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Battery takes forever to charge

I noticed yesterday that having it plugged into my iMac was taking it forever to charge. I guess I'll plug it into a wall socket and see if that makes a difference.
 
JacaByte said:
Theoretically it should take 4 hours and 15 minutes to charge a new iPad from 0% with a 10 watt charger. (42.5WHr/10W = 4.25 Hr) If you charge it from a USB port on a Mac made after 2007 it'll take almost twice as long. (Max power provided by USB: 5.5W. 42.5WHr/5.5W = 7.73 Hr) Note that this process will take much longer if the iPad is on, whether you're charging from the wall or a USB port. (Given that the iPad is rated to run for 10 hours on its 42.5WHr battery it consumes 4.25 W of energy each hour!)

So what's probably going on is that the batteries that the new iPad comes with haven't been calibrated and are going on the fritz since the battery charging controller doesn't think the batteries have been charged when they have, in fact, been charged.

Apple doesn't provide any instruction on how to calibrate an iPad battery, but they do state here that it's a good idea to charge the battery to 100% and then completely drain it once a month. I would charge it until the charge percentage doesn't seem to be changing anymore, then I would drain the battery completely, then see if the iPad recharges to 100%.
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This is true in theory but battery capacitance doesn't work linearly, it's an exponential curved with a saturation point which is why it's the hardest to charge the last 90%
 
My new iPad was at 34% when I put on to charge at 7 am and was at 99% at 10:45 am. I used the 10 watt wall charger.

Seemed to take a little longer than my iPad 2 did but not as bad as others are reporting.
 
Judging by the charging curves that Apple uses it probably takes 3 and a half to 4 hours to charge to 80% from 0%, then 3 and a half to 4 more hours for the remaining 20%.The trickle charge from 80% to 100% could take less time though, but this seems like a more reasonable guesstimate to me. Once I have my iPad 3 I'll do some battery charging tests.

This battery is nearly as big as the one that Apple puts in its 17" Macbook Pros, I'm very surprised that they didn't provide a better means of charging the battery than with a 10 watt charger.
 
I let it charge overnight and did not experience any issues. If you're charging your iPad turn off data and switch to wifi and do not use your device .
 
Rgladman said:
My new iPad was at 34% when I put on to charge at 7 am and was at 99% at 10:45 am. I used the 10 watt wall charger.

Seemed to take a little longer than my iPad 2 did but not as bad as others are reporting.
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It is mostly the "sheep" going into a panic. Yes it will take longer to charge somyoumwillmhave to be responsible and remember to put your pad on the charger before you go to bed. 😛
 
MultiMediaWill said:
Why does my new iPad take forever to charge? It has been on the provided apple wall charger all day and still not at 100%. If the iPad is gonna take 24 hours to fully charge then I don't want it. Anyone else having this issue?
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You want the dense screen and quad core GPU needed to power it? Live with the huge battery that's necessary and longer charge times. It's a trade-off.

My Toshiba Thrive can charge in just over an hour, but then I have to carry around a laptop 19v/1.6a charger to do it. 😉
 
jessica. said:
I believe the voltages are different. That is what I meant.
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It's the same voltage.

The iPad chargers have always been 10w. Actually, they are 10.71w as they are 5.1v and 2.1a--even the one that came with the iPad 1.

The only thing different here is the capacity of the battery. Even the energy density is about the same as the iPad 2's. It's just physically much larger hence has a correspondingly larger capacity.



Michael

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seadragon said:
Important note!

Be sure to check the Amp rating on the charger too. I had a couple of 10 Watt apple chargers from the past but they are only 1.0 amp.
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You couldn't have had a 10w charger that was only 1 amp--5v at 1a is only 5 w. You mostly likely had the standard iPhone/iPod 5w charger that is 1 amp.




Michael
 
Redrum509 said:
Anyone think apple will release a new charger?
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That would be stupid when the iPad will only draw up to 2.1 amps anyway--the exact amount that the existing iPad 10w charger puts out.

Conversely I could say there already is a new charger for the iPhone: the iPad charger! Only problem is it won't charge an iPhone faster than an iPhone charger as the iPhone only draws about 1 amp max.




Michael
 
Using the 10w wall charger mine gets up to full capacity in just a little more time than my iPad 2. Maybe half an hour to forty five minutes longer. No big deal.
 
Stealthipad said:
No that is not right. What charger are you using. Some are using their iPhone charger and that will not work well.

If you are using the charger that came with it and it did not charge your iPad over night, return it.
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Thanks. I was using the charger that came with the iPad. (I don't have an iPhone. 🙂 ).

I'll try again tonight & if it doesn't charge fully, I'll exchange it. 🙁
 
Surf Monkey said:
Using the 10w wall charger mine gets up to full capacity in just a little more time than my iPad 2. Maybe half an hour to forty five minutes longer. No big deal.
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How long total? Its been 2 hours charging through macbook and battery is up 13%...
 
The iPad 3 definitely takes longer to charge than the 2. I believe it took mine about 5 hours last night. Now keep in mind all Apple devices are supposed to charge quicker from 0 to 80% than they do for 80 to 100%. LiPo batteries just have to be charged slower at the end.

I haven't timed it so I don't know how this one does. We all need to put our iPads through a few charge cycles then someone needs to do a more scientific test afterwards.

One thing that may help all of us is reducing the power load while charging. That could include turning off the LTE radio or even cellular altogether, and of course making sure the iPad is asleep.
 
If your new car has 2x larger tank, it's going to take 2x longer to fill..

The new iPad has a little less than 2x larger battery. It's going to take about that much longer to charge with the same capacity charger.

No big mystery. You want more features, you live with reality.

The new iPad is a great tablet. Enjoy it and just charge it accordingly.
 
Tinmania said:
That would be stupid when the iPad will only draw up to 2.1 amps anyway--the exact amount that the existing iPad 10w charger puts out.

Conversely I could say there already is a new charger for the iPhone: the iPad charger! Only problem is it won't charge an iPhone faster than an iPhone charger as the iPhone only draws about 1 amp max.




Michael
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Oh ok. I had no idea.
 
I went from 20% to 67% in about 2.5 hours using the included wall charger.

It arrived at 75% charge and went down to 25% after really heavy use. I'm quite happy. Like another poster has stated, just charge at night.
 
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