Scientists develop edible, rechargeable battery

Researchers from the Italian Institute of Technology (IIT) have created a totally edible, rechargeable battery from materials that are normally consumed as part of a daily diet. The proof-of-concept battery cell was described in a paper published in the Advanced Materials journal. Its possible applications are in health diagnostics, food quality monitoring and edible soft robotics.

Mario Caironi, coordinator of the Printed and Molecular Electronics laboratory of the IIT Centre in Milan, led the study. Caironi has been focusing on the study of the electronical properties of food and its by-products, in order to unite them with edible materials and create edible electronic materials.

The edible electronics field is a recently growing field that could have a positive impact on diagnosing and treating gastrointestinal tract diseases and food quality monitoring. A challenge in the development of edible electronic systems is finding suitable edible power sources.

The researchers developed a battery that uses riboflavin (vitamin B2) as anode and quercetin as cathode. Activated charcoal was used to increase electrical conductivity while the electrolyte was water-based. The separator, needed to avoided short circuits, was made from nori seaweed. The electrodes were encapsulated in beeswax, from which two food-grade gold foil contacts come out on a cellulose derived support.

“Future potential uses range from edible circuits and sensors that can monitor health conditions to the powering of sensors for monitoring food storage conditions. Moreover, given the level of safety of these batteries, they could be used in children toys, where there is a high risk of ingestion. Actually, we are already developing devices with greater capacity and reducing the overall size. These developments will be tested in future also for powering edible soft robots,” Caironi said.

The battery cell operates at 0.65 V, which does not harm the human body 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, such as low-power LEDs, for a limited time.

This research could open the doors to new edible electronic applications.

“This edible battery is also very interesting for the energy storage community. Building safer batteries, without usage of toxic materials, is a challenge we face as battery demand soars. While our edible batteries won’t power electric cars, they are a 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 truly sustainable future,” said Ivan Ilic, co-author of the study.

Image caption: A team of researchers at the Istituto Italiano di Tecnologia (IIT-Italian Institute of Technology) have created a totally edible and rechargeable battery, starting from materials that are normally consumed as part of our daily diet. The proof-of-concept battery cell has been described in a paper published in the Advanced Materials journal. The possible applications are in health diagnostics, food quality monitoring and edible soft robotics. Image credit: IIT-Istituto Italiano di Tecnologia