3D-printed lab electrode boosts flow-battery performance 52%

A porous black structure sits in the hands of Maxime van der Heijden, a University of Waterloo professor, after being printed and before heat treatment. Inside a laboratory battery, the structure is designed to move liquid more effectively—and the team reports that its best version increased performance by 52%.

The component belongs to a redox flow battery, or RFB, which stores electricity in liquid electrolytes held in external tanks. Unlike the flammable materials used in lithium-ion batteries, these electrolytes are water-based, making RFBs a potentially safer option for large-scale storage. Their energy capacity can also be increased by using larger tanks, according to van der Heijden.

The researchers used digital light-processing 3D printing to control the electrode’s pores and internal pathways. They tested several triply periodic minimal surface, or TPMS, geometries—complex repeating three-dimensional shapes—and found that the “diamond” design moved the battery liquid most effectively. After heat treatment, the printed structures became conductive carbon electrodes.

The team tested the electrodes first in laboratory flow cells and then in a working vanadium redox flow battery, showing that the printed designs can function in an operating battery; the work remains a proof of concept. The study appears in the Journal of Energy Storage.

So what changes in practice? If the design scales, it could help grid operators and communities store surplus electricity from wind and solar and return it to the grid later, using a battery architecture whose storage volume is expanded with tanks. The immediate next steps are more surface area, better manufacturing and further testing—not a ready-to-install product.