A Much Larger Battery

Apple claimed no decrease in battery life for the new iPad compared to last year's model and only a 1 hour drop over LTE. The problem is that the combination of A5X SoC under GPU load, the LTE baseband and driving/lighting all of those pixels in the Retina Display has a significant impact on power consumption.

Apple addressed the issue by increasing the new iPad's battery capacity by 70%. If the leaked PCB photos are accurate (they look to be), Apple increased battery volume by shrinking the motherboard size and increasing the thickness of the tablet.

The new 42.5Wh battery is downright huge. To put the new iPad's battery in perspective, this is nearly the same battery capacity as the what was shipping in the 2008 13-inch MacBook Pro. This is also a bigger battery than what's used in the 2011 11-inch MacBook Air:

Apple Battery Capacity Comparison

Over the next two years you can expect to see the line between ultraportable and tablet blur considerably. Looking at where the new iPad falls in the chart above really begins to exemplify just how blurry that line is going to become.

With the display off, the new iPad looks and feels a lot like the iPad 2. The additional thickness is hard to see, but the additional weight is definitely noticeable. The new iPad isn't as heavy as the original model, but it's clearly heavier than the iPad 2. I don't believe the added weight is a deal breaker, but it is a step backwards. Maintaining battery life however obviously trumps added weight.

The math is pretty simple. If Apple is claiming 10 hours of battery life with a 42.5Wh battery, the new iPad with the iPad 2's battery would likely be good for just under 6 hours. Such a drop would be unacceptable and thus the new iPad gets a bigger battery and incurs additional weight from the new battery and display components.

The CPU & More Final Words


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  • cootang2 - Sunday, March 11, 2012 - link

    display technology and apple?? this display designed, developed, manufactured from other company. What apple did for this display is buying. Reply
  • stsk - Monday, March 12, 2012 - link

    And what "company" would that be? Please educate yourself about how contracted manufacturing works before proclaiming your ignorance. If Foxconn assembles for a variety of different manufacturers, none of which have similar design, does that make them all Foxconn devices? No, it doesn't. Most observers believe at least 3 separate manufacturers make displays for the new iPad. (and one of which apparently couldn't successfully get sufficient yield from emerging technology to stay in the game.) Apple designed the device, spec'd the parts, contracted the assembly. If you can find another product with a similar display, buy it. Otherwise, STFU. Reply
  • ZeDestructor - Friday, March 09, 2012 - link

    Page 2 (CPU) "768MB would imply 512MB on one channel and 128MB on the other, delivering peak performance for apps and data in the first 512MB but lower performance for the upper 128MB"

    512MB + 128MB = 640MB. I think you meant to put in 256MB.
  • JarredWalton - Friday, March 09, 2012 - link

    Fixed, thanks -- saw that as well when I was reading. :) Reply
  • quiksilvr - Friday, March 09, 2012 - link

    Anothing thing worth mentioning is that those Tegra 3 numbers come from a lower end Tegra 3 on HONEYCOMB and not ICE CREAM SANDWICH. So please make sure when the eventual battle occurs between the Asus Transformer Infinity 700 and iPad 3 that this is addressed. Reply
  • jjj - Friday, March 09, 2012 - link

    I would rather see a tablet with a sane screen and such a large battery ,would be way more useful.
    There is no reason to use this SoC in the next iPhone,would be pointless to add such a GPU and the vanilla A5 would be a better fit, so chances are we'll see a new one .
    The biggest drain on the battery should be the display's LEDs since it likely requires 2x also the extra bulk could be due to the screen being thicker,there was a lot of space to fit a bigger battery so i doubt the battery is thicker.

    In the first table for the new ipad baseband you added the CPU/GPU instead of the Qualcomm chip used.
  • ZeDestructor - Friday, March 09, 2012 - link

    Not any more than the iPad or iPad 2. Anand is correct here to talk about LTE. Radios do consume a fair bit of power when stressed. Especially with regards to data. Reply
  • jjj - Friday, March 09, 2012 - link

    nm about the first table supposed error,i guess for some reason that row is for the LTE model SoC not the baseband. Reply
  • Snowshredder102 - Friday, March 09, 2012 - link

    I tend to disagree, if you're going to be spending hours looking at something it better look good. The resolution is incredible just being a tad bit under the iPhones PPI. Insane battery life on these tablets aren't an issue with Apple, the battery life is already pretty good. Most people spend time around areas where they have access to a charger being at work, in their car, at home. I think the performance increase far outweighs a larger battery. Reply
  • zanon - Friday, March 09, 2012 - link

    Thanks for the summary, it was thorough and covers everything that can be done until physical units are available for tear-down and benchmarking. It sounds like the iPad 3 is a good example of practicality in engineering. As you say, Apple has put a great deal of emphasis on a few key user-facing elements, but was willing to make a few sacrifices against the optimal in places in order to hit reasonable volume, price, and timelines. Or in other words, "Real artists ship". It would be nice if full 28nm for all chips, A15/A7 big.LITTLE and so on were ready now, but that's the tech world I guess, always something new just on the horizon. Have to draw the line somewhere.

    Apple does seem to be falling behind a bit in iOS UI paradigms. Beyond side-loading, I continue to think that the single biggest core flaw/missing feature in iOS is a replacement for the file system, a new and updated data interaction and interchange UI. So far rather then address that Apple has just gone with "nothing", and other attempts seem to just be giving up and using the traditional filesystem in one form or another, but there's a big opportunity there to push things forward and it's key to actually making these devices real computer replacements IMO.

    Thanks again for this. I only had one minor quibble:
    >"The only downside is supply of these greater-than-HD panels is apparently very limited as a result of Apple buying up most of the production from as many as three different panel vendors."
    I think that's only a downside if the panels would have been available at the same time anyway. Often though Apple has gotten these deals by effectively fronting part or all of the immense amount of capital needed to get new factories and manufacturing lines online, which effectively brings forward when the stuff can get produced in volume anyway. Relatively quickly (6-12 months seems to be common) production will ramp up and exclusivity will expire, and everyone will have it all. Doesn't seem any different then if no one had accelerated things in the first place, except that a few get it earlier.

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