricated PFH@SA microcapsules showed significant potential in suppressing battery thermal runaway events.

Conclusions:

• The modified Tessari method provides an effective approach for fabricating stable PFH@SA microcapsules.
• Optimized process parameters are crucial for achieving high encapsulation efficiency and desired microcapsule characteristics.
• These microcapsules hold promise as an advanced fire suppression agent for lithium-ion battery applications.