New iPad's most revolutionary feature is its battery

New iPad's most revolutionary feature is its battery

Summary: Massive increase in battery capacity changes everything... again.


The iPad's most revolutionary feature isn't the 2048x1536 Retina display LCD panel, or the 4G LTE connectivity. It's something that you can't see.

It's the battery.

Apple's put a lot of cool, but power-hungry technology into the new iPad. That Retina display screen, the quad-core graphics processor and the LTE modem all put pressure on the battery, yet Apple has managed to keep the iPad's battery life at 10 hours.

How has Apple managed this?

While Apple has undoubted put more power efficient technology into its next-generation iPad --- for example, dropping the processor architecture down from 40nm to 28 nm would have resulted in quite a significant power saving --- the more dramatic improvement has been the battery itself.

Between the release of the iPad 2 last year and the announcement of the new iPad yesterday, Apple has nearly doubled the capacity of the battery, taking it from 25Wh to a massive 42Wh. Measured in milliamps this boosts the battery from 6944 mAh to a monstrous 11,666 mAh.

And it's clear that Apple had no choice if it wanted the new iPad to be the device that it is. Even with this massive bump in battery capacity, the device is still only rated as having a 10-hour battery life. Without this boost to the battery, the old power cells would have been lucky to keep the new iPad going for 6 hours. It's clear that Apple isn't interested in getting into a numbers war over battery life, but instead wants to add new features incrementally while keeping battery life at that 10-hour mark.

The obvious way to boost the battery's capacity would be to double the battery size, but given that the new iPad is only fractionally thicker and heavier than the iPad 2, it's highly unlikely that the battery is significantly bigger than the one in the iPad 2.

There's another issue with adding a bigger battery, and it's all down to weight distribution. You might not have noticed by the weight of the iPad is perfectly balanced in order to make holding the tablet as comfortable as possible.

Big battery cells not only add weight, but also require careful engineering to make sure they don't unbalance the device. Keeping the cells as small as possible and in the center of the device makes engineering the rest of the device easier.

All this points to something very significant. It suggests that Apple has managed to increase significantly the power density of the Li-ion cells that it uses. In an industry that has seemed stagnant for some time now, this is quite an achievement and goes to show that Apple's battery research labs and manufacturing plants have been hard at work. There's no doubt that we're going to be seeing the fruits of this labor in other Apple products soon.

However, Apple has pulled off this huge increase in battery capacity (I'm looking forward to the teardowns of the new iPad), it undoubtedly changes everything... again.

Image source: Apple.


Topics: Hardware, Apple, iPad, Mobility

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  • Changes nothing !

    "However, Apple has pulled off this huge increase in battery capacity (I???m looking forward to the teardowns of the new iPad), it undoubtedly changes everything??? again"

    Sorry, this changes nothing... IPAD is stuck in the iPhone era(2007), with dead icons and then nothing...

    Just wait for Win 8... and undoubtedly it changes everything...
    • Fanboi alert

      Rofl you sound like another mad fanboi. You guys have been predicting apples downfall for how long now.
      • No, I think that was Newton.

      • I Missed the Part

        I missed the part where he 'predicted Apple's downfall', care to point me to that?

        All he said was that the new Windows 8 tablets will be more revolutionary than the new iPad, that may or may not be true, only time will tell. He said nothing about Apple 'experiencing a downfall', you simply made that part up.
        Doctor Demento
    • OMG Good one!

      You had me for a moment (until you mentioned Win 8) 8)
  • Same battery life

    Not revolutionary. Period.

    Edit: Well, I just checked the battery specs:
    IPad 2: 25Wh
    New iPad: 42.5Wh
    And all you guys who click the "-" button think that is revolutionary? Great.
    • Deservedly so

      You're getting downrated because your comment is stupid. They've quadrupled the display pixels, gone to a quad-core GPU to drive all those pixels, kept the physical dimensions virtually identical, and all of that without reducing battery life. Look, if you can't appreciate what an engineering achievement that is, then walk quietly by. But there's no reason to tell the rest of us that you don't know chit from Shinola.
      Robert Hahn
      • And perhaps...

        you and many other fanbois here do not know evolution from revolution? I am not here to please the ignorant.

        Edit: Since you seem to struggle with certain basic concepts, let me clarify: The first iPad started a REVOLUTION. The latest iPad with its improved features, is simply an EVOLUTION.
      • The Proper Term

        is not 'revolution' but rather 'incremental improvements', there's nothing wrong with making incremental improvements, the problem is that Apple likes to go wild with ridiculously inflated hype every little thing.

