Nowadays most people have some form of mobile device on their person at all times. With so many useful features it’s easy to see why these devices are seen more and more as essential. With the creation of apps and add-ons for phones, there are more integrative ways than ever to use your mobile devices in your day-to-day life. There are health apps that track medication intake, fitness apps to track your activity levels, and even virtual wallet apps that store your credit cards. So you can see why it might be a problem when you go to leave your home only to reach for a phone that’s low on remaining battery life. What if there was a way you could charge your phone on the go, without the need to carry around an extra battery? More specifically, what if you could charge your phone literally all by yourself?
You’re likely only aware of your own electrical capabilities when you touch something and receive a shock, or when you take off your hat and your hair is standing on end. However, static electricity is produced across our bodies constantly even if we are not aware of it. Static is generated when dissimilar materials come into contact with one another.[i] The more times the two surfaces make contact, the more static is generated; that’s why rubbing materials together can often result in a shock. This processing of electrical charging is called the triboelectric effect.[ii] Even the tiniest amount of interaction between two surfaces is capable of generating static electricity and it’s these types of interactions that researchers at the National University of Singapore hope to use to charge electronics.
These researchers have developed a small generator, roughly the size of a postage stamp, which can be placed onto the skin to generate energy from the friction caused by contact between the skin and the silicone layer of the generator. To maximize friction, the silicone layer has also been covered with thousands of pillar-like structures which will brush back and forth across the surface of the skin. [iii] During tests the generator has been placed on either the throat or the forearm. Placing it on the throat allows it to generate static when the wearer speaks, swallows or breathes, while placing it on the forearm will generate the energy from muscle movements in the arm such as grabbing objects. Throat placement averages about 7.5V during a conversation while a fist clenching motion of the arm generates about 7.3V.[iv] At its current stage, the generator is only capable of producing enough energy to power twelve commercial LEDs, but with future refinements researchers hope to increase the output enough to power mobile devices.
[i] Woodford, Chris. “Static Electricity.” What Is Static Electricity and What Causes It?- Explain That Stuff. 5 Nov. 2014. Web. 23 Feb. 2015. <http://www.explainthatstuff.com/how-static-electricity-works.html>.
[ii] “Triboelectric Effect.” ScienceDaily. ScienceDaily, 1 Jan. 201. Web. 23 Feb. 2015. <http://www.sciencedaily.com/articles/t/triboelectric_effect.htm>.
[iii] McDonald, Glenn. “Skin Patches to Turn People into Batteries.” DNews. 29 Jan. 2015. Web. 23 Feb. 2015. <http://news.discovery.com/tech/skin-patches-to-turn-people-into-batteries-150129.htm>.
[iv] Patel, Prachi. “Skin-Based Generators Scavenge Muscle Motion to Power Wearables.” IEEE Spectrum. 28 Jan. 2015. Web. 23 Feb. 2015. <http://spectrum.ieee.org/tech-talk/biomedical/devices/skinbased-generators-scavenge-muscle-motion-to-power-wearables>.
[v] [Electicity]. (n.d.). Retrieved from https://userscontent2.emaze.com/images/8bd9d449-62ca-4859-b1d6-520987436016/a1530cf5-f3f2-43fb-9375-b4d613c1ee97.jpg
