HOW IT WORKS - Reverse wireless charging

How your iPhone could one day charge your AirPods without wires

- Carrie Marshall

With the launch of the new iPhone 13 at Apple’s September event, we were hoping to see one much-wanted feature: reverse wireless charging. Unfortunately, while the technology has apparently been found in the iPhone 12 (according to the US Federal Communications Commission) and can be used to reverse charge Apple’s MagSafe Battery Pack, it hasn’t been made more widely available. So what is it and how does it work?

How wireless charging works

Wireless charging isn’t exactly new: it was first demonstrated over 100 years ago by Nikola Tesla, and if you have an electric toothbrush you’ve probably got a wireless charger in the bathroom. The technology hasn’t really changed much over the decades. It’s just got more efficient. When we talk about wireless charging in a phone or tablet context, we’re talking about using electromagnetism: it’s possible to transmit electricity via radio frequencies, but it isn’t powerful or practical enough for everyday use.

Electromagnetic charging consists of a transmitter and one or more receivers. The transmitter, which is your wireless charging pad or puck, creates an oscillating magnetic field. When they’re close enough, that magnetic field induces a current in the coiled wire loops inside the receivers. That current can then be used to recharge the battery or even power small electronic devices.