[Figure 1] mimetic diagram of ultrasound passing through the skin to triboelectric device
Professor Sangwoo KIM’s research team claimed that they have developed a new energy harvesting technology that can recharge implantable medical devices using the triboelectric created within the body.
This research was conducted under the auspices of Ministry of Science and ICT’s program and it was published on world renowned journal “Science” on August 2nd.
Title: Transcutaneous ultrasound energy harvesting using capacitive triboelectric technology
Authors: Professor Sang-Woo KIM, Dr. Hong-Joon YOON, Dr. Ronan Hinchet, Dr. Hanjun RYU, Researcher Moo-kang KIM, Professor Eue-Keun CHOI, Dr. Dong-Sun KIM
Implantable devices such as cardiac pacemakers and insulin pump require significant amount of external energy. There had been many efforts to convert the mechanical energy of the body to electric energy but it all failed because the amount of energy produced within the human body was insignificant.
[Figure 2] power performance characteristic of triboelectric device
The research team found a hint in the ultrasound waves used in diagnosis and treatments. They have proved that the external ultrasound causes transformation in a certain material implanted inthe body and the triboelectric caused during this process can be used as a source of energy.
There had been attempts to use the triboelectric from the cardiac impulse of rats and pigs in the past. However, the output was very low that it cannot be used as a source of energy.
The researchers were able to improve the electric current by 1000 times using the ultrasound waves.
[Figure 3] characteristic of energy harvesting and performance depending on the condition of ultrasound
Researchers implanted the triboelectric device in the rat and pig’s skin and induced triboelectric using external ultrasound waves. Through this, they proved that energy harvesting is possible in organic environment.
Furthermore, the team was successful in charging commercial capacitor (4.7mF) and lithium ion battery (0.7mAh).