Chinese OEMs like Xiaomi and OPPO seem to be locked in a race for the best smartphone charging speeds, some of them even going to seemingly dangerous extremes. For now, though, it seems that Xiaomi has just gotten the upper hand with the revelation of the Mi Air Charge that takes wireless charging to its logical next step. The fine details may be a bit disappointing but it could still serve as the foundation for the company’s future technologies not just in mobile but in IoT as well.
Wireless charging might be quite common now but it is still far from the ideal many of us might have in our heads. The transfer of electricity itself might be wireless but current standards like Qi still require a very narrow gap between charging coils that they practically touch each other. Even worse, some implementations require very specific placement of devices, something Apple’s MagSafe tries to solve.
In an ideal world, true wireless charging will be similar to wireless communication, happening over the air and over great distances. There have been a few research attempts at achieving that but none have so far made it to commercial applications. Xiaomi, however, may have reached a breakthrough, at least enough for it to put a name on the technology and reveal it publicly.
Calling it Mi Air Charge, the truly wireless charging technology utilizes dozens of antennas to make it happen. The rather large charger has five phase interference antennas that detect the location of a smartphone while 144 other antennas transmit millimeter-wide waves in the phone’s direction. The phone, on the other hand, has a beacon antenna that broadcasts its location and 14 receiving antennas that convert those millimeter waves into electricity to charge the phone.
As impressive as that may look, there are a few details that may make the Mi Air Charge sound less ideal. For one, charging tops at 5W, probably for safety. It is also currently still an experiment by Xiaomi, like its 100W wired charging years ago, so it might take some time before it even becomes ready for commercial use.