How can we make batteries in medical devices safer and lessen their impact on the human body? Recently, Italian scientists have developed a completely edible and rechargeable battery that can be safely ingested.
Edible electronics is an emerging field that has benefits for diagnosing gastrointestinal diseases, medical treatments, and food quality monitoring. One of the most interesting challenges in the development of edible electronic systems is achieving a power source that is entirely safe for human consumption. A team led by Mario Caironi, a senior researcher at the Italian Institute of Technology, has created an experimental edible battery. They were inspired by the biochemical redox reactions that produce energy in human and animal cells.
The team’s new edible battery features an anode and cathode composed of natural materials, such as riboflavin (vitamin B2) derived from almonds and quercetin found in tartary buckwheat. Activated charcoal was incorporated to help boost electrical conductivity. The battery also used a water-based electrolyte and a separator made from nori seaweed—a common ingredient found in sushi—ensuring that all components were non-toxic and safe for consumption. The electrodes were encased in beeswax, and two food-grade gold foil contact points were situated on a cellulose-derived support structure to finish off the overall design.
The battery has a working voltage of 0.65 volts and operates without issue inside the human body. It can produce a 48-microamp current for 12 minutes or a few microamps for one hour, which doesn’t sound like much, but it’s enough to power small electronic devices such as low-power LEDs.
Caironi says that potential uses in the future include edible circuits and sensors for tracking health conditions, and sensors for monitoring food storage conditions. In addition, considering how safe these batteries are, they could also be used in children’s toys that are often ingested during play. The team is currently developing smaller devices with larger capacities.
(Image Source: Italian Institute of Technology)