Scientists at the Italian Institute of Technology made the battery from food products.
The separator, made from nori seaweed, prevents short-circuiting, and the electrodes are encased in beeswax, with two edible gold leaves.
Moreover, the battery operates at 0.65 volts and can power a small LED, or other miniature electronic devices.
Researchers hope the edible battery could revolutionise ingestible medical devices, and have a major impact on diagnosing and treating gastrointestinal conditions, as well as monitoring food quality.
Ingestible devices already exist, but can't be digested by the human body.
The Italian Institute of Technology says their device can be completely digested without health risks.