Xinhua News Agency, Washington, November 11 (Reporter Lin Xiaochun) — Many consumers are constantly demanding better battery life for their mobile phones. Researchers at Duke University in the United States are developing a new technology that can efficiently convert wireless microwave signals into electrical energy, thereby conveniently charging mobile phones. Some commentators say this means mobile phones may no longer need chargers in the future.
A news release from Duke University explained that, in principle, this technology is similar to solar panels, but instead of converting light energy, it converts microwave signals such as those used in satellite communications and Wi-Fi. The key to its success lies in creating "metamaterials" capable of "capturing" and converting various forms of wave energy.
In experiments, the researchers inserted five fiberglass plates onto a circuit board, then connected them with copper wires to create a simple "metamaterial" circuit capable of "capturing" microwave signals. According to the researchers, this circuit has low manufacturing costs, yet achieves an energy conversion efficiency of 36.8%, comparable to that of solar panels. The device outputs 7.3 volts. In comparison, the output voltage of USB chargers for small electronic devices in daily life is only around 5 volts.
The researchers stated that when the relevant technology matures, such "metamaterial" circuits could be made very small so as to be integrated inside mobile phones, thereby enabling them to harness various microwave signals to charge the devices. "So far, much of the work on 'metamaterials' has been theoretical, but our research shows that metamaterials have great potential in consumer electronics."