Have you ever dreamed of cell phones that don't need to be recharged? Well, someone has opened their eyes and is trying to build one. To be precise, researchers at the University of Washington have already done it a paper and a prototype cell phone that tests all the technologies needed to make it work without a battery.
A few micro-watts of electricity "dance" between it and the final version, still necessary to power the circuits responsible for the calling functions, but the researchers say they are confident that they will soon be able to cut this last "chain" too.
How does it work, and what are the limitations?
The system has been designed to optimize speech transmission and reception in terms of energy consumption. In fact, the cell phone also functions as a "harvester", using its internal antenna to capture energy from electromagnetic signals radiated from a base station. The plan is to ensure that the energy collected in this way is sufficient to ensure the continuous functioning of cell phones and similar devices. In other words, an idea even more advanced than that which contemplates the "remote charging” currently in the testing phase.
Still at the moment, obviously, the prototype is conceptually closer to a cordless phone. The only significant limitation is that it works up to 9,4 meters away from the base station, while the use of solar power extends its range up to 15,2 meters. From here on, however, only the positive news begins. Starting from the fact that the prototype is made with standard electronic components and mounted on a normal printed circuit board.
Will we really have cell phones without batteries?
The developer team also demonstrated the ability to make the first Skype call over a cellular network with a custom base station. As mentioned, the engineers on the project page (that I link to you here) believe this is only the first step and plan to extend the operational range in the future, which would be a significant step towards completely battery-free cellphones and other communication devices.
