Your iPad battery may last longer if you don't charge it fully

Your iPad battery may last longer if you don't charge it fully
A few days ago, the news came out that the new iPad battery doesn't actually reach a full charge until about an hour after the battery meter reads 100%, and we said that it might be a good idea to leave your iPad on the charger the extra time to make sure you get your full amount of juice. But, that may not actually be the best idea. 

What we hadn't taken into account was the lifespan of the typical lithium-ion battery. You see, there is a tradeoff to be made between how full of a charge you keep per cycle with the overall lifespan of your battery. Batteries can't last forever, and eventually lose their ability to retain a charge. It turns out that charging your battery longer can speed up the degradation process that will forever kill your battery. Battery University found the difference in how fast your battery will degrade based on charging it to certain levels. 

Given that we've seen data saying the new iPad has a temperature of around 86F (30C) when charging, the difference between charging the battery fully and to just 60% is pretty substantial at that temperature. If you keep the battery around a 40% charge, your battery will only degrade 4% over the span of a year, but if you fully charge your battery, you could lose as much as 20% in the same period. 

It's possible that Apple factored in all of this and has set the battery meter to give a false reading in order to provide longer battery lifetimes, but there's no way to confirm that. Either way, maybe it isn't good to leave your iPad charging too long. 

Related phones

iPad 3
  • Display 9.7" 2048 x 1536 pixels
  • Camera 5 MP / 0.3 MP VGA front
  • Processor Apple A5X, Dual-core, 1000 MHz
  • Storage 64 GB
  • Battery 11560 mAh



1. remixfa

Posts: 14605; Member since: Dec 19, 2008

see.. its not a glitch, its a feature!! your charging it wrong!

2. Droid_X_Doug

Posts: 5993; Member since: Dec 22, 2010

remix - ya beat me to it. It IS a feature!

3. tedkord

Posts: 17489; Member since: Jun 17, 2009

Why would Apple need to worry about the battery degrading 20% in one year? By that time all the diehard Apple enthusiasts will be buying the newest iPad, regardless of it being an advance or not. A joke, folks. Don't get all knotted up.

9. _PHug_

Posts: 482; Member since: Oct 11, 2011

You beat me to my comment but it's not a joke

4. NOKIA.8800.ARTE

Posts: 100; Member since: Mar 26, 2012

Nice inception... but its a lengthy progress....

5. Bluesky02

Posts: 1439; Member since: Dec 05, 2011

First, the battery doesn't charge fully as intended Second, if you decided to charge fully your battery will start to degrade. Strange product, for iFan logic

12. theoak

Posts: 324; Member since: Nov 16, 2011

This is not "just" Apple ... this applies to any lion based battery.

6. wendygarett unregistered


7. rallyguy

Posts: 620; Member since: Mar 13, 2012

Nothing new here. This is why US military equipment that uses Lion and LiPoly only gets charged to 70%. The charge doesn't last as long but the service life is drastically extended, Of course no consumer product is going to say this because they would have to put in a battery that is 30% larger but only charged to 70%.

14. theoak

Posts: 324; Member since: Nov 16, 2011

Finally someone that "gets" that this is a lion battery "issue". This has NOTHING to do with Apple. ANY lion battery is going to have this issue. Lion batteries are used in almost everything these days ... not just phones.

8. frydaexiii

Posts: 1476; Member since: Dec 01, 2011

Seem to me like Apple is deliberately placing these glitches here and there just so they can "fix" them in the next iOS update so their customers think they "care". Pretty good marketing...

10. _PHug_

Posts: 482; Member since: Oct 11, 2011

Since I love conspiracy theories I am going to start stating this as fact

13. theoak

Posts: 324; Member since: Nov 16, 2011

This applies to ... ANY ... lion battery. Lion batteries are not just in Apple products ... but are also in HTC, Motorola, LG, Sony, etc ... and really any device that uses lion batteries. My portable drills use lion batteries for example. I have 3 batteries that I swap around ... when not in use ... I put them in my fridge to extend the life of the battery.

11. andro.

Posts: 1999; Member since: Sep 16, 2011

Ifans are getting very afraid these days to charge to ipads because if the faulty charger does actually charge it now they dont know wether to partially charge it or leave it charge for longer than the 100% mark! All the pr guff about the ipads new better battery is hilarious now especially as that battery is overheating to the point of being a portable cooker for camping trips. You gotta laugh at those ifans yet again caught with yet another apple resolutionary faulty product

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