You've probably heard of quick charging, turbo charging, adaptive fast charging, rapid charging, and Qualcomm Quick Charge 2.0 before - or at least one or two of these things. What you may not know is that all of them are actually basically the same thing, based on the same licensed technology from Qualcomm known as Quick Charge.
With that basic premise in mind, what I want to dispel in this article is the notion that you need an OEM-branded charger to get the maximum charging speed out of your smartphone, because this generally isn't true. And understanding that could save you a fair bit of money, especially if your phone doesn't come with a quick charger, or you need a second one for work or travel.
First, let's talk about what Qualcomm's Quick Charge is. The basic thing you need to know is that "Quick Charge" is just a marketing term for the capabilities of the power management circuitry in your smartphone and wall charger. That means both your phone and your charger need to support quick charging in order for it to work. And no, that does not mean your phone needs a Qualcomm processor - quick charge support in end devices is contingent on only the power controller, not the larger chipset. Qualcomm has licensed the technology to non-Qualcomm smartphones like the Galaxy S6 (Exynos) and ZenFone 2 (Intel).
As far as how it works, quick charging allows you to dump a lot of power into your battery by using higher-than-normal voltage until it reaches what's called "saturation" - usually around 60-80% charge depending on how the phone's power management is configured. At that point, the phone's power controller scales back the amount of power it's receiving and your phone will begin to charge more and more slowly as it approaches 100%. This is where the "adaptive" language comes from in Samsung's fast charge marketing - quick charging allows your phone to intelligently scale the amount of power it takes from the charger based on the current charge state of the battery.
So, how do you know if your phone supports quick charging? You'll need to do some research on the web. You're going to have to consult Qualcomm's Quick Charge website or your device manufacturer if you want to know for sure without actually trying a quick charger. There are lists of phones with this technology out there - Qualcomm has a very good one that you can find right here - so if you're not sure, just do a little digging - it shouldn't be difficult information to find. Just remember that Quick Charge 2.0, quick charging, fast charging, adaptive fast charging, and turbo charging - they're all usually going to be referring to the same thing.
Now, by usually, I mean that there are essentially two generations of quick charging out there. You have the Qualcomm Quick Charge 1.0 devices, most of which came out in 2013 and early 2014 - phones like the Galaxy S5, Note 3, the first-gen Moto X, the Nexus 5, and a handful of others. These phones don't charge as quickly as Quick Charge 2.0 devices, but they should charge at full Quick Charge 1.0 speeds when using a Quick Charge 2.0 charger, so there's at least backwards compatibility.
Quick Charge 1.0 isn't on many new phones anymore, so it's not really as relevant to discuss - what you need to know is basically just that Quick Charge 1.0 isn't as fast as Quick Charge 2.0. How much slower is it? Qualcomm says it's around half the speed of Quick Charge 2.0 if you're charging from 0% for 30 minutes on a device that's turned off. It's worth noting, though, that the difference is probably proportionally less if you were to do, say, a 50 to 100% charge, because of the saturation effect and intelligent scaling.
Quick Charge 2.0 is the technology you see on the Galaxy S6, S6 Edge, the LG G4, the One M8, M9, the Note 4 and Note Edge, the ASUS ZenFone 2, the Moto X 2014, the Nexus 6, the DROID Turbo, and the list goes on and on. Like I said, check out the document Qualcomm has (here) if you want a complete listing of supported devices, because there are quite a few.
All of these phones, when using a Quick Charge 2.0 charger, are going to charge at basically the same speed relative to the rated capacity of their batteries. It shouldn't matter what brand the charger is - if it's a Qualcomm Quick Charge 2.0 certified charger, it's going to work and charge at the full rated speed a modern phone will allow. It's possible in the future faster chargers will emerge (ie, >18 watts), but for now, most phones only support 15 watts at maximum.
So, yes, you can charge your Motorola Nexus 6 with a Samsung Galaxy S6 Adaptive Fast Charger and still get basically the same charging speed as you would with the Motorola Turbo Charger 2.0 that the Nexus 6 comes with. And that, of course, brings us to an important question: why call them different things if they're all really the same?
Yes, your Nexus 6 will charge just as quick with a Samsung unit.
