Researchers in South Korea have developed a groundbreaking wireless charging technology that could make life much easier—and safer—for patients with implanted medical devices like pacemakers and neural stimulators.
Led by Professor Jinho Chang from the Department of Electrical Engineering and Computer Science at DGIST (Daegu Gyeongbuk Institute of Science and Technology), the team created a method that uses ultrasound waves to charge medical devices inside the body—without needing surgery to replace batteries.
Their work was recently published in the journal Biosensors and Bioelectronics.
As the population ages and more people require medical implants, one major problem has been how to power them long-term. Current devices use batteries that eventually run out and must be replaced, often requiring additional surgery.
These repeat procedures carry risks and can be stressful and costly for patients. That’s why scientists around the world have been looking for ways to wirelessly send power to devices inside the body.
While the idea of using ultrasound for this purpose isn’t entirely new, existing systems have been limited.
Many previous energy receivers—or “harvesters”—were bulky or inefficient, and the amount of ultrasound energy that can safely pass through human tissue is restricted. This meant they couldn’t deliver enough power to make wireless charging practical.
Professor Chang’s team tackled the issue by designing a new kind of receiver called a “sandwich-structured piezoelectric energy harvester.”
In simple terms, this device has two layers. The first layer collects the incoming ultrasound waves and turns them into electricity.
The second layer picks up leftover ultrasound that the first layer didn’t catch, turning that into additional power. This double-layered system boosts efficiency by over 20% compared to older designs.
In tests, the researchers were able to fully charge a 140mAh commercial battery in just one hour and 40 minutes through water at a distance of 30mm.
In another test, using a 30mm-thick piece of pig tissue to simulate a human body, they charged a 60mAh battery in only one hour and 20 minutes. These results far exceed the performance of previous ultrasound charging technologies, doubling the power output.
Professor Chang explained, “Our research shows that ultrasound—an energy source not fully used before—can be turned into a powerful wireless charging method for devices inside the body.
We’re now working on combining this technology with advanced semiconductors to create a complete system that can fully charge medical implants in under an hour.”
This advancement could mean fewer surgeries for patients and more reliable long-term care, paving the way for a future where implanted devices are easier to maintain and much safer to use.
Source: KSR.
