How to use a Macbook in terms of power

Discussion in 'MacBook Pro' started by jama12uk, Mar 5, 2011.

  1. jama12uk macrumors newbie

    Mar 2, 2011
    I had been looking at windows laptops and various shops had said that when the laptop was sitting at a desk and using mains power, to remove the battery as leaving it plugged in after 100% charge will damage the battery.

    My question is, if the batteries in the Macbook Pro and Air (I will get one or the other) are not removable, will leaving the laptop plugged in when fully charged damage the battery? I understand that I could simply unplug the laptop and use it off the battery but then I'm using up charge cycles needlessly. Does the charger cut-off power supply to the laptop when charging reaches 100% and so doesn't damage the battery?

  2. miles01110 macrumors Core


    Jul 24, 2006
    The Ivory Tower (I'm not coming down)
    The best practice is to use your machine how you need to use it instead of letting artificial concerns like "battery life" dictate your lifestyle. You can always replace the battery if it gets really bad.
  3. polkunus macrumors member

    Feb 15, 2011
    That... costs money.
  4. jama12uk thread starter macrumors newbie

    Mar 2, 2011
    I hear what you are saying but with such an expensive piece of hardware looking after it is important. I agree that this should not get in the way of usage but looking after things correctly does indeed make them last longer. I am planning to hold on to a mbp for as long as possible without shelling out on avoidable repairs.

    Look after your tools. I wouldn't care so much if it was covered in external scratