Apple says 100% iPad recharge "problem" is by design

Apple says 100% iPad recharge "problem" is by design

Summary: After days of silence, Apple tells AllThingsD that the Apple iPad recharge "problem" is actually by design. Dr. Soneira, who found the problem, disagrees.


When is 100% charged not 100% charged? When it's an Apple iPad 3.

When is 100% charged not 100% charged? When it's Apple iPad 3.

To believe Apple about its iPad 3 battery problem or not to believe Apple is the question. In a story by Ina Fried at AllThingsD, Apple VP Michael Tchao explained that while the iPad--and iPhone and iPod Touch—display as 100% charged before the device is actually 100% charged, it's because they're constantly charging to 100 percent, and then discharging and recharging back up to 100 percent. The point, according to Apple, is to maintain the best possible charge. Dr. Raymond Soneira, president of DisplayMate, the world’s leading display and display tuning company, who found the battery problem in the first place disagrees.

While Tchao calls this “a great feature that’s always been in iOS,” Soneira doesn't see it that way. He sees it as the Apple VP acknowledging “my point that the iPad is not 100% charged when it says so. It's not the full admission that I would have liked, but it is actually more than I expected Apple would admit to.” In short, he sees Apple spinning how iOS mishandles its battery-powered device reporting.

Soneira concluded, “My essential point is simply that if the new iPad is fully charged overnight then my tests show it will run 11.6 hours, which is 1.2 hours longer than if it just charged to 100% (10.4 hours). This will matter to some users. If the iPad has cell and WiFi and background tasks running then I agree with Apple that it will cycle down and up. My lab tests were in Airplane Mode so that did not happen and I measured the true battery state.”

Besides if this is “normal” for the iPad family then why did an Apple representative tell CNBC that “If you charge it more than [when the battery indicator reads 100%], you could actually harm the longevity of the battery.”? Soneira thinks, “this was a misguided off-the-cuff remark by an Apple representative to make everything sound just fine. But if we take this statement at face value, it unfortunately implies that the new iPad is damaging its own battery.”

So does this matter? I think so.

100% means 100%. It doesn't mean, as Soneira found was really the case with the iPad 3, 90%. Anytime a company starts playing games with such a fundamental and important number as battery charge and its brother, useful battery life, I begin to wonder what's really going on here. 1.2 hours for a tablet, or any other battery-powered device, is a significant amount of time. Then, when you add in Apple's earlier comment about how constantly charging am iPad might damage the battery, you can only suspect that Apple is simply trying to talk its way out of trouble.

Apple needs to explain clearly and simply what's really going on with its batteries. As Soneira suggests, “Perhaps Apple should instead retract the [first] remark and graciously accept my interpretation and rescind their own remarks, which sound like very poorly thought out PR damage control.”

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Topics: iPad, Apple, Hardware, Mobility

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  • It's another example (along with the 4G claim).....

    .....of Apple constantly misleading gullible consumers!
    • Two things to consider:

      It's charged to 100% of Apples stated battery charge expectancy. i.e. 10 hrs. as advertized so 100% simply means 100% of the charge life advertized.

      Second, Apple is correct. Lithium batteries should not be over charged or you lose life. A battery that would hold a 11.2 hr charge will last 3 years when charged charged to 90% (10 hrs.). It will only last 1.5 years when charged to 100% (11.2 hrs). My husband is in the backup battery business and this is a fact.

      I will go with Apple on this one and ditch the Apple haters.
      The Danger is Microsoft
      • So why does Apple program the iPad to damage the battery?

        Apple puts circuitry in the iPad to protect the battery against overcharging. So if leaving it plugged in over night can damage the battery, why has Apple programmed it to do that?

        Of course you are correct that Li-Ion batteries should not be over charged. But it is not Dr. Soneira (who first drew attention to this problem) who would be "over charging" the battery by leaving the iPad plugged in over night. He did not hack the software or over ride any protections or the basic iPad charging routine. He just left a regular old iPad plugged in over night, and found that 100% of charge, when the iPad has been left plugged in over night, gives over an hour more run time than 100% of charge, when that reading first appears.

