Researchers at the Binghamton University in New York developed their origami battery with a view to powering low-energy devices where electricity isn’t so readily available. Powered by the bacteria in a few drops of dirty water through the process of bacterial metabolism, the paper-based battery could be built to run a biosensor in the field at a cost of just five US cents.
Where the original design folded up like a matchbook with four modules laid on top of one another, the latest iteration packs eight batteries into a sliding, star-shaped frame. Within each of the modules are paper layers, an anode, proton exchange membrane and an air-cathode, while in the center is an inlet where the dirty water is fed.
As the battery is pulled apart into a donut-shape, fluidic pathways running through the paper layers carry the water into the eight fuel cells and kick off the electricity-producing chemical reaction. This state also allows the separate battery modules to connect with one another, which improves power output and also exposes the air-breathing cathodes to the air.