Waterloo Researchers 3D Print Battery Electrodes That Store Renewable Energy Better

A geometry that stores more energy

Researchers at the University of Waterloo have 3D printed a new type of electrode that could make grid-scale renewable energy storage cheaper and safer. The key is a repeating three-dimensional shape borrowed from nature.

The team, led by chemical engineering professor Dr. Maxime van der Heijden, used a digital light-processing 3D printer to build porous carbon structures based on triply periodic minimal surface (TPMS) geometries. These are complex, repeating patterns that appear in things like butterfly wings and cell membranes. After printing, the structures were heat-treated to become conductive electrodes.

Of the designs tested, the diamond geometry worked best. When installed in a vanadium redox flow battery, it increased performance by 52 percent compared to conventional electrodes.

Why redox flow batteries matter

Redox flow batteries store energy in liquid electrolytes held in external tanks, not in solid materials like lithium-ion cells. That means you can scale capacity simply by using larger tanks. The water-based electrolytes also make them safer than lithium-ion systems, which is important for community-scale storage.

The catch has always been efficiency. The liquid needs to flow evenly across the electrode surfaces for the chemical reactions to work well. Conventional manufacturing methods cannot create the fine internal structures that help with that flow.

3D printing changed the equation. With it, the Waterloo team could design exactly how liquid moves through the electrode. The TPMS diamond pattern creates a sponge-like network that spreads electrolyte across more surface area.

What comes next

The researchers have proven the concept in lab flow cells and in a working vanadium redox flow battery. Next steps include increasing the electrode surface area further, improving the manufacturing speed, and using AI design tools to generate even better geometries.

The study appears in the Journal of Energy Storage under the title "Enhancing Mass Transport in Redox Flow Batteries with 3D-Printed Triply Periodic Minimal Surface Electrode Structures."