Energy Harvesting in In-Vivo Devices

Abstract

New methods of powering in-vivo devices would enable the development of new medical implants and ingestibles capable of monitoring and treating previously inaccessible parts of the body. Wire- less power transfer could allow batteries to be safely recharged without invasive procedures, and batteries that utilize gastric fluid as an electrolyte could be a cheap and efficient way of powering ingestible sensors. Therefore, we simulated a resonant coupling circuit and tested a gastric battery in order to determine if they could provide the power needed for medical devices. We were able to simulate a resonant coupling circuit with rectifier that harvested 0.7-0.8V of DC voltage from an external AC voltage of 10V. Our gastric battery had an open-circuit voltage of 960mV and could provide 13μW of power to a CMOS biosensor chip.