        Honestly, Apple reminds me of Neil Patrick Harris' character on 'How I Met Your Mother', who loves to overuse the word 'legendary' to describe absolutely everything 'I just made a snowman in the park, it was legendary', except for Apple it's 'I just made a snowman in the park, it is the most revolutionary snowman ever designed!'
        Doctor Demento
      • I differ with your opinion, D.T. Long

        Technically, your correct - according to the letter of the law, so to speak.

        For example, one could say that Homo Sapiens currently roaming the plains of New York City are only an evolutionary advancement from Lucy's prodigy that roamed the ancient Serengeti plains of Africa.

        But saying mankind's current 21st century achievements are less than revolutionary compared to the tools Lucy used would be in error.

        Regarding the new iPad, the ability to see images in such high resolution on a display that HAS NEVER BEEN SEEN before is revolutionary in my opinion.

        Of course, you would argue that this display is only an evolutionary achievement when compared to the first black and white TV monitor of the early 1950's. And you would be right .. according to the letter of the law.

        I just don't view human achievements in such a narrowly defined manner that you do.
      • Dimensions and weight point to bigger battery, not complicated

        The thickness went from 8.8mm to 9.4mm and the weight from 1.3 to 1.5 LBS. That is .6mm more space across the whole of the device which is considerable in these types of devices. So is the weight increase of roughly 10%.
      • Who cares

        I don't care to get mixed up with the revolutionary vs evolutionary argument. Just is that the iPad HD is a great new release of a product line and it is obvious certain metrics must be met for The iPad which is 10 hour battery life.
      • Hold on...

        "They've quadrupled the display pixels, gone to a quad-core GPU to drive all those pixels, kept the physical dimensions virtually identical, and all of that without reducing battery life."

        Yes, by *using* a battery with 60% more capacity that's significantly LARGER than the previous battery.

        Which is what pretty much ANYONE does when they make a battery with a bigger capacity. How is this how a major engineering achievement?
      • Shoot man

        no points for what an engineering feat it was - bottom line is what use is it to the viever???? (Human factors, IOW)...... Sheesh
      • But you are miising a point

        This means the iPad is a lot less energy efficient - that extra battery capacity means more drain on energy sources for charging and more energy dissipation i.e its using nearly as twice as much power
        Not a good design for the planet!
        • Ipad cost less than a Starbucks coffe to charge for a year!

          The new iPad I should cost less than 3 dollars to your charge a year..... Cost less to run the new Ipad the a room of lights! So check it out
    • Think of a car

      I'm not an Apple fan, but it is revolutionary. If you increase the weight of a car without increasing the horsepower, the car will be sluggish. If you increase the number of cylinders to compensate, then you consume more gas. Apple was able to deliver more without affecting batter life; that IS impressive.
      • Missing it

        In this case, they went from a slim gas sipping vehicle to a full blown SUV with a bigger tank to allow you to travel the same distance.

        What I want to see is the reviews. One of the big complaints with the original iPad was weight. Apple gave us the slim trim iPad2. Now we are back to the same weight. Will we see the same complaints?
      • What?

        You just contradicted yourself. Apple did in fact increase the number of cylinders by putting in a bigger battery. It's why the new iPad is heavier and thicker. The battery isn't the same size as the previous iPad2. If it was I would agree with you. Actually, I've read a few reports now that say the new iPads were running hot to the touch after prolonged use at the presentation yesterday too. Cooler, more efficient? I don't think so.
      • We have to wait for the teardowns, but ...

        ... assuming the width & length of the iPad3 remains the same and that the thickness of the case remains the same. We can also assume that the motherboard and internal circuitry have shrunk a little. Let's also assume that the new battery consumes the additional volume provided by the thicker case:
        (0.94cm - 0.88cm) x (24.1cm x 18.6cm)
        = 0.06cm x 448.26cm^2
        = 26.9cm^3 of additional battery volume (approx).

        That's enough room for a fair amount of juice, especially if they've managed to reach the upper-end of LiOn battery tech today (2MJ/L).

        Combined with the die shrink and careful optimization of the display engine & codec's, there's little reason why the iPad3 can't run for around 10 hours, except if the user plays a CPU & GPU-intensive game for the duration, whereupon I'd expect the battery to run dry more quickly.

        Make no mistake though - this is just an evolution. It's Moore's law applied to screens & GPU's with the addition of a bigger battery.

        What's most disappointing to me is that the IOS UI has barely changed for some time now. A grid of static shiny-looking icons is already starting to look a little tired. But does Apple have the courage necessary to disrupt their cash-cow when it's delivering so much milk?