Everything you wanted to know about wireless charging

Category: Features

I’m sure it comes as no surprise to you all that around the office I’m “the tech guy”. If you’ve got a phone that isn’t doing what you want it to or a USB device that you don’t know which cord to buy for it the likelihood is that you’ll saunter over to my desk and slip into my workday like a thirsty tween on your crush’s Insta DMs.

My point is when someone across the way piped up and asked “What wireless charger should I buy for my iPhone?” the other day I was stumped. I own zero wirelessly charging devices… zero! Can you believe it?! In this day and age I pick myself up, fumble about for a cord and this laboriously plug the thing in like a Neanderthal.

Not knowing the answer and like any good nerd, never willingly admitting that I didn’t know, I simply said “I’ll get back to you” and messaged the tech guy’s tech guy, Mr Sizzle himself, Anthony Agius.

Ant’s reply was, as always, succinct and to the point – and unlike this article not four paragraphs worth of drivel to get to the guts. He wrote, “Basically any Qi charger will work with an iPhone, just get one you reckon looks nice & won’t burn your house down”.

To be fair, I thought it was going to be a little more complicated than that. I knew of “Qi” as a standard but then what was its other and should I care about it? There’s no dramas with voltage and watts? How can this all be so straight forward? And so I decided to dive into it some more and find out exactly what the deal is with wireless charging is in 2019 and answer the most common questions around it.

What is wireless charging?

Wireless charging as we know and love today is more accurately known as “inductive charging“, which in itself comes in two varieties – low power (devices under 100 watts) and high power that can charge at a power level of over 1 kilowatt.

The first known application of the technology was way back in 1978 when a group of scientists made an electric vehicle that was powered by a 180Hz 20kW system.

In the 1980’s a Californian bus was produced that used inductive charging and from the 90s to today its been hiding in plain sight working to charge your electric toothbrush – if it was made by Oral B.

Other forms of wireless charging such as “conductive charging” exist but are more complicated and have requirements such as contact being made directly to the battery and have not been as widely applied in today’s consumer market.

How does wireless charging work?

Without getting too technical it’s all about the magnets. Wireless “inductive” charging works by including an inductive coil in both the charging base and the device that’s to be charged.

The coil in the charging base takes power from your home and uses it to create a small alternating electromagnetic field. When an equipped device enters thats field its own inductive coil uses that electromagnetic field to draw power from and converts in back into an electric current which in turns chargers a battery.

When both coils are in proximity to one another they’re essentially creating an electrical transformer. The main difference being the tech that makes up that transformer is actually split between two devices.

Is wireless charging safe?

This is a pretty fair question and if you’re a lover of “Better Call Saul”, one that probably came to you quicker than others.

The short version here is yes, it’s safe. Safe just like mobile phones are safe, just like microwaves and WiFi and every other of the million bits of low energy electromagnetic fields (EMF) we walk through everyday are.

In the case of wireless chargers the EMF they generate are limited in space operating over very small distances. Most inductive chargers will include (or they should if they’re made responsibly) some level of shielding around its coils as is the same in the device’s being charged.

Some argue it may even be safer as wireless charging devices are devoid of any openings that could allow exposure to an electrical current. Their unique ability to remain enclosed also means wireless charging is being adopted by the medical community for devices embedded within you.

What wireless charging standards are there?

Like Beta and VHS or HD-DVD & BluRay the wireless charging world has had its rivals but unlike those the Qi (pronounced ‘chi’) standard has largely won and was largely considered the best.

The Qi standard was developed by the Wireless Power Consortium and currently has over 200 million devices adhering to it across the world.

Other versions in use include the AirFuel Alliance, which combines the A4WP & PMA standard as well as the lesser known, and largely obsolete, Magne Charge.

For the most part you’ll be after a Qi certified charger as all mobile phone manufacturers have adopted the standard with the likes of Ikea now incorporating it into their furniture.

How long does it take to charge my phone wirelessly?

The short answer is longer. Around 25%-30% longer but your mileage will vary depending on the wattage the wall and wireless chargers you’re comparing can pump out.

If you’re after comprehensive stats the great folks over at MacRumors.com did an extensive comparison of wall & wireless chargers for the original iPhone X a couple of years ago that still rings true.

In general though, the numbers have improved and have improved from more than being an average of 50% slower a few years ago.

Wireless charging just simply isn’t as efficient as charging as using a cable is, but then again it’s not as futuristic that way now is it?

Are all wireless chargers the same?

Just like the mine-field that is trying to buy the right wall charger for a laptop or a phone these days, wireless chargers come in different varieties and can greatly affect your experience in using them.

Thankfully it’s not quite as bad with Qi chargers coming in either 5W, 7.5W & 10W models. They’ll all charge your Qi compatible device however if it supports the faster 7.5W or 10W standards then your device will naturally charge a little faster.

Be aware though, the more power the charger supports the heat it generates, which is something that can alarm wireless newcomers but is ultimately normal.

Can I wirelessly charge my phone?

Did you buy it in the last 18 months and spend more than A$700 on it? Then probably.

Most of the major mobile phone manufacturers have adopted wireless charging in their flagship models at the very least.

Apple, Samsung, Google, Huawei, LG, hell even Blackberry – all offer wireless charging in some shape or form.

You can also adapt most older phones by putting them into a wireless charging case that includes the wireless charging coil and connects to the phones USB or equivalent charger port.

 

Is wireless charging good for my phone’s battery?

There’s conflicting thoughts over this one but with wireless charging now well-adopted there’s been no major differences between wireless and wired charging in terms of battery degradation despite misleading reports.

Batteries will always degrade as they’re repeatedly charged. Each battery and mobile manufacturer have different standards but to give you an idea Apple published theirs which aims for 500 charge cycles over 2 years to retain an 80% capacity within the battery.

It’s commonly accepted that in order to maximise your battery’s life it should NOT be charged it to its full capacity. This is the same regardless of wether you’re using a cable or not.

In fact, the best way to keep your battery happy is to keep topping it up throughout the day, not letting it dip below 50% and never hitting 100%. Wireless chargers that you have at home and work might make this an easier feat to achieve, which in turn means it could in fact be better for your battery long term.

Do wireless chargers use more power?

Wireless chargers, like a TV in standby mode, do draw a current whilst not in use, but it’s basically nothing and hardly costing you buckets of cash. All chargers, wireless or not, draw power when they’re not charging their respective devices.

Newer versions of the Qi standard make use of NFC to activate the base when a device is present. This can lower the charger’s power draw and is said to draw less than 0.1mW when not in use.

 

Which charger should I buy?

In all honesty it mostly comes down to personal preference. Some are round, some have special padded matts some incorporate stands to charge your smart watch on also. There’s no steadfast rule about which is better beyond the having the maximum amount of wattage that your device supports for the fastest charging.

One of my favourites, is also one of the cheapest. Anker’s 10W Wireless Charging Pad is just A$24. It’s stylish, cheap and from a brand I trust. Nomad’s Wireless Charging Hub is another favourite, but at A$200 it will likely appeal to those far more aesthetically conscious. It includes an Apple Watch charging as well as having 3 7.5W coils hidden under a padded leather base.