Awesome discovery in revolutionary charging technology

Image courtesy of Jorge Franganillo at Flickr.com

Researchers from the Autonomous University of Barcelona, have designed a system of wireless charging for mobile devices, which allow longer distances of charging compared to the actual functioning system, with greater efficiency. This model is developed with materials surrounding the emitter and receiver. The wireless charge in mobile devices is probably one of the technological milestones with more research. Actually, there are already working devices that allow wireless charge, by placing the mobile in a charging base. The next step is to charge the mobile without ever taking it out of the pocket. This step is yet to be reached. But a team in the Physics Department from the Autonomous University of Barcelona developed a system capable of transferring electrical charge with high efficiency, between two separated circuits, using meta-materials. It is a system in experimental phase, should it be optimized and the load applied to mobile devices, it will allow the desired wireless charging at distances greater than today.

The induction phenomenon is the principle that allows the wireless charge for mobile devices, using a special case, adapted to the device and a base connected to the electrical grid. When the mobile is placed on the base, this generates a magnetic field that induces an electrical flow in the case, and without the need of a wire the battery begins to charge.

If the mobile is separated from the base, the energy is not transmitted with sufficient efficiency and battery cannot be charged. The new system developed by the research in Barcelona overcomes limitation. It is constructed with meta-materials that combine layers of ferromagnetic materials, like the magnets, and conducting materials, like copper. The meta-materials surround the emitter and receiver circuits and allow the transference of energy between them at a certain distance, with remarkable efficiency.

Image courtesy of Jim Pennucci at Flickr.com

With the use of the crowns of meta-materials, researchers have managed to increase the transference efficiency up to 35 times in the laboratory. Álvar Sanchez, the director of the research said: “and there is still a lot of room for improvement, since the theory tells us that efficiency can be increased considerably if we optimize the conditions and the experimental design is perfected”. The lead author of the article, Jordi Prat, explained “Surrounding the two circuits with the crowns of meta-materials, has the same effect as bringing them closer, as if the space between them became shorter”. Furthermore, the materials used to build the meta-materials, like copper and ferrite, are very common and easy to find. The early experiments in this direction, to concentrate static magnetic fields, required the use of superconductors, beyond the reach of day to day use for mobile devices. “Instead, with the use of low frequency electromagnetic waves, like the ones with use to transfer energy from one circuit to another, we just need conductors and conventional magnets”. Said Carles Navau.

In the patent process, participated Àlvar Sanchez from the Department of Physics Electromagnetism in UAB, with Academy and ICREA (Catalan Institution for Research and Advanced Studies) researcher Carles Navau, along with Jordi Prat, currently at the Institute for Quantum Optics and Quantum Information of the Austrian Academy of Sciences in Innsbruck (Austria). The device has been patented by the UAB and there are companies from several countries interested in applying this technology. The research was funded by a Producte project of the Generalitat de Catalunya, for ERDF (European Regional Development Fund) and the Ministry of Economy and Competitiveness.

The already achieved distance: 20 centimeters

A group of scientists from the ITMO University (St. Petersburg) and the Giricond Research Institute (both from Russia) proposed a wireless charging system with transfer efficiency of 80% at a distance of 20 centimeters. This was three months ago. The results were tested experimentally with a light emitter diode, which scientists managed to turn wirelessly. The system replaces the copper coils traditionally used with spherical dielectric resonators made of ceramic material with low loss and high permittivity. This step that prevents loss of metals, achieves greater efficiency.

Another innovation was to use resonant frequencies of higher order modes called magnetic quadrupole (A quadrupole or quadrapole is one of a sequence of configurations of electric charge or current, or gravitational mass that can exist in ideal form, but it is usually just part of a multipole expansion of a more complex structure reflecting various orders of complexity). The group found that the system operation quadrupole mode, rather than in the dipole mode, not only increases the system efficiency, but also makes it less sensitive to random orientation of the transmitter relative to the receiver.

The possibility of random orientation is an important step to achieve wireless charging stations of practical commercial use. Today, the wireless charging requires perfect alignment between the device and the charging base. The quadrupole mode does not require such precision. The researcher Polina Kapitanova stated that “This is just a pioneering work, but our experimental configuration now works with distances up to 20 centimeters and 1 watt of power”.