        Or do you contend that users are supposed to unplug the iPad the second that "100%" shows up on the charge screen? If so, I assume you will call on Apple to change its instructions to warn everybody that leaving it plugged in over night will cause it damage, yes?
  • It's not a bug

    It's a feature. Same old same old.
  • 4 days ago I wrote:

    I know Apple monitor the charge state of the batteries in all their computers very carefully (to optimise battery performance). I imagine the battery charges very quickly (all relative) to this "100%" then charges very slowly for two hours until the charge circuitry completely cuts the power.

    So this is showing something simpler than reality, where the battery is something like 95%+ charged, then takes two further hours of "trickle charge" to get to 100% (which is probably still someway of the theoretical maximum, to make the battery last longer).

    They probably do this so the user won't think "oh it's almost charged, I'll wait for it to hit 100%". You see "100%" (which is a reasonable approximation) and think "oh, cool, I can take it now".

    This might explain why many reviewers have found that the iPad exceeds Apple's stated figures for battery life. It would make sense for Apple to measure from "indicated 100%" to "flat", rather than "actual 100%".

    This seems like the most likely explanation for what we're seeing.


    This is pretty much what Apple are saying... Seems to make sense, yes?

    Also 100% (when it comes to batteries) doesn't mean 100% - nobody actually charges to the theoretical maximum, as doing so would severely limit the service life of the unit. But given it runs up fast then slows to a crawl (again to maximise the service life of the unit) this seems like a reasonable approximation (otherwise you'd have to explain to people that the "last few percent" will take a long time - so if you're wanting to take the thing don't wait for it, the law of diminishing returns has set in.

    Trying to educate users is pretty hard.

    Of course, given the huge capacity (electrically) of the (new) iPad battery this effect is much more noticeable, but this is far from unique.
    • Umm no

      The guy who found it measured the charge... There was 20% over the 100% Mark.

      Yes, this is likely a bug but, this is one of those bugs that benefits the consumer!
  • Waste of time...

    And this is important to - who? I have a new iPad and I don't care! It doesn't affect me at all. At night, I plug the iPad in to recharge it. It last me all day with no problem. I would be pretty confident that this is the case for most people. Who care if the battery is really at 100% when it shows 100%? Do you know anyone who watches it recharge and unplugs it exactly when it shows 100%? This is of interest only to tech geeks who always want to find something wrong.
  • I have seen the same thing on other devices

    This is not something only on the iPad, I have seen this on most of my rechargeable devices.
  • So we ate now up to what 7 stories about this none issue?

    Let me get this straight. The iPad itself works as expected. The battery itself functions as it should. The iPad gets in excess of 10 hours of use from a charged battery. The only thing is a minor disagreement about "how" that charge is represented. Big whoop.

    Pagan jim
    James Quinn
    • The Apple Haters care.

      That's why they down-voted your sensible post.
      The Danger is Microsoft
    • Did you eat right?

      Those stories must have been delicious if you counted them.
    • No the disagreement is in the Apple executive

      mention something he should have kept to himself, in that the battery charger does not work as claimed, as it is not stopping the battery from being charged, as he claims that overcharging it will hurt the battery.

      I find it disconcerting that Apple expects people to awaken in the middle of the night to disconnect their iPad from the charger, so as to not damage the battery.
      Tim Cook
    • Yes. Does it perform as stated? If yes, then it is a non-issue

      Battery charging is NOT exact, but a best guess based on several factors, such as heat generated (why a diode was placed against the battery on older devices as heat rose significantly whan fully charged) and internal resistance.

      However, there is no DIRECT measurement of the total charge available from a battery cell.
  • Does it last for 10 hours?

    Does the battery work for 10 hours after being charged to 100%? If so, Apple does what it says. Most likely the behavior is a balance between charging time, how long the device work after "100%" charged and battery life optimization. Perhaps it could be charged faster, but then it would survive fewer charges. Perhaps it could be charged longer, but then the users would be impatient. What Apple chose is a balanced approach that gives good enough performance and doesn't damage the battery.

    How many articles do you need to milk the issue dry? And... How many hits the site of "Dr. Raymond Soneira, president of DisplayMate, the world???s leading display and display tuning company, who found the battery problem" has got in the process"?
    • 10 hours

      No, apple chose to do what it wanted, not what you wanted. Usually for Apple, that is the path that leads you not to call them with complaints. Apples already got YOU and they truly do not care about YOU, the customer because they know one very immutable fact. You don't care about you either and you'll pay whatever they want you to pay every 6 months for an iPad and yearly for an iPhone. Because you believe everything they say no matter how absurd.
    • Sony states that batteries last longer if not fully charged

      They supply a 'Battery Care' app with their laptops to limit the maximum charge, depending upon whether you mainly use on battery (charges to 80%) or plugged in (charges to 50%).

