Apple's iPhone 6 and 6 Plus ship with higher capacity batteries that deliver exceptional battery life, but as pointed out by iLounge and MacRumors forum members, the two new iPhone models can also charge significantly faster when used with an iPad charging adapter rather than the smaller adapter included with the iPhones.

iphone6-charging
According to preliminary tests using a Kill-A-Watt device and OS X system information, the charging profile for the iPhone 6 and the 6 Plus match that of the iPad, allowing them to charge using 2.1A. Unlike earlier iPhone models which would only draw 5W regardless of the charger being used, the new phones are capable of drawing up to 12W, allowing them to charge at a faster rate. Early feedback from owners suggest the larger iPhone 6 Plus can charge fully in approximately two hours from an iPad adapter.

iphone6-chargingB

iPhone 5s (l) versus iPhone 6 Plus (r) charging profiles in OS X system report

The iPhone 6 and 6 Plus include the standard square 1A/5W charging block that shipped with previous iPhone models. To obtain these faster charging rates, iPhone 6 and 6 Plus owners may use the 2.1A/12W charger from the iPad or the high-power USB port of a newer model Mac.

Related Forum: iPhone

Top Rated Comments

BigBeast Avatar
144 months ago
It maybe safe, but it is not good for the battery to do this. I swear the quality of MR reporting his hitting rock bottom recently. I mean is this article for real?

Any device will charge quicker if you pump up the amps. Likewise it will charge slower if you use less amps. I don't recommend anyone does this regularly.
Actually, it is fine to do this. Apple officially supports using the 12W adapter for iPod 4th gen. and newer, and all iPhone and iPad models. On the flip side, charging your iPad with a charger that supplies less current that what it needs will damage your device.

I swear the contempt of MR readers sure has skyrocketed recently. I mean, are these people for real? :rolleyes:
Score: 31 Votes (Like | Disagree)
fivedots Avatar
144 months ago
Before anybody says it: Yes, it is safe. The phone draws the power and only the power it needs, not the other way around. They are intentionally designed this way.
Score: 30 Votes (Like | Disagree)
fivedots Avatar
144 months ago
It was designed for that amperage.

Makes no sense.

The charging circuit controls how much it wishes to draw. The charger does not decide how much to push.

The iPhone is entirely in control of how much juice it pulls, thus it is also clearly designed this way. Unless you're claiming to know something that the engineers who designed the thing don't.
Score: 26 Votes (Like | Disagree)
fivedots Avatar
144 months ago
don't be stupid, your iPad battery is designed for that specific amperage. The iPhone is not - ask yourself this. If it was good for the iPhone battery to take higher amps would Apple not give you a higher amp charger?

I mean:

1. They could standardise to a single charger for all products.
2. Happy customers because their phones charge super fast.

Common sense people!
Because the higher amperage charger is much larger and less convenient than the one included with the iPad?

This isn't an accident: the iPhone 6(+) circuit is intentionally designed to draw more amps. If they didn't want it to work this way, it wouldn't do it. The iPhone 5(S) do not work this way.
Score: 22 Votes (Like | Disagree)
Nozuka Avatar
144 months ago
it even says on the website, that you can use this charger.

http://store.apple.com/us/product/MD836LL/A/apple-12w-usb-power-adapter?fnode=3c
Score: 21 Votes (Like | Disagree)
SirOmega Avatar
144 months ago
Charging with more powerful adapters is hard on the li-ion battery. While it will give you a quick charge it will take a major toll on the batter life after a few months. There are hundreds of articles/videos on why this is so.

It maybe safe, but it is not good for the battery to do this. I swear the quality of MR reporting his hitting rock bottom recently. I mean is this article for real?

Any device will charge quicker if you pump up the amps. Likewise it will charge slower if you use less amps. I don't recommend anyone does this regularly.

So you're saying that my iPad battery is doomed?

Ya, I'd be concerned about the ramifications on the battery and long term performance. If this was the case, why wouldn't Apple just have included the more powerful charger?

Its clear no one here understands Li-Ion battery chemistry. I've been following this stuff for a while now for EVs (http://sequence-omega.net/?cat=4) (I drive a Volt).

A Li-Ion battery's usable life is determined by three variables - calendar life, cycle life, and charging rate (measured in "C" which is the ratio between charging rate and battery capacity in mAh - so "1C" is discharging or recharging the battery in 1 hour, 0.5 is two hours, and 2C is 30 minutes).

