Edible rice-paper-inspired battery powers medical devices in the body

A battery built from materials resembling edible rice paper can power swallowable medical devices and, once digested, be absorbed by the body. MIT engineer Giovanni Traverso and colleagues tested it in pigs in an RFID transmitter and a stomach stimulator for hunger hormones; results are in Nature Chemical Engineering. Conventional ingested batteries can leak, causing burns or releasing toxins.