Porous Membrane with High Selectivity for Alkaline Quinone-Based Flow Batteries

Area of Science:

• Materials Science
• Electrochemistry
• Energy Storage

Background:

• Aqueous organic-based flow batteries offer safety and cost advantages.
• High-performance membranes are crucial for battery efficiency and cost-effectiveness.

Purpose of the Study:

• To develop a cost-effective, high-performance porous membrane for alkaline quinone-based flow batteries.
• To improve ion selectivity and charge transport (OH-) within the battery.

Main Methods:

• Fabrication of a homemade porous membrane using poly(ether sulfone) (PES) and sulfonated poly(ether ether ketone) (SPEEK).
• Characterization of membrane microstructure and charge properties.
• Testing the membrane in an alkaline alizarin red (ARS)/ferro-ferricyanide flow battery.

Main Results:

• The PES/SPEEK membrane demonstrated excellent ion selectivity and OH- transport.
• The flow battery achieved high coulombic efficiency (98.28%) and energy efficiency (85.81%) at 40 mA cm-2.
• The homemade membrane offered comparable performance to Nafion 212 at a significantly lower cost.

Conclusions:

• The developed homemade porous membrane is a viable, cost-effective alternative for alkaline quinone-based flow batteries.
• This membrane engineering strategy can advance the development of efficient and affordable flow battery systems.
• The findings pave the way for reducing the overall cost of flow battery technology.