KPH tech blog

As well as upgrading my portable power bank, I thought about maybe getting myself a wireless charger. After all, they save on messy heaps of cables and adaptors, and are great accessories for your office desk or home.

They use the NFC chip on the rear of your phone, and provide a wireless charge via Near Field Communications (NFC). While the charger itself still has to be plugged in to a wall socket, there is no physical connection between it and your phone… hence the term wireless charger.

Although, I would just like to point out that this doesn’t technically mean wireless… since the charger still has to be plugged in. With a wire. And a plug.

The first wireless chargers were rated at 5 watts, whereas now many wireless chargers compatible with iPhone’s and Samsung Galaxy’s are rated at 7.5W and 10W.

Some of them have dual- or even triple-coil charging, offering faster charging speeds, and most of them support charging the phone both vertically (for using the phone while charging) and horizontally (to watch movies while charging).

Plus, some also offer all of this functionality even while the phone is covered with a case (although most chargers specify that your phone’s case has to be thinner than 5mm).

But, (and this is the real sticking point for me) most of them say ‘fast charging‘ at 10W but don’t specify the current or voltage. This info would be helpful in working out the charging speeds.

Generally speaking, the Voltage multiplied by the Amps gives you the Wattage. So for all the power banks I’d been researching, some offered 5V/3A (15W), and for my Galaxy S7 and S9 Plus, 9V/1.67A (also approx 15W).

Read around, and you’ll discover that wireless charging speeds aren’t great at the moment, and now I can understand why. For a wireless charger offering supposedly ‘fast charging’ at 10W, that puts the current at about 5V/2A. I’m currently used to charging my Galaxy S9 Plus in around 1.5hrs at 9V/2A, but a lower Voltage means the supposedly ‘fast charge’ time is more than the real fast charge time with the wired charger that came with the phone…

A wireless fast charge time of 2.5hrs never made any sense to me, but now it does. For a £25 wireless Qi charger, what the seller is not telling us (and perhaps, deliberately) is that a 10W fast charger isn’t as ‘fast’ as the delivery of power from a wired connection.

At the moment, the only way to get a real fast charge is via a wired connection to the wall socket. I’d love to invest in the wireless revolution, but considering the charger is still wired, that doesn’t immediately say wireless to me… especially when you consider the term ‘wireless‘ was first used to describe a radio that isn’t wired to the wall.

Wireless chargers just don’t offer any advantages to me over a wired connection – for starters, it’s not completely wireless, and secondly, I’m paying out more cash for something that charges my phone even slower than the wall charger I already have.

That said, the future is looking a little better now that Huawei has started the reverse wireless charging revolution, which Samsung have included in their Galaxy S10 lineup. Also, I’ve recently seen a couple of wireless chargers starting to offer the same speeds as traditional wired methods.

Maybe, in time, I’ll join the wireless crew. But for now, I’m sticking to wired charging.

– Chris JK.