Keeping it Charging 24/7 Ruin Battery?

Discussion in 'MacBook Pro' started by Finox831, Aug 2, 2014.

  1. Finox831 macrumors member

    Jul 28, 2010
    Hey, so I just bought a MBP 13" a few days ago and I have it connected to my monitors at home with the charging cable on. Whenever I need to take my laptop on-the-go I unplug it, which is maybe once or twice a week. Will keeping it charging at 100% battery for long periods at a time ruin the battery life or anything? thanks
  2. snaky69 macrumors 603

    Mar 14, 2008
    No. Battery myths such as this one dates from the old Ni-Cad days and need to die a painful death.

    Your cell phone battery is the same type of battery that is in your computer. Charge it and discharge it as you please, you're not going to damage it.

    Plug it in when you need to, unplug it when you need to. Just don't leave it plugged in 100% of the time, unplug it once in a while(like, once a month) just to keep the juices flowing.
  3. TheDrift- macrumors 6502a


    Mar 8, 2010
    No, it'll be fine.

    When I first got my mac I worried about this too, no need.

    I have hammered my battery for 4 1/2 years and think still in low 90's high 80's capacity...

    ..worry about something else instead ;)
  4. nostresshere macrumors 68030

    Dec 30, 2010
    Is this for real, or another myth?
  5. MattZani macrumors 68030


    Apr 20, 2008
    If it's plugged in 24/7, honestly look at an iMac, so much more for the money. But if you at all need the portability, the times when you're not using it at a desk will be more than enough to keep the battery in good health.
  6. Weaselboy Moderator


    Staff Member

    Jan 23, 2005
  7. MCAsan macrumors 601


    Jul 9, 2012
  8. M5RahuL macrumors 68030


    Aug 1, 2009
    My 2012 rMBP stayed plugged in most of the time I owned it...When I sold it, 10 months later, it had a total of 6 battery charge cycles.

    The battery life was at 101% the day I sold it. I, however, intentionally would unplug it once every few weeks for ~ an hour, whether being used or not.

    Since I got the 2013 version, I just plug / unplug as desired..
  9. cube macrumors G5

    May 10, 2004
  10. nostresshere macrumors 68030

    Dec 30, 2010
    I see people say this all the time - get an iMac.

    BUT - my computer is almost always plugged in at my desk at home or desk at work. An iMac is not going to be a good solution for that.
  11. simonsi macrumors 601


    Jan 3, 2014
    Pretty clear he meant plugged in in one place, no-one is suggesting an iMac is portable...

  12. Pentad macrumors 6502a


    Nov 26, 2003
    The 90's called, they want their advice back.

    Actually, this advice used to be true a long time ago. However, Apple's power management is very smart and does not continually charge the batter when it is plugged in.

    Apple even had a video that talked about this with the introduction of the MBP Unibody.

  13. exnihilodub macrumors newbie

    Jul 18, 2014
    the battery lifetime is described as 'cycles'. these cycles are the "deplete/charge" amount. Let's say your the manufacturer designated your battery life as "3000 cycles" which means after depleting your battery approximately 3000 times, your battery will not function properly.

    When you plug the macbook on charge on a 100% full battery, it feeds itself off of the power supply. So it is more healthy for your battery ( just plug it out while you power off/sleep and to calibrate battery, let it drain completely once in a while). But to make things clear, your battery is still charging itself minimally while on 100% and plugged in. (that's a really minimal charging, nothing to be worried about)

    Go to your system information dialog and under Hardware->Power you will see your cycle count. check: to see your mac's maximum cycle count so you can see where your battery stands.

    Also there are some programs showing how much charge your battery could hold when it was out of the factory and how much it can hold now.
  14. Weaselboy Moderator


    Staff Member

    Jan 23, 2005
    It is true. Read the official statement from Apple at the link I posted. They say to run it on battery occasionally.

    You are correct the Mac portables have circuitry to prevent overcharging, but that is a different issue.

    snaky69 is right on target here.

    Here is the relevant quote from the article.

  15. T5BRICK macrumors G3


    Aug 3, 2006
    Completely draining your battery to calibrate isn't necessary on any of the newer Macs with built in batteries.
  16. TheDrift- macrumors 6502a


    Mar 8, 2010
    Ok just checked my battery after 4 years of abuse my battery is at based on that about 1.5% a its gonna 10 years to reduce your capacity by about 15%!

    Not worth worrying about imo use it as you want :)
  17. Badrottie Suspended


    May 8, 2011
    Los Angeles
    At college last year I leave it plugged in all the times. Do not worry. :apple:
  18. Khronoschoty macrumors newbie

    Aug 3, 2014
    I did a lot, I mean a lot of research about batteries, and even specifically the MacBook Pro. In short it's actually healthy to leave it plugged in 24/7 but let it discharge once a month (meaning of course unplugging once a month)
  19. pragmatous macrumors 65816

    May 23, 2012
    "Apple does not recommend leaving your portable plugged in all the time. "


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