An Implantable Ionic Wireless Power Transfer System Facilitating Electrosynthesis

A number of implantable biomedical devices have been developed, and wireless power transfer (WPT) systems are emerging as a way to provide power to these devices without requiring a hardwired connection. Most of the WPT has been based on conventional conductive materials, such as metals, which tend to be less biocompatible and stiff. Herein, we describe a development of an ionic wireless power transfer (IWPT) system using hydrogel receivers that are soft and biocompatible. Although the hydrogel receiver has a lower conductivity than metal (ρ gel /ρ metal ∼ 10 –7 ), a capacitive coupling between receiver and transmitter enables the IWPT to deliver 4 mA of current at its resonance frequency. The capacitive coupling through the dielectric and the electrolyte was analyzed including a parasitic effect, and the IWPT was applied to implantable devices to transfer power via the skin. The IWPT sy…