Ultrasound system recharges pacemakers without invasive surgery

A research team at the Daegu Gyeongbuk Institute of Science and Technology (DGIST) in South Korea, led by Professor Jinho Chang, has developed a novel ultrasound-based wireless charging system for implantable medical devices such as pacemakers. This system uses dual piezoelectric layers to capture and convert ultrasound waves into electricity with over 20% higher efficiency than previous methods. The device achieved a power density of 497.47 milliwatts per square centimeter in water and a total output of 732.27 milliwatts, enabling it to fully charge a 140mAh battery in just 1.7 hours without invasive surgery. The technology was tested under realistic conditions using 30mm-thick pig tissue to simulate human anatomy, where it still delivered 312.34 milliwatts. In practical experiments, the system fully charged a 140mAh battery in 1 hour and 40 minutes underwater at a 30mm distance, and a 60mAh battery