Recent research from Stanford Univ. (http://cleantechnica.com/2014/09/19/recharging-lithium-ion-batteries-rapidly-harmful/) has shown the effects of "slow charging" to be overstated, and the effects of fast-charging less harmful than originally thought.

Recharging an iPhone 5S at 1A is about .63C (1000mA / 1570mAh). Recharging an iPhone 6 Plus at 2.1A is .71C (2100mA / 2950mA). The difference there is not enough to dramatically effect the lifespan of the battery cell. The 6 has a higher charge rate of 1.16C, but I don't beleive that its very harmful to the battery and the higher charge rate will not shorten the overall lifespan of the battery. For reference, recharging an iPad Air at 2.1A is .24C ( 2100mA / 8820mAh).

Its not until you go over 2C that you start to see substantial impacts. Even Tesla owners who fast-charge frequently still have 99% original battery capacity after more than 100 cycles (http://gas2.org/2014/06/16/video-28000-miles-tesla-model-s-still-99-range/).
Score: 18 Votes (Like | Disagree)

Popular Stories

iPhone 17 Pro and Air Feature

Two iPhone 17 Pro and iPhone Air Colors Appear to Scratch More Easily

Friday September 19, 2025 10:02 am PDT by
As reported by Bloomberg today, some of the new iPhone 17 Pro and iPhone Air models on display at Apple Stores today are already scratched and scuffed. French blog Consomac also reported on this topic. The scratches appear to be most prominent on models with darker finishes, including the iPhone 17 Pro and Pro Max in Deep Blue, and the iPhone Air in Space Black. Images Credit: Consoma ...
Apple Foldable Thumb

Foldable iPhone Like 'Two Titanium iPhone Airs' Joined at the Hinge

Monday September 22, 2025 2:16 am PDT by
Next year's rumored foldable iPhone will showcase an ultra-thin design resembling "two titanium iPhone Airs side-by-side," according to Bloomberg's Mark Gurman. Writing in the Q&A section of his latest Power On newsletter, Gurman says Apple's first foldable device will be "super thin and a design achievement," combining Apple's thinnest iPhone form factor with cutting-edge folding...
iOS 26

iOS 26.0.1 Coming Soon, Likely With iPhone Air and iPhone 17 Pro Fix

Thursday September 18, 2025 9:17 am PDT by
Apple is preparing to release iOS 26.0.1, according to a private account on X with a proven track record of sharing information about future iOS versions. The update will have a build number of 23A350, or similar, the account said. It is likely that iOS 26.0.1 will fix a camera-related bug on the new iPhone Air and iPhone 17 Pro models. In his iPhone Air review, CNN Underscored's Henry T. ...
iPhone 17 Pro Colors

iPhone 17 Pro Max Teardown Reveals Qualcomm's Snapdragon X80 Modem for 5G

Friday September 19, 2025 7:39 am PDT by
While the iPhone Air is equipped with Apple's custom C1X modem for cellular connectivity, all of the iPhone 17 models are outfitted with Qualcomm modems still. A teardown video shared on Chinese platform Bilibili today (via Reddit) appears to confirm the iPhone 17 Pro Max is equipped with Qualcomm's Snapdragon X80 modem in particular. The same modem is likely used in the iPhone 17 and iPhone ...
iphone 17 pro max techwoven

Here Are The Best Cases You Can Buy for Your New iPhone 17 and iPhone Air

Friday September 19, 2025 6:46 am PDT by
Apple's new iPhones launch today, and there are plenty of options to choose from when it comes to protecting your new device from drops and scratches. In this article, we're taking a look at some of the best options for iPhone 17, iPhone 17 Pro, and iPhone 17 Air cases, as well as a few charging accessories. Note: MacRumors is an affiliate partner with some of these vendors. When you click a...
iphone 17 pro inside

iPhone 17 Teardowns Confirm SIM and eSIM-Only Battery Capacities

Friday September 19, 2025 8:39 am PDT by
YouTube channel REWA Technology today shared an iPhone 17 Pro teardown video, offering a closer look inside the model with a SIM card tray. We are still waiting for repair website iFixit to share a more comprehensive teardown of the latest iPhone models, but this video provides a good look in the meantime. The device features various internal design changes, including larger rear camera...