New, bendable nanogenerators can now turn ultrasound vibrations into energy, providing enough power to keep medical implants working.
A team of researchers from the Korea Institute of Science and Technology (KIST), Korea University, Sungkyunkwan University, Yonsei University, and the University of California has unveiled a method to wirelessly charge implantable medical devices using ultrasonic signals. The technology hinges on an upgraded form of triboelectric nanogenerators (TENGs), which convert mechanical vibrations into electrical energy.
Traditionally, ultrasound-driven TENGs (US-TENGs) have shown promise in converting ultrasound energy into electricity, but they lacked the efficiency needed for real-world use. This new approach changes that. The team’s dielectric-ferroelectric boosted US-TENG design significantly enhances output while maintaining a stretchable and biocompatible structure — crucial features for use in the human body.
In lab tests, the upgraded US-TENGs generated approximately 26 volts DC at 6.7 milliwatts when transmitting through 35mm of tissue — a significant leap in power delivery. Even more impressively, the output increased to 20 milliwatts when tested underwater, opening the door to potential applications in powering underwater drones or aquatic sensor systems.
What sets this US-TENG apart is not just its improved output but its flexibility and durability. The device maintains performance even when bent or stretched, which could make it suitable for recharging more complex implants, including full artificial hearts — a leap beyond the pacemakers and sensors typically targeted by such technology.
As wireless, non-invasive charging becomes increasingly critical for medical implants, this innovation could pave the way for longer-lasting, maintenance-free devices. With commercialization efforts underway, ultrasound-powered implants may soon move from research labs to operating rooms.
“Our research demonstrates that wireless power transmission via ultrasound is no longer just theoretical — it’s practical,” said co-corresponding author Sunghoon Hur. “We are now focusing on miniaturizing and commercializing the technology to accelerate its deployment.”
