Implanted Carbon Nanotubes Harvest Electrical Energy from Heartbeat for Medical Implants

Reliability of power supply for current implantable electronic devices is a critical issue for longevity and for reducing the risk of device failure. Energy harvesting is an emerging technology, representing a strategy for establishing autonomous power supply by utilizing biomechanical movements in human body. Here, a novel "Twistron energy cell harvester" (TECH), consisting of coiled carbon nanotube yarn that converts mechanical energy of the beating heart into electrical energy, is presented. The performance of TECH is evaluated in an in vitro artificial heartbeat system which simulates the deformation pattern of the cardiac surface, reaching a maximum peak power of 1.42 W kg^-1 and average power of 0.39 W kg^-1 at 60 beats per minute. In vivo implantation of TECH onto the left ventricular surface in a porcine model continuously generates electrical energy from cardiac contraction. The generated electrical energy is used for direct pacing of the heart as documented by extensive electrophysiology mapping. Implanted modified carbon nanotubes are applicable as a source for harvesting biomechanical energy from cardiac motion for power supply or cardiac pacing.