Perhaps, at 14nm and below, when the smartphones and mobile gadgets alike needss recharge current of much less than 500mA, the EMI issue becomes non issue. Or, if energy can be made directional with minute stray radiation, I can really enjoy coffee at Starbuck without any worry of having my brains being "fried".
What are the price to pay: in terms of additional weight and z-height of the coils inside a smartphone. There could be more real estate in a tablet / notebook. My concern is what price to pay in a smartphone.
its easier to standardize a wireless charging protocol than a plug and voltage polarity? what happens when i empty my pocket with a cell phone and Al foil gum wrapper and small length of rolled up wire, im a EE after all, and it bursts into flames?
Three issues that are potential critical: 1) with 5W of EMI radiating, what is the implication to human health especially in confine area like inside a vehicle; 2) all smartphones except those from SJ/Apple use micro-USB for charging anyway, how can consumers (except those using Apple iXs) be benefited; the said efficiency of 70% does not include the AC/DC portion and the aggregate efficiency has to be much lower than whhatever the USB Wall Charger can achieve; so this run against the "green" principle, doesn't it?
This is definitely one of those things that I am eager to see implemented on a wide scale. The freedom to unplug and recharge without constantly looking for the right power cord will be very much welcomed at my house.