What is wireless charging? How does it work and will we soon be ditching our cables for good? Join us as we demystify the magic behind charging sans tangles…
Forget about forgetting your charger. Wireless charging technology is already a staple feature in many Android phones and, with rumours swirling about Apple’s plans for the iPhone 8, it may soon be the primary source of smartphone power everywhere. But what does this mean for you and your cables? Read on to find out more…
What is wireless charging?
The name is a bit of a give-away with this one: wireless charging allows you to charge your devices without the need for wires. That means no tangled cords and fiddly connections. Simply place your device on a charging pad (which is connected to a power source) and before long you’ll be recharged and ready to go.
How does it work?
Also known as inductive charging, wireless charging uses electromagnetic fields to safely transfer power from a transmitting source (i.e. a charging pad or station) to a receiving device (i.e. your phone). For charging to take place, both the charging pad and device must contain an induction coil – that’s why you can’t go plonking any old phone on a wireless pad.
The powered coil in the charging pad creates an electromagnetic field around itself, and then, when the second coil gets close enough, the power is automatically transferred via electromagnetism to your device’s battery. As a bonus, because these coils can be completely enclosed, they’re not subject to the same kind of wear and tear as regular chargers and sockets. That makes them ideal for wet environments like the bathroom. Got an electric toothbrush? Then you’ve already seen wireless charging in action.
Up until recently, wireless chargers have had a maximum output of 5 volts at 1 amp, which is a lot slower than your standard wall charger. All well and good if you want to pop your phone down on the charger overnight, or perhaps even on your desk while you work, but not really ideal if you’re in a hurry and need a rapid boost.
But the good news is: things are getting faster. Samsung’s Fast Wireless Charger is just one example of this, and when put to the test by the team over at Android Central in September last year it was found to cut the total time to wirelessly charge a Galaxy S7 (from 9% to 100%) from around five hours to just over two.
When did wireless charging come about?
While it’s only really come to the fore for smartphone owners in recent years, the concept of wireless charging is over a century old. Wireless power transfer can be tracked right back to 1891, when prolific inventor Nikola Tesla created the Tesla coil. In fact, all modern inductive charging is based on Tesla’s principle of electromagnetic induction. He even envisioned using the technology to beam electricity to entire towns from a massive central coil – something he sadly never got working.
How can I use it?
The most prominent wireless charging system at the moment is Qi (pronounced chee). It takes its name from the Chinese symbol meaning ‘energy flow’ and has been backed by over 200 manufacturers to-date – including Google, Samsung, Nokia and LG. As such, most wireless chargers use the Qi system, but it’s not the only wireless charging standard out there. The other major player in the wireless charging market is the Airfuel Alliance (formerly known as PMA). These guys made waves a few years ago when Starbucks announced it would incorporate the Airfuel Alliance’s Powermat wireless charging technology across all its stores in the United States.
Competition among companies is usually a good thing for us on the ground, but not so here; many commentators believe the lack of a single global standard for wireless charging has contributed to its relatively slow uptake. However, some manufacturers – like Samsung – are now embracing both.
The good news? Even if your phone or device doesn’t have in-built wireless charging, you can still get in on the action – you’ll just need a little help. There’s now a wide range of rear covers, cases and chargers on the market to help get your smartphone wireless ready.
What’s next for wireless charging?
Many of the arguments against wireless charging have typically stemmed from its speed (or lack thereof) compared to traditional cables, and the fact that your device must remain flat on the charging platform to charge. But engineers are continually exploring new ways to increase the efficiency and practicality of wireless charging, with some pretty cool results.
Recent advancements in resonant wireless charging have increased Qi’s charging range to around 4 centimetres, and in the near future we could feasibly see power safely transmitted across several metres. Wireless charging stations and accessories are already being incorporated into our cars, coffee shops and furniture, and it’s thought that in the future wall-sized charging stations might be able to transmit power to multiple devices in a room. And when we get there, you’ll be able to give your phone a constant charge simply by stepping into your home or office.
Until then, we’ll be keeping a watchful eye on wireless developments in the hopes that one day soon we can ditch all cords for good.
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