A team led by Mario Caironi, coordinator of the Printed and Molecular Electronics Laboratory at the Istituto Italiano di Tecnologia, has developed the world’s first rechargeable edible battery, which has great potential for use in health diagnostics, food quality monitoring , and the eventual creation of edible soft robotics.
A major challenge in the field of edible electronics has been the creation of edible power sources. Taking inspiration from biochemical redox reactions, the research group developed a battery that uses riboflavin (vitamin B2) as an anode and quercetin (a food supplement and ingredient) as a cathode. Activated charcoal was used to increase electrical conductivity, and the electrolyte was water-based. The separator, required to avoid short circuits, was made from nori seaweed. Electrodes were encapsulated in beeswax from which two food-grade gold contacts (the foil used by pastry chefs) on a cellulose-derived support emerge.
The battery cell operates at 0.65 V, a low voltage which does not create problems when ingested. It can provide a current of 48 μA for 12 minutes, or a few microamps for more than an hour, enough to supply power to small electronic devices for a limited time.
“This edible battery is also very interesting for the energy storage community. Building safer batteries, without the usage of toxic materials, is a challenge we face as battery demand soars. While our edible batteries won’t power electric cars, they are proof that batteries can be made from safer materials than current Li-ion batteries. We believe they will inspire other scientists to build safer batteries for a truly sustainable future,” stated Ivan Ilic, coauthor of the study.