Xiaomi says the Mi Air Charge is just in the demo stage at the moment but hasn’t mentioned when it’ll be made available commercially.

Xiaomi says the new Mi Air Charge technology will deliver 5W of power to any device remotely, covering a distance of up to two meters from the “self-developed isolated charging pile.” Multiple devices can be charged simultaneously using this tech, according to Xiaomi. The pile mentioned here is a box that will use beamforming to charge devices remotely. Moreover, any obstacles that come in the way of the pile and the device will not reduce the charging efficiency, meaning that the charging will continue at 5W speed.
How Xiaomi Mi Air Charge works

The Mi Air Charging technology’s pile has 5 phase interface antennas that accurately determines the position of the mobile phone. The phase control array of the pile — composed of 144 antennas — will directionally transmit millimetre-wide waves through beamforming. The receiving device, e.g. a smartphone, must have a miniaturised antenna array with a built-in “beacon antenna” and “receiving antenna array” in order to charge the battery wirelessly. The former tells the pile the smartphone’s position, while the latter is a 14 antenna array that converts the millimetre-wave signal into electrical energy through the rectifier circuit.
Since Xiaomi’s Mi Air Charge technology is just in the demo stage at the moment, we can’t really comment on the implementation problems or whether it will have any implications on health while charging devices wirelessly. While it sure sounds game-changing on paper, the company may face heat during regulations and certifications.