|Photo by Norbert Levajsics on Unsplash
Wireless charging has been around since the late 19th century, when electricity pioneer Nikola Tesla demonstrated magnetic resonant coupling – the ability to transmit electricity through the air by creating a magnetic field between two circuits, a transmitter and a receiver.
Wireless charging has been around for a good while now, but it's only in the last couple of years that it's started to take off. More and more manufacturers have got on board with the ubiquitous Qi wireless charging standard and the tech is now inside virtually every flagship phone.
So what exactly is wireless charging, how does it work and does your phone even support it? Allow us to answer all these questions and more.
Samsung has supported wireless charging since the Galaxy S6 and Huawei introduced it with the excellent Mate 20 Pro.
Apple adopted wireless charging with the iPhone X and iPhone 8 and iPhone 8 Plus. Since then it's appeared in the iPhone XS and XS Max as well as in the new iPhone 11 and iPhone 11 Pro as well as iPhone XR and new-generation iPhone SE.
It involves a power transmitting pad and a receiver, sometimes in the form of a case attached to a mobile device or built into the phone itself. When we said it was cable-free, it isn't quite, because the pad will have a cable going from the outlet into it.
|Photo by Mikey Wu on Unsplash
They work on the principle of magnetic induction.
What is magnetic induction?
The definition goes like this “phenomenon in which an EMF get generated in a coil due to a variance in the flux associated with it, which in turn gives rise to a varying current is called Magnetic induction, which lasts as long as the change in flux takes place"
Flux is basically the number of magnetic field lines associated with a coil. Whenever you bring a source of a magnetic field near it (like bar magnet) the "flux" , which in turn gives rise to an EMF.
As long as this change in the magnetic field, you can notice this EMF in the coil that we are talking about.
Now back to wireless charging. The dock that you use for wireless charging has a coil in it, and the back of your phone (if it supports wireless charging) also have a coil similar to this .
When you plug-in your dock to the source of alternating current , the flux associated with the coil in the dock begins to vary because as the name suggests "alternating" current.
This "alternating" current gives rise to a varying magnetic field in the coil.
Now your "primary" coil begins to function as the source of varying magnetic field.
Many car manufacturers have wireless charging in certain models, but even then it often isn't as standard and tends to be on models further up the range. The manufacturers using it include Audi (and the rest of the WV group), BMW, Ford, Honda, Mercedes-Benz, Peugeot, Toyota, and Volvo.
Advantages of wireless charging-· Safer way to transfer power to your phone.
· Simple to just drop your phone on the charging pad.
· Puts less strain on the charging port of your phone.
· Qi wireless charging pads being installed in various places around the world, if you run out of juice and don't have a cable you can still charge your phone.
Disadvantages of wireless charging
- · Wireless charging is slower, especially for phones with Quick Charge technology - plugging into a wall outlet will be much, much quicker for those devices.
- · If you've got your phone charging via a cable, you can still hold it and use it as normal. If you take your phone off a wireless charging pad to use it, it stops charging.
- · Not all phones have it.