A team of researchers at the Italian Institute of Technology (IIT) has created a totally edible and rechargeable battery, starting from materials that are normally consumed as part of our daily diet.
The IIT’s research group, led by Mario Caironi, coordinator of the Printed and Molecular Electronics laboratory, took inspiration from the biochemical redox reactions that happen in all the living beings, and developed a battery that utilizes riboflavin (vitamin B2) as anode and quercetin (a food supplement and ingredient) as cathode. Activated charcoal (a widespread over-the-counter medication) was used to increase electrical conductivity, while the electrolyte was water-based. The separator, needed in every battery to avoid short circuits, was made from nori seaweed, the kind found in sushi. Then, electrodes were encapsulated in beeswax from which two food-grade gold contacts (the foil used by pastry chefs) on a cellulose-derived support come out. The battery cell operates at 0.65 V, a voltage low enough not to create problems in the human body when ingested. It can provide current of 48 μA for 12 minutes, or a few microamps for more than an hour, enough to supply power to small electronic devices, such as low-power LEDs, for a limited time.
IIT-Italian Institute of Technology, Milan, Italy
One of the most interesting challenges in the development of future edible electronic systems is to realize edible power sources. This battery offers a potential solution.
The fully edible rechargeable battery could open the doors to new edible electronic applications in health diagnostics, food quality monitoring, and edible soft robotics.