So does running your battery down close to the end hurt your iphone?

Discussion in 'iPhone' started by The Game 161, Mar 25, 2011.

  1. The Game 161 macrumors P6

    The Game 161

    Dec 15, 2010
    Some have mentioned that when you get just below 20% you should charge your phone up.

    So letting your phone go down to 5-10% is a big no no?
  2. gpc17 macrumors regular

    Aug 11, 2010
  3. Interstella5555 macrumors 603


    Jun 30, 2008
    Some have said a lot of things, most of them untrue.
  4. Jumpman2033 macrumors regular

    Jun 27, 2010
    I wouldn't think running it low would hurt. The only thing that may would be killing it often. I look at draining the battery completely like doing a hard shut off (like pressing and holding a computer's power button when it freezes). Once in a while not a big deal, but shouldn't be normal practice.

    Just my thoughts though, and i am by no means an expert.
  5. maflynn Moderator


    Staff Member

    May 3, 2009
    From all that I've read, regardless of the battery technology. Deep drains seem to hasten a batteries demise. That is deep drains shorten the potential life span.

    My purely unscientific research seems to bear this out. My wife who has a habit of donig just that seems to have battery issues with it not holding a charge as long as it used too. This seems to occur about a year of usage, where as my phones where I try to keep topped off most of the time where its feasible perform better.
  6. jacollins macrumors 6502a

    Jun 19, 2010
    The battery's lithium-ion. Lithium-ion batteries don't like being completely drained (will kill them dead fast) and like being topped off.

    That said, every manufacturer knows Lithium-ion has problems when they are drained completely, and has hardware in place so you can't drain it through use. 20% is really like 25%. But you can't use that last 5%. You can still damage it if you take it down low and then leave it for a month uncharged though.
  7. Asha'man macrumors newbie


    Jul 15, 2008
    Atlanta, GA
    There are 3 things that shorten the lifespan of your battery:
    1. draining it
    2. charging it
    3. letting it sit

    No, seriously.

    The deeper you discharge your battery, the fewer charge cycles it will support. So draining it to 20% cuts it's life slightly, but draining it to 5% cuts it's life more. But charging all the way to full, and especially holding it at full for a prolonged duration, also slightly reduces it's life. However, time alone is also causing the battery to degrade, so 5 years from now it won't have the same capacity it has while new, even if you never charge/discharge it.

    But all of these effects are pretty subtle, and probably aren't worth worrying about. If you are a typical user and replace your phone with the newest/greatest after 2 or 3 years, your battery will probably be just fine no matter how you treat it. A good lithium battery supports thousands of full discharge cycles, which is probably far more than the device it's in.

    But if you want to get the absolute maximum life from your battery, charge it more often, not less. I plug mine in every night, even if it's still at 75% charge. There's no reason to wait until it's down to 20% or even 50%. If you treat the battery well, it might be good for 3,000 cycles instead of 2,000 cycles, but you probably won't even notice the difference.

    Oh, and for long term storage of a lithium battery, the advice I've seen is to discharge it to about 60% and store it in the fridge, that reduces the effect of aging noticeably.
  8. RebeccaL macrumors 6502a


    Jan 1, 2011
    This has been asked many times. Forget about everything you read in forums. Apple has an official page on iphone battery information. They say you SHOULD completely drain the battery and recharge it at least once a month. This in lion batteries is used to calibrate them.
  9. DiamondGCoupe macrumors 6502

    Nov 12, 2007
    I wouldn't do that with a laptop battery but the iPhone battery will last far longer than you or anyone will be using it. Apple recommends charging before 10% after the initial battery cycle (which requires it to completely drain).
  10. MauiGideon macrumors regular

    Sep 5, 2008
    The only answer with a legit source... Ya I think I'll trust this one:D
  11. diamornte macrumors regular

    Apr 27, 2009
    LOL @ all the false know-it-alls.
  12. RebeccaL macrumors 6502a


    Jan 1, 2011
  13. iApples macrumors 65816


    Mar 24, 2011
    I completely kill all my batteries on my phones/laptops before I charge them. Actually not so much on my phone. I usually throw that on the charger every night no matter what percentage it is. I've had no problems with my batteries.
  14. PNutts macrumors 601


    Jul 24, 2008
    Pacific Northwest, US

    Thank you for saving me the trouble.
  15. RebeccaL macrumors 6502a


    Jan 1, 2011
    You're welcome. I love giving tech advice online.

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