Powering devices with the ear's batteries

    In another example of using the body to power implanted devices, I suggest developing a chip powered by the ear.
    The power source for the chip will be an ion-filled chamber within the cochlea, which will be divided by a membrane with some cells specialized to pump ions. The imbalance of potassium and sodium ions on opposite sides of the membrane will create an electrical voltage, which, though low, will be the highest in the body.
    Though the technology is still a long way from practical use, future applications could include drug delivery devices, biomedical sensors for people with balance problems and hearing aids.