Researchers at the Istituto Italiano di Tecnologia (IIT) have created an edible and rechargeable battery made from materials found in our daily diet. This innovative technology has numerous potential applications in health diagnostics, food quality monitoring, and even edible soft robotics.
The team, led by Mario Caironi of the Printed and Molecular Electronics Laboratory at IIT, has been exploring the electronic properties of food and its by-products to develop new edible electronic materials. Caironi's focus on edible electronics has already earned him a €2 million ERC consolidator grant for the ELFO Project, which explores this exciting new field.
The challenge in developing edible electronics has been to find a way to create power sources that are safe for consumption. The IIT team found inspiration in the biochemical redox reactions that occur in living organisms and developed a battery that uses riboflavin (vitamin B2, found in almonds) as an anode and quercetin (found in capers, among other sources) as a cathode. The electrolyte is water-based, and activated charcoal increases electrical conductivity. The separator, which prevents short circuits, is made from nori seaweed, and the electrodes are encapsulated in beeswax with food-grade gold contacts.
The resulting battery cell operates at 0.65 V, which is safe for consumption and can provide a current of 48 μA for 12 minutes or a few microamps for over an hour. While this may not power a car, it is sufficient to power small electronic devices such as low-power LEDs.
This fully edible rechargeable battery is the first of its kind, and it has many potential applications in the world of edible electronics. Caironi explains that it could be used to power edible circuits and sensors that monitor health conditions, as well as powering sensors that monitor food storage conditions. The team is also working on developing devices with greater capacity and reducing the overall size. These developments will be tested in the future for powering edible soft robots.
The potential uses of this technology are vast, ranging from powering children's toys to providing a safer alternative to current battery technologies. As IIT co-author Ivan Ilic notes, the development of safer batteries without toxic materials is a pressing issue as the demand for batteries increases. The development of this edible battery could inspire other scientists to create safer batteries for a more sustainable future.