University of Arizona reports on "Tiny power generators developed by the University of Arizona and the University of Illinois could eliminate the need for batteries in medical devices.
The miniature devices consist of piezoelectric nanoribbons sandwiched between two thin layers that serve as electrodes, one made of titanium and platinum and the other made of chromium and gold. Piezoelectric elements are crystals that generate an electrical current when deformed under mechanical pressure and are used in many applications, such as disposable lighters and mini speakers."
The mechanical energy harvester, which is flexible enough to conform to the surface of an organ such as the heart, converts the organ's motion into electricity. (Photo: Univ. of Illinois/UA)An energy harverster for an implanted medical device could still though need an energy storage, e.g., for comunicating with the outside world thru wireless communication were more power is need under short period of time.
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SEM a) cross section of a trench array with AR 13:1 filled with MIM stack and b) top down micrograph of Si trench array after silicon etch. Current technology is 1:20 and gives 220nF/mm2 with a goal for 1000nF/mm2 in the near future.