UCLA 3D-Printed Zinc Battery Stores Seven Times More Energy

A Honeycomb Carbon Electrode

The UCLA team used UV laser stereolithography to 3D print a carbon electrode with a honeycomb-like internal structure. After pyrolyzing the printed resin into pure conductive carbon riddled with open cavities, they loaded it with vanadium oxide. The result is an electrode surface area so large that a single gram, spread flat, would cover roughly ten tennis courts.

'We can actually have billions and billions of these tiny holes, producing an enormous internal surface area. That means we can store a lot of charge,' said Ric Kaner, a UCLA distinguished professor of chemistry and biochemistry.

Hybrid Cell Design

The battery combines two storage modes. One terminal acts like a conventional lithium-ion electrode. The other behaves like a supercapacitor, charging and discharging quickly. By separating the functions but stacking them in one cell, the device delivers both energy density and power density.

Independent testing showed the cell retains 82% of its capacity after 1,500 charge cycles. That is a meaningful number. Most lab zinc batteries fade fast.

A Smarter Test Cell

Alongside the battery, the UCLA group introduced a 3D-printed test cell with a sealed top and fixed electrode spacing. Standard open-beaker setups suffer from evaporation and inconsistent positioning. The UCLA cell is designed to be reproduced by any lab with a resin printer. A premade glass test cell can cost $1,000 or more. A printed version costs pennies on top of printer overhead.

'One of the exciting things about 3D printing is how accessible it has become. In this case, anyone with access to a 3D printer will be able to make a test cell like ours,' said first author Sophia Uemura.

Why Zinc, Not Lithium

Zinc is roughly 100 times more abundant than lithium, easier to mine, and easier to recycle. Maher El-Kady, an assistant researcher in UCLA's chemistry department, framed the work as complementary to lithium, not a replacement. Grid-scale storage is the immediate target, where cost and supply chain matter more than weight.

The study was published in the journal Small and built through a collaboration between UCLA and National Tsing Hua University in Taiwan. Funding came from the University of California Climate Action Seed Grant, Nanotech Energy Inc., and UCLA's Dr. Myung Ki Hong Endowed Chair in Materials Innovation.