Charge batteries through wifi from distance
Charge batteries through wifi, is an article where I have mentioned the background and invention process of charging batteries through wifi. The whole concept is discussed below:
Ikola Tesla was disliked by the cables. He imagined and worked for a world in which they were not necessary. Neither to communicate nor to transmit the energy. The first part of his dream has been fulfilled: there are radio, television, mobile telephony and Wi-Fi networks to prove it. The second part has become more pleasing. But begins to give satisfaction in the form of mats that recharge mobile and systems that feed from the waves of television or mobile.
The next advance in wireless energy has been achieved. That is the system to charge batteries through wifi. Interestingly, thanks to a system designed for communication: the wifi used by most households. A team of researchers from the University of Washington in Seattle (USA) has used a router to charge remote batteries. At the moment they have managed to power devices. Such as those using small appliances and remote controls (nickel-metal hydride batteries). Also, the button cells of the watches (small lithium-ion batteries). The magazine MIT Technological Review collects in an article the study, with an ambitious title: “To feed the next billions of devices with the Wi-Fi ”
The concept of charging batteries through wifi
The system presented there is named PoWiFi (English acronym for “feed through wifi”). It operates at distances up to 8.5 meters. To achieve this. The researchers created a system that collects the energy from the wifi and continuously supplies it to the batteries.
The researchers presume that their achievement is compatible with the usual use of Wi-Fi . Also, it “does not significantly compromise its performance” to connect devices to the Net and to each other. However, for the Radio communication professor at the Polytechnic University of Madrid, José Manuel Riera , this would only be possible in “houses isolated and distant from one another”. Such as those of residential areas of the United States. But, not so much in apartments and floors in which many Europeans live,. Just by the interference of the connection with those of the neighbors.
“When we are not using the Internet, our router only uses 1% of the transmission time. They are disconnections of milliseconds that take advantage of other wireless networks to transmit, “says Riera. The use to supply power, however, requires the router to transmit energy continuously.” In a high usage environment, such as a university or a company, could not be applied “, illustrates the professor.
How does it work?
Unlike the devices that use the television and mobile phone frequencies, this system works with frequencies of the band ISMC (which includes Wi-Fi, but also Bluetooth and ZigBee ). US and European legislation does not limit it’s use to communications. Therefore, could also be used to power small devices, according to the authors.
However, power limitations in Europe (100 milliwatts) and the US (up to one watt, under certain conditions) are very far from what is needed to charge a smartphone. A smartphone needs 4 or 5 volts. To charge your battery for this system, you would have to emit a power a million times greater.
In addition, the waves emitted by a router are broadcasted in all directions (it is precisely the quality that allows them to use devices to connect devices located in various places of a house). But that dispersion plays against the power they are able to transmit.
In spite of the inconvenience, in the opinion of the professor of Electronic Engineering of the Polytechnic University of Valencia, José Sánchez-Dehesa, the investigation is “a significant advance” to keep fed all type of low consumption sensors. Such as those used in home automation and other internet applications. In fact, the study is completed with two new devices . A camera and a temperature sensor – that feed perfectly through the new system. Tesla’s house would have fitted in well.