iPad 3 slow charging with 10W charger?

Hey,

Although the new iPad is an amazing device, I have to admit the charging time is a bit of a pain sometimes. I'm trying to help out the community through gathering a list of charging tips. I posted them here: http://tech-hacks.net/tech/apple/103/how-to-charge-the-new-ipad-faster/ . Hope it will be of help to anyone that thinks the charging time it's a bit on the slow side 🙂

Have a great day 🙂

Edit: I will update the list as I gather more tips!

Edit: Added comment

On cables... The people who made the Minty Boost did some tests on chargers and found that even a few tenths of a volt difference on the USB DATA lines, yes data lines, will affect how fast Apple devices charge.

http://www.ladyada.net/make/mintyboost/icharge.html

It seems that various chargers float the data lines at slightly different voltages. The i-device in question checks this voltage to determine how much current it can draw. It's not as simple as slapping 5 volts to the USB power wire and a ground and the device will suck up as much power as the charger can output. There seems to be a method to Apple's madness.

So aftermarket cables, extra long cables, USB extention cables, all can affect charging rate because even a small amount of resistance can create a voltage drop. Even to the point of getting a message that "the power supply can not charge this device." or something to that effect when I inserted two high quality USB extension cables between the Apple charging cable and the charing electronics.

I got that message on an iPad 1 BTW. With one aftermarket cable the iPad 1 and an iPhone took overnight to charge.

Another thought...

I 'd like to try a 20w 5v power supply with an adjustable trim potentiometer on the data lines and an ammeter on the power lines to try and "dial in" the maximum charge rate possible. I wouldn't be surprised if Apple has a 15 or 20 amp charge rate mode for the iPad 3.

Kevin, I doubt that will work. Something interesting I found out is that the high-powered USB chargers built into Macs use proprietary signaling invented by IBM to boost the _voltage_, not the amperage. They bump up to 12V at 1200mA, for 14.4W, for cooler high speed charging. (Higher voltage means less resistance and more efficiency, but requires bulkier transformers from AC.) At that power, you could turn 6 hours of charge into 4.5 hours. The technology they use allows 1.5A sustained and another step up to 24V, which would bring charging times down to 2 hours if you could keep it cool enough while charging.

I'm not sure why they didn't provide 12V or 24V chargers with the new iPads; would they be too large or run too hot? Does it shorten battery life? Lots of questions but it's unlikely Apple will ever answer.

BTW, you need a lot of specialized circuitry to make the 12V work; just wiring 12V into a USB port will blow it up without the right communication, since it'll still expect 5V.

If the battery in the new iPad has 70% more capacity than the iPad 2, and presumably even more than the iPad 1, but takes considerably longer to charge (which has been my experience...my iPad 1 would charge in a few hrs, whereas my iPad 3 takes 8-10 hrs in sleep mode, and does not charge at all while actually using it, with the stock charger), I would expect the trade off to be considerably longer battery life on the iPad 3, which I could live with, but is not the case. If anything, the iPad 3 has a somewhat shorter battery life than the iPad 1, so Apple has essentially sacrificed charging time and battery life for a somewhat higher resolution display and and a few more gee-gaws. Seems like one small step and enormous profits for Apple, and one giant leap backwards for mankind, eh?

"somewhat better resolution"? 4x better qualifies as somewhat? Lmao. Double the processing power is a small step? lmao. How are you going to get all that improvement with a significantly longer battery life? Youre delusional! For your next car, you should demand that it gets 100 mpg, goes 200 mph, and costs $499...

I've noticed this after changing from an ipad 2 to a ipad 4,I was watching a movie on its first battery cycle so I was trying to drain it down"which I did" so I plugged the charger In using a 2m USB extension,it was then I realised this issue so I forgot the movie and timed the charge time from 0% to 100% which was around 12 hrs,second charge from 0% to 100% using just the lightning cable 5 hrs,third charge using a 1 metre USB extension plus the lightning cable took 8 hrs. So I can honestly say that using a USB extension which most people have to use because of the very short lightning cable makes a massive difference on the charge time! I've now started just plugging my pad in now to the charger(with 1 metre USB exstension)just to slow down the battery count a little lol,come on apple sort us a longer lightning cable with 0 voltage drop!!!!!!!

Sorry just realised my errors,mine is the ipad 4 with the new 12 watt charger so you guys with the three might like to try one of these instead,this would explain why my charge times are quicker.:)

Artfog, I agree that I unreasonably downplayed the improvements of the iPad 3 over the iPad 1, but my main point was the glacially slow charging time of the iPad 3, which has gotten worse over time. In other words, for a car that cost 40 grand, I would expect to be able to fill the gas tank in 5 or 10 minutes, not a half hour. This is a well documented problem with the iPad 3, and the charging power is so weak that it's difficult to charge at all if you're using it at the same time. For the most expensive tablet on the market with 64GB and 3G, having to wait 12 - 15 hrs for a full charge with the stock cable and charger is unacceptable. Would you be OK with that?

That's a reasonable expectation, but again where do you get 12-15 hours to charge? My iPad 3 take 8 hours or less for a full charge. I'm using the included 10w charger and included cable.

i have an ipad 1, but i have two bits of information that can be helpful

1) not all 10w chargers are created equal

http://gizmodo.com/5535631/the-fastest-and-slowest-way-to-charge-an-ipad

i have now purchased the griffin 10w charger, and i use a generic 10ft cable from monoprice. if it is really a hassle invessting $20 into a new charger can make a big difference. my ipad 1 chargers really quickly, even when on.

2) not all cables are created equal. i know companies make "charge only" micro usb cables that can charge a phone almost twice as fast. charge only cables combine the data with the ground, or something of the sorts. so obviously these cables cannot be used to transfer data. but when plugged into a usb charger who needs data?

i tried to find (google) a "charge only" apple cable, but only found some on ebay which i am not sure are really charge only.

Well, when I traveI I usually only take one charger for my iPhone and iPad. (have to take two cables because of Apple's iPhone5 connector change). I take the charger that came with my iPad. Bigger is better . . . .right?

I accidentally ran my iPhone out of battery. Plugged it into the iPad charger; it took all night long to get the iPhone5 charged. It actually took over an hour for the iPhone to just come alive. 9 hours later, it was only up to 89%.

It takes all day to charge the iPad with the big charger. So it's slow charging either device.

Ken

Check the bottom of the iPad charger to see how many watts it is u may need a magnifying glass it's pretty small if u have the 5 watt charger this would explain why it is charging slowly. My iPad 3 takes 6 hours to charge fully from 0%I usually do it overnight***

Yeah, mines says 10 watts. But I'd be surprised if it's doing ONE watt, the way it took all night to charge my iPhone to 89%. The tiny charger brings that iPhone to life from dead battery in just a few minutes . . . . fully charged pretty quickly. Charging off the computer is quick, too. If I remember correctly, charging the iPad off the computer takes forever, though.

Ken