A Body Conformal Ultrasound Receiver for Efficient and Stable Wireless Power Transfer in Deep Percutaneous Charging

Wireless powering of rechargeable-implantable medical devices presents a challenge in developing reliable wireless energy transfer systems that meet medical safety and standards. Ultrasound-driven triboelectric nanogenerators (US-TENG) are investigated for various medical applications, including noninvasive percutaneous wireless battery powering to reduce the need for multiple surgeries for battery replacement. However, these devices often suffer from inefficiency due to limited output performance and rigidity. To address this issue, a dielectric-ferroelectric boosted US-TENG (US-TENG_DF-B) capable of producing a high output charge with low-intensity ultrasound and a long probe distance is developed, comparatively. The feasibility and output stability of this deformable and augmented device is confirmed under various bending conditions, making it suitable for use in the body's curved positions or with electronic implants. The device achieved an output of ≈26 V and ≈6.7 mW output for remote charging of a rechargeable battery at a 35 mm distance. These results demonstrate the effectiveness of the output-augmented US-TENG for deep short-term wireless charging of implantable electronics with flexing conditions in curved devices such as future total artificial hearts.