How long does it take to charge a iPad 3 from 0 %

Here is some info I found on the subject from The Redmond Pie Site.

That's just another report regarding the same questionable analysis.

@ Philly_Phan I am not unwilling to accept Apple's explanation, in fact I agree with them - read my prev post :)

All I'm doing is discussing this guy's findings since they may have important implications if true. What he implies is that the new iPad's battery meter is wrongly calibrated and that the battery is not fully charged when it indicates 100%; which is why it continues charging until the battery is actually full. However on further reflection, I believe either this guy's measurements are suspect, or he has a defective iPad, because after the battery is 80% full the charging rate reduces drastically and the charger should certainly not draw 10W of power.

I hope someone else conducts an experiment to determine how much current the charger is drawing once the battery meter indicates 100% charge.

firoze wrote:

All I'm doing is discussing this guy's findings since they may have important implications if true.

And I maintain that his analysis is faulty.

I don't doubt the person, but I do doubt the methodology. Sounds like he plugged an iPad charger into a Kill-A-Watt, and that's not good enough for several reasons. You need to splice a voltmeter and ammeter of appropriate range into the charging cable or better yet, iPad battery leads.

The device's use of power does not decide the voltage but it does decide the current, hence, "draw". Volts x amps = watts, a unit of power. The only correct unit is watts. Yes, devices do draw watts. Well an English teacher might consider it colloquial, but no worse than "I drove 50 miles".

As alluded earlier, battery charging curves are complex. Most batteries charge fastest in the midrange, i.e. from 20-80% and they charge slower and slower as they approach 100%... "approach" like an asymptote. As you get past 90%, the time needed to gain another 1% charge is going up exponentially. The only way to get to 100% is to lie, and define a "paper 100%" at chemical 95% or thereabouts. Now you have a reasonable paper charge time, and a few percent of "bonus power" if charged beyond that. Charge efficiency also suffers horribly in that last few percent, mostly you're just heating the battery pack, which itself can be damaging to the pack. When do you throw in the towel and call it good? The product maker's job is to make those issues transparent to us.

So along comes some blogger, and measures a corner of these phenomena and leaps to conclusions.

Blogger leaps to conclusions, film at 11. 😝

The quickest way (and really the only way) to charge your iPad is with the included 10W USB Power Adapter. iPad will also charge, although more slowly, when attached to a computer with a high-power USB port (many recent Mac computers) or with an iPhone Power Adapter (5W). When attached to a computer via a standard USB port (most PCs or older Mac computers) iPad will charge very slowly (but iPad indicates not charging). Make sure your computer is on while charging iPad via USB. If iPad is connected to a computer that’s turned off or is in sleep or standby mode, the iPad battery will continue to drain.

Apple recommends that once a month you let the iPad fully discharge & then recharge to 100%.

At this link http://www.tomshardware.com/reviews/galaxy-tab-android-tablet,3014-11.html , tests show that the iPad 2 battery will charge to 90% in 3 hours 1 minute. It will charge to 100% in 4 hours 2 minutes. The new iPad has a larger capacity battery, so using the 10W charger will obviously take longer. If you are using your iPad while charging, it will take even longer. It's best to turn your new iPad OFF and charge over night.

 Cheers, Tom 😉

I like the idea of charging overnight. I am using a reguar outlet. What do you think of the IPad Dock. Any advantage? New Purchaser of IPad3.

Based on my personal experience with a complete depleted battery all the way down to 0% that it takes 7 hours to fully charge the device....hope this answers your inquiry.

Unfortunately, using a dock will not make any faster to charge the new iPad....I wish that apple comes up with a faster charger for this THING...but for the mean time, charging it at night is highly recommended and will do just fine...unless you sleep a lot less than 7 hours.

My iPad only got to 38% in 4 hours, it also displays not charging the whole time my iPad is charging. I also have the problem of my iPad stopping at 77 and 89% of charge sometimes.

And I'm using the 10w wall charger, not plugging my iPad into my computer or charging it via USB cable. Just the 10w wall charger.

I'm not all technical or anything... When mine says 100% I actually know it IS fully charged because the charger itself is no longer warm. Means it's done charging, because while it is actively charging the charger is pretty darn warm. And mine charged from about 17% to 100% in a little over 5 hours!! No kidding. And like I said, I know it was done because the charger wasn't warm anymore.

The solution for people with charging problems, once myself, it to get the 10w charger replaced. Now my ipad is charging in 4 hours as opposed to all day. Feels great to have a working ipad!!

I find that hard to believe.

According to the Tom's Hardware link posted by Texas Mac Man, it takes 4 hours to charge an iPad 2 from 0 to 100%.

According to you, your iPad 3, with a 70% larger battery than the iPad 2, using the same 2 amp charger as the iPad 2, also charges 0 to 100% in 4 hours.

What's your secret?

I find that claim to be a bit hard to believe myself, at least if we are talking about going from 0% up to a full 100% charge. My new iPad will charge fully in about 6 hours - if the battery is at or near 10% which I think is fine for new, larger battery. I am very pleased with the time that it takes to charge - and I might add that my iPad continues to charge while I am using it - if it is plugged into a power source with the supplied adapter.

Maybe the four hours is from 25 or 30 % of battery level and it is just not being stated explicitly.