Binghamton scientists 3D print stainless-steel biobatteries
New metal anodes enable greener, tougher microbial energy systems
According to Binghamton University‘s Professor Seokheun “Sean” Choi, engineering breakthroughs often demand trial and error, but occasionally the solution is closer than expected – even downstairs. Over the past decade, Choi has developed bacteria-powered biobatteries, but progress has been constrained by material limitations.
While seeking a custom stainless-steel component, Choi discovered that Assistant Professor Dehao Liu – just a floor below – specializes in laser powder bed fusion (LPBF), a method ideal for printing stainless-steel microarchitectures. “LPBF is ideal for biobatteries because it enables high-precision, customizable 3D structures with complex geometries, essential for maximizing surface area and energy density,” Liu said.
Their collaboration, published in Advanced Energy & Sustainability Research, describes biobatteries designed to power small, autonomous devices like IoT sensors. Other contributors include ECE Assistant Professor Anwar Elhadad, PhD student Yang “Lexi” Gao, and Liu’s PhD students Guangfa Li and Jiaqi Yang. The project is funded by Choi’s 2024 NSF grant.
Endospores, a dormant form of bacteria, fuel the biobattery through an electrochemical reaction. For optimal performance, the anode (where bacteria live) must be 3D so the microbes can thrive. “A two-dimensional anode is not efficient,” Choi said.
Stainless steel mesh proved better than carbon or polymer-based materials, which are fragile and poor conductors. But commercial mesh lacks control over porosity and roughness. LPBF solved that. “We saw the potential here,” Choi said. Using 3D printing, they also fabricated components like the sealing cover and cathode, assembling the battery “like Lego bricks.”
The batteries can be stacked to boost power, reaching nearly 1 milliwatt – enough to run a 3.2-inch LCD. It’s one of Choi’s highest-yielding designs. Plus, stainless steel allows for bacteria reuse: “We showed after a number of uses that power levels are maintained.”
The Binghamton team’s next steps: unify the printing of all components and develop a power management system to optimize charging and discharging – like a solar cell.
