Breathing is a unrealizable, silent activity that forms the basis of all living beings on earth. But what if the mechanics of human breathing could produce electricity? Sounds unrealistic, but the answer is yes! Materials Science and Engineering Assistant Professor Xudong Wang, postdoctoral Researcher Chengliang Sun and graduate student Jian Shi report from the University of Wisconsin – College of Engineering have manufactured a device that could be used to capture energy from respiration.
There have a been a lot of recent developments on the front of using human anatomy to generate electricity. While some utilize piezoelectric crystals to generate electricity from a person’s body movements, others like biological fuel cells possess the capability to produce electricity from sugar level of a person. However, this time, the device devised by University of Wisconsin relies on the piezoelectric effect. The piezoelectric effect makes use of the airflow caused by respiration to produce electrical impulses which can power biological implants. Even a slow airflow can result in vibrations on the plastic micro belt engineering inside the device made up of polyvinylidene fluoride (PVDF).
Though the airflow of respiration is as slow as two meters per second, if the width of the material belt is thin enough, then the vibrations can produce a micro-watt of energy. The duo team have used the ion-etching process to thin the material while maintaining its piezoelectric properties. With improved efforts, the material can be thinned to a sub micron level. Presently the device produces electricity up to 6 millivolt when the airflow is maximum.