Charged Up Over Wireless

Portable technology is great but cables, and specifically charging cables, suck. They’re never where you need them, traveling around with them drastically shortens their life, and there are just enough different types to ensure you’ll be left searching through a drawer for the correct one. Happily, wireless charging has entered the fray and is now a totally viable alternative to digging around in that cable drawer for just the right type of USB cable. It’s quick, it’s safe and it’s widely available. How then does the magic happen? How’re we transmitting electricity without the use of plugs and wires? Can we really ditch cables for good?

While there are a few different flavors of wireless charging standard, let’s first look at how the technology works as a whole. Wireless chargers use induction to operate; this inductive charging works by using an electromagnetic field to transfer energy between two objects - a charging pad and the device being charged. The charging pad contains a coil of wire that generates an electromagnetic field, and the device being charged has a second coil which receives that energy and converts it back into an electrical current. Some of this energy during this process is lost to heat, which is actually one of the major downsides to wireless charging in general; it’s quite inefficient compared to a simple wire.

To combat these inefficiencies and maintain compatibility between charging hardware and the devices people like to charge, certain standards have been developed. The most common of these is Qi, pronounced “Chee.” Qi is by far the most widely adopted wireless charging standard, developed by the Wireless Power Consortium back in 2008. It is used by many smartphone manufacturers, including Apple, Samsung, and LG, which is great for multi-device households as you’d only need one type of charger for all sorts of device. The most modern iteration of Qi supports up to 15W of charging, but individual devices will vary on how much of that they’re able to take advantage of.

It actually wasn’t until 2012 that cellphones adopted wireless charging, with Nokia’s 920 handset. 2015 saw Samsung offer the feature on its Android devices while Apple added wireless charging, first in 2014 with their Apple Watch, then in 2017 with the iPhone 8. Apple, it’s worth noting, now have their own wireless charging technology called MagSafe. A little confusingly, they also use this nomenclature for their magnetically-secured MacBook chargers, MagSafe for your iPhone (and now AirPods) uses a magnetic ring to secure a charger or other accessory to the back of your phone, centering properly over the charging coil. This allows generally faster wireless charging, as well as being backwards compatible with Qi. Being an iPhone user myself, it’s genuinely a feature I make full use of.

The natural progression of this is of course, wireless power from further afield than laying a device on a charging pad. Systems like this are in development, but are so inefficient right now that they aren’t much use beyond very low powered devices at very conservative distances. With battery technology continuing to improve, we’re of course less tied to needing chargers in general. It will be nice when we’re finally free of being tethered to a USB port altogether, but for now, wireless charging’s sufficiently Jetsons for me.