Wearable electricity generator

Collecting statics from human skin, the new flexible generator is capable of producing enough current to power small electronics: for example, medical sensors, a LED or even a fitness tracker! That is, it can simply be attached to the body - and never recharge the batteries.

This is a very promising prototype of the developers from the National University of Singapore presented at the recent conference IEEE MEMS 2015 . At the conference, it was shown exactly how a fitness tracker works on such a generator, writes IEEE Spectrum. In open access, the scientific work has not yet been published.
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The news has passed by the attention of many media, although it is an extremely important device. Getting enough electricity from the human body is one of the most promising tasks of modern science. Such technology will greatly affect human civilization, changing lifestyle, people's habits and, among other things, providing them with convenient medical sensors that will save millions of lives, and other wearable electronics.

Engineers have long tried to make effective nanogenerators for the body. For example, for this purpose , MoS _2- type piezomaterials were used , which produce current by mechanical action, stretching and compression.

But in 2012 it was announced a new type of generators using the triboelectric effect, the electrification of bodies as they approach them very close to each other. In this case, not the surface of both bodies is collected static electricity.

Some people even tried to make a nanogenerator that looked like a Slinky toy . This pressure sensor does not require external power. Energy comes simply from compression and stretching during operation.

The National University of Singapore went even further. They decided to use human skin as one of the triboelectric layers. The second layer is thousands of nanometer-sized pillar structures (to increase the area) with a flexible rubber layer. Under the rubber - a thin layer of gold film with a thickness of 50 nm, it acts as an electrode.

Such a film can be attached to any place on the skin that is constantly in motion (that is, where the pulse is felt, for example, on the neck or wrist). Engineers glued it to the wrist, and when the fist was pressed, the generator gave out 7.3V. If you attach it to your neck, then during a conversation 7.5V is issued.

The largest current of 90V / 0.8 mW was obtained if you touch the generator with your finger. This current is enough to power 12 commercially available LEDs on the market now!

Naturally, the currents grow if you increase the size of the film or the density of the pillar-like structures inside. The film is completely harmless to the skin. It is terrible to imagine how much electricity will come out if you wrap large areas of the body with it.