The answer, and there really is not much more to it than this, is marketing. Motorola would like you to buy their charger from them, and Samsung would you like you to buy their charger from them. That's pretty much it. Now, we can talk about whose charger contains higher-quality components and whose has a higher failure rate, but those things aren't relevant to the actual performance of the chargers themselves.
This is my point: you don't need an expensive, OEM-branded quick charger to get the maximum charging speed out of your phone. Qualcomm's own Quick Charge 2.0 documentation even has a list of Quick Charge 2.0-certified chargers (granted, it's far from complete).
This Aukey charger is around sixteen bucks on Amazon.
Why, then, does a Motorola Turbo Charger cost $35 while something like this Aukey Quick Charge 2.0 charger is just $16 on Amazon? Certainly, you could probably argue that the Motorola charger is subject to more scrutinizing quality control, potentially contains superior electrical components - and I cannot stress enough that even this may not be true, I haven't torn these chargers apart - and as such may have a lower failure rate than an off-brand charger. Beyond that? They're basically the same thing. (For the record, I tested the Aukey I bought on a Nexus 6, Galaxy S6, Galaxy Note 4, Note Edge, ASUS ZenFone 2, HTC One M8, M9, and LG G4 - all of them recognized it as a fast charger.)
Can the extra money for the official charger be justified, then? Let me put it this way, even if you bought two of these Aukeys - a brand which I am not specifically endorsing, it's just a random one I picked up on Amazon - and a month later one of them failed, you'd still come out ahead versus the OEM-branded charger. Here's a list of ones with at least 15W of output that seem to review well on Amazon, and there are likely even more well-reviewed ones out there on other online shopping sites.
- Anker 18W Quick Charge 2.0 wall charger
- Aukey 18W Quick Charge 2.0 wall charger
- CHOETECH 18W Quick Charge 2.0 wall charger
- Keedox 18W Quick Charge 2.0 wall charger
- iVoler 18W Quick Charge 2.0 wall charger
While I'm certainly not deaf to the argument that shoddy electronics exist, we've also got to realize that hundreds upon hundreds of companies are now building smartphone wall chargers, and there are only so many things you can really screw up before your Amazon reviews end up in the gutter. And remember, you're only going to need this charger, probably, for a couple years - does it really matter if the Motorola one is more likely to last for five? Let's also not forget that with the transition to Type C USB connectors on the horizon, full-sized USB ports on wall chargers may become a thing of the past within the next few years.
Another practical question about quick charging that you might have: how can I tell if the charger that came with my phone is a quick charger? This is actually easier than you might think. Among the various certifications and product info on the charger, you should find something resembling the word "output" - and next to that word you should see a voltage and an amperage, if not usually two or more voltages and amperages. Quick Charge 2.0 chargers generally have at least two ratings, one of which should be 15W or more (multiply the voltage by amperage to get your wattage - in this example its 1.67x9, which is roughly 15W).
You can see this Galaxy S6 / Note 4 charger has a peak output of approximately 15W
You'll find some that claim to be 18 watts (like all of the Amazon models I linked), or 12V at 1.5A and 9V at 2A, but as far as I can tell, no smartphone actually supports that amount of power yet, as no major smartphone manufacturer is shipping an 18-watt charger. But if your charger does support up to 18 watts, in theory you could be a little more future-proofed when phones with this charging speed start to come out. There are even 20 and 30W examples on Amazon, but again, no phone can take that much power just yet, and the end device will only accept the maximum level it's capable of handling, which for now appears to top out around 15W.
As to the whole 60W claim Qualcomm makes, well, that's really just theoretical - I don't think there even is a single-port 60W Quick Charge 2.0 charger yet, and 60W is a lot of power - more than enough even for many laptops. No smartphone is remotely close to supporting that amount of power input yet, so don't worry: 15 watts is generally the maximum these phones can accept, at least for now.
I hope this article's given you a little more insight on quick charging, how it works, and how you can save some money on your next charger - I know it was a learning experience for me simply in writing it.
Update: As suggested by one of our commenters, if you're looking for a good USB cable to go along with your quick charger, Monoprice has 24AWG microUSB cables that should handle all that current with no problem.