Apple Disputes DisplayMate iPad Charging Claims

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iPad Battery Charging

Apple responded Tuesday to concerns regarding the 2012 iPad’s battery, assuring consumers that the battery, which continues to charge even after the capacity indicator reaches 100 percent, operates as intended. In a statement, the company said the described behavior is a feature, not a bug, that’s always been a part of iOS.

The issue in question, first reported late last week by video diagnostic and testing firm DisplayMate, is that the new iPad continues to draw a full 10 watts of power for over two hours following an indication by the on-screen battery meter the the device’s battery is at “100 percent.” 

“At 2:00 hours after reporting 100% charge, the new iPad hardware started to reduce the charging power. At 2:10 the recharging cycle fully terminated with a sharp decrease in power. The new iPad battery is truly fully recharged 2 hours and 10 minutes after prematurely reporting on screen that it was fully charged,” DisplayMate’s Dr. Raymond Soneira told

While it has been determined that the significantly larger battery in the 2012 iPad will take noticeably longer to charge than that of its predecessor, a necessity considering the increased power requirements of the most recent device, the battery capacity reporting issue concerned consumers and media alike. It appeared that, due to the supposed error in the capacity calculation, the iPad’s battery was truly only at 90 percent despite reporting 100 percent capacity.

In an attempt to address the concern, Apple VP of Product Marketing Michael Tchao spoke with AllThingsD Tuesday, stating that the confusion over the iPad’s battery charging stems from the way that all iOS devices handle the last portion of the charging process in an effort to preserve the longevity of the battery.

Michael TchaoMichael Tchao, Apple VP of Product Marketing

According to Mr. Tchao, the latest iPads, along with all previous iOS devices, report the device as “100 percent” charged just before the battery actually reaches maximum capacity. From there, iOS will intelligently charge the battery to a “true” 100 percent, then discharge a point or two before recharging to 100. This process repeats until the user unplugs the device, ensuring that the battery remains fresh no matter how long the device is plugged in.

“That circuitry is designed so you can keep your device plugged in as long as you would like,” Mr. Tchao said. “It’s a great feature that’s always been in iOS.”

The decision by Apple to not display these small increases and decreases of capacity via the battery meter was made with the goal of not distracting or confusing consumers who, without knowledge of the way iOS handles battery charging, might believe that their device was malfunctioning. But regardless of what stage the charging process is at when the user unplugs the device, if the battery meter reads “100 percent,” the iPad will still operate for at least the advertised 10 hours, Mr. Tchao said. 

Dr. Soneira, while pleased to see a response from Apple regarding matters of this character, was still not entirely convinced by Mr. Tchao’s explanation.

“If the iPad has cell and Wi-Fi and background tasks running, then I agree with Apple that it will cycle down and up,” Dr. Soneira said. “[But] my lab tests were in Airplane Mode so that did not happen and I measured the true battery state…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% [on the meter], or 10.4 hours. This will matter to some users.”

Speaking with AllThingsD on the matter, Yankee Group analyst Carl Howe summarized the situation by pointing out that battery charging processes are as much art as they are science.

“What’s really subtle is that consumers think they understand that 100% means ‘full’,” Mr. Howe said. “That might have been the case with older batteries, but today’s batteries have microprocessors managing their charging. So 100% is whatever that microprocessor says it is — it’s not any absolute measurement of ion concentration or anything…If it says it’s charged, consumers should assume it is, and not worry about whether the charger is drawing current.”

Battery image courtesy of Shutterstock, labels by TMO.

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Lee Dronick

In a statement, the company said the described behavior is a feature, not a bug

Oh the Apple bashers are going to have fun with that statement.


So basically Dr. Soneira is upset that the battery indicates 100% and gets the advertised run time, but if the iPad is left to charge longer, it gets a little more run time.

Some of us, in this world of advertised “up to” levels, are thrilled that Apple actually delivers as promised. Even my 3 year old iPhone delivers run time close to what it did when new. My 2 year old iPad runs as long as it did on day 1. Can’t complain about that.

Well, I could, if I wanted to gain a boatload of clicks in a hurry, but really? This is a non-issue, folks.


Actually I VERY GLAD to hear these details about the battery charging process.
After leaving my MacBook Pro plugged in for several years (and rarely using it on battery alone), my battery gave a worthless 8-10 minutes.  Apple didn’t stand by the battery and I had to buy a new one, basically with the understanding that the new battery would probably get ruined as well (at least without a LOT of intentional supervision by myself to de-charg it).
So I was wondering IF and WHEN Apple would EVER try to address the battery life vs de-charging issue.  GLAD to hear that they have been working on it.  Surprised that they haven’t disclosed these details to the public earlier.  (I’ve been reluctant to purchase more MBPs with the intention of primarially using them as desktop machines.)
Now, can anyone tell me if the battery charging issue has been addressed in the old MBP (2.2 2007) ........or am I still at risk of ruining this battery by not de-charging it fully and regularly.  (I’m assuming that Apple wasn’t able to make these changes to older battery technology…..unless it could be changes in the software.)

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