Battle of the iPhone inductive (wireless) Qi chargers
One of the big advantages of the Samsung Galaxy S6 and Note 5 is that they support inductive charging, which means you can simply sit your phone down on a special surface and it charges -- without needing to plug in a cable. But even though Apple doesn't provide inductive charging in the iPhones (why?), it turns out to be relatively easy and inexpensive to add on your own.
In this article, we're going to explore both how to add inductive charging to your iPhone and then look at four different chargers to compare performance.
To get started, I ordered the QIVV Qi Wireless Charging Receiver for $12.99 from Amazon. The way this works is you plug the Lightning connector on the receiver into your phone, wrap it around the back of the phone, and generally tape it down. You can see mine below.
There are a bunch of little known companies selling these receiver patches. They're incredibly thin, and it's difficult to tell if there is much of a difference between them. I went with the one that had a bunch of good reviews.
The best way to work with these patch receivers is to tuck them into a case, which is what I did.
I'm rocking the Urban Armor case below. I bought it after reading Matthew Miller's ZDNet review on a similar case for the Galaxy Note 5.
My old charging configuration
I've been using Qi inductive charging for a few years now. I first retrofitted my old iPhone 4s with with a Qi shell, and bought a bunch of Nokia chargers, which I scattered around the house. I then put a receiver similar to the one above inside the back of my Samsung Galaxy S4 and used that with the same Nokia chargers.
The reason I used Nokia chargers is back when I went inductive, some of the Nokia phones used inductive charging, and they sold a well-regarded inductive charger. Back then, they were also expensive, a good four or five times what a charger costs today.
Unfortunately, after installing the receiver in my iPhone 6s Plus, I discovered the Nokia chargers just weren't working all that well. I'd sometimes get a good charge, but rarely. Often, I'd leave my phone on the charger all night, to be greeted with a bunch of "boink" sounds when the phone would alternately register being on the charger and off the charger -- all while the phone was sitting, untouched, on the charger.
I thought seriously of just going back to the cable, but I don't like using two hands to put my phone on or off the charger. In bed, it's impossible to reach the cable without getting out of bed to use two hands. And in my work area, the charger is off to the side, where it's not easily reached by my left hand.
I also tried a few cable-based dock chargers, but much to my surprise, they were all so light that when you lifted the phone off them, the dock lifted as well. Worse, they tended to mount the phone on a lightning adapter that just rose above the charger, with no support for the phone. Overall, not optimal.
The three new contenders
So I decided to do more research into Qi chargers. One of my friends mentioned that he had used wireless charging, but his phone wound up overheating. That worried me, and I wanted to know more.
I did some reading and found out some Qi chargers use less power than others. Most of the current-generation chargers want 2 amp chargers. The old Nokia chargers use less than an amp. So, in addition to the chargers, I also bought some good 2 amp USB wall adapters. I've had good success with Anker products, so I bought a two-pack of their 2 amp chargers for about $12 (or six bucks each).
I next ordered three current-generation models with three different form factors. The entire package of goodies is shown in the picture below.
The first device I got was another Anker product, the Anker Ultra-Slim Wireless Charging Pad. It had more than 900 reviews with a 4-star rating and a reasonable $19.99 price tag:
One thing I noticed in my reading is that some chargers have more than one set of charging coils. My understanding is this approach makes the connection between the phone and the charger more reliable.
Since the old Nokia chargers had problems with connection, I decided to try two well-rated three-coil chargers. The first is simply a rectangular slab, the Choetech CHOE Stadium Qi Wireless Charging Pad, sold on Amazon for $25.99:
The third new charger I ordered was the DLAND T-310 Foldable Stand. What's nice about this one is it folds down flat, or stands up, allowing you to see your phone. Unfortunately, I found the stand-like nature of the cradle more annoying than not, mostly because where I had to place the stand on my desk meant the phone faced away from me. It's actually pretty cool if it fits your space. It's also $49.99, so it's the most expensive of the bunch.
Testing
Once I got the three, I decided to subject them to a set of tests, which were harder to do than I expected. While my Galaxy S4 would lose battery power if you merely used the phone, getting my iPhone 6s Plus to the point where it needs more power could take days.
In order to test the chargers with the iPhone, I fired up Netflix and ran a couple of movies, which got the phone down to between 60 and 70 percent. Yeah, you're looking at about four hours per test just to get the phone battery low enough. With eight test passes, we're talking 32 hours just to get the phone ready to test -- and that's not counting the charging time itself.
I put the phone on each charger for exactly one hour. Before the test, I measured the temperature of the phone externally using an infrared thermometer, pointing the laser sight at exactly the same spot each time. I also looked at the battery charge level. After each test, I did the same thing. I pointed the thermometer at the same spot, took a reading, and then recorded battery level.
I did this process twice for each phone, after making sure the phone's external temperature settled back down to around 75 degrees. The following table shows the results, which were not entirely conclusive.
| Test | Vendor | Form Factor | Battery Gain | Temp Gain |
|---|---|---|---|---|
| #1 | Anker | Round | 18% | 19 degrees |
| #2 | Anker | Round | 18% | 12 degrees |
| #1 | Choetech | Round Rect | 18% | 25 degrees |
| #2 | Choetech | Round Rect | 16% | 40 degrees |
| #1 | DLAND | Folding | 12% | 33 degrees |
| #2 | DLAND | Folding | 18% | 41 degrees |
| #1 | Nokia | Round Rect | 4% | 3 degrees |
| #2 | Nokia | Round Rect | 18% | 12 degrees |
As you can see, an hour's charge generally increased the phone's battery capacity around 18 percent. That means going from zero is about a five hour charge. The Nokia completed a full 18 percent increase once, but as I've noticed, it's not reliable. Another hour resulted in only a 4 percent improvement.
The folding DLAND device deviated from the 18 percent amount in its first run -- it did only a 12 percent improvement, but also gained 33 degrees. In its second run, it increased battery by the 18 percent common amount, but with a whopping 41 degree gain.
The rectangular CHOE was my favorite, because it never made any "boink" sounds, indicated an incomplete connection. It gained 18 percent battery in one run and 16 percent in another. But one run resulted in a substantial 40 degree temperature increase, while another run resulted in a 25 degree temperature increase.
The round Anker charger -- the least expensive of the bunch -- may be the winner, though. It gained exactly 18 percent charge in each run, and it caused the lowest temperature gain of any of the chargers, 12 degrees in one pass and 19 degrees in the next.
Bottom line
So, what's the bottom line? To be honest, I'm still not completely satisfied. I'm going to keep the Anker and return the others, but I'm also thinking about 3D printing a corded charging dock that's heavy enough to stay put when I pick up the phone.
Stay tuned. I'm sure I'll write about that project in future articles.
But is inductive charging the way to go? I am concerned about the temperature gain, and the phone often starts to do it's incredibly annoying "boink" sound when it reaches a full charge or loses connection. But it's definitely convenient.
What do you think? Do you use inductive charging on your iPhones (or other phones)? Do you have reliability or temperature issues. TalkBack below.
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