      Since Sony is a major OEM battery maker, I would suspect that they know about the limitations of the technology.
  • Just something for Steven to whine about - it doesn't really matter

    Most people just plug it in overnight anyway. It's full when it's full and changing the battery algorythm won't change that.

    I've had a heck of a lot more problems with my Android 2.3 to 3.2 upgrade (from the vendor no less, no jail breaking here) and no one is saying anything about that.

    If this is all Steven's got on Apple, and he didn't even find it, it's pretty minimal.

    He should find a real problem
  • This is normal for Most Electronic Devices

    I don't know why this is such an issue. This is the way most electronic devices work. A laptop will charge to about 90%, it will show 100%, but then the charger will slowly charge the battery from 90% to 100%. If my memory is correct, this is done to prevent heat and electrical damage to the battery.
  • Enough with the 'Gates'...

    Every time Apple updates something, the press beings the search for a '-gate'; battery-gate, antenna-gate, overheating-gate, thisandthat-gate... It's a good thing Apple already admits that you can't dunk the iPad in water, because I'm not sure what they'd call that.

    There's quite possibly something here, much like the old issues with the display of bars on the iPhone. But it's also a fairly minor thing that plays into the narratives the press and bloggers like: Apple somehow misleads gullibile consumers, as the above; Apple is arrogant and won't admit mistakes; Apple is bad and Android is good. It really doesn't matter how important or not the issue is, or if it actually affects anyone, it's just if it fits the narrative. It's how the press works.

    The problem is, as Jeremy states quite well above, that the issue is complex; those who says "100% should be 100%!" as if the battery were a glass filling with water aren't being realistic. Apple is about consumer experience, not about technical wonkery. The 100% level is actually arbitrary no matter what, because as was said above, no battery charges to the theoretical max. If the battery level went to 90-95% fairly quickly, then took 8 hours ADDITONAL to go to 100% because of how the battery actually works, that's going to be annoying to most people. People who want their device 'fully charged' would complain that the iPad takes 16 hours to charge fully, even if all that extra time only gives an extra hour of use. It would be another '-gate'. So Apple sets the 100% threshhold at a point where diminishing returns take over, and where the user will get the hours of use Apple advertises.

    Yes, if an Andoid Manufacturer came up with a battery like the iPad's, they could (and probably would) put a meter on their tablet that reaches 95% and then a little icon would appear, and a pop-up would show that would explain "Now charging slowly because battery is nearly charged. Complete charge in 15 hours. But there are diminishing returns to continued charging. You can disconnect the tablet now if needed. Dismiss this warning? Y/N?" and the user could dismiss the pop-up and then it would show again the next time the user charged as a reminder, and eventually the user could find instructions online on how to go into the control panel and set the warning to be disabled. And Truth would be upheld, everyone would be better educated, and the user would totally NOT be annoyed.

    Yes. I'm being sarcastic. Or "100% is 100%" could be upheld, and the iPad would take a full day to charge, even though most people would be fine with a much shorter charge time, because 100 is 100, darn it! But wait... charging it for a full week, gives an extra 5 minutes of battery life! That's the real 100%! So change the meter again! Or wait, someone charged it for 3 months straight, and they discovered.....

    Or they could leave it as is; most people would be happy with getting the advertised battery life, plus a bit extra if it's plugged in all night. And the tech press can have something to be clever about. Yes, 1.2 hours is 'significant' but only because most laptop batteries last about 2-3 hours. If a Dell laptop reported 100% at 3 hours of use, but could really go another 15 minutes, would that be worth spending all this time on? But because it's Apple, it's worth it for the 'Gotcha!' and for the proof on how clever the person finding the issue is, and how devoted the reporter is to Fundamental Truth, and is totally looking out for you.

    Next we'll find out that when the battery meter reaches 0% and the system shuts down, there's technically a charge still in the battery, and it's not ABSOLUTELY empty, and the system could actually have operated another few minutes, but the designers chose to have the system shutdown gracefully instead... What? Really!? Get me the press!
    • Very good...

      Of all the replies I've seen on this topic, yours is by far the most cogent, and most likely correct. I just wish Apple would actually give this response, rather than the weird things it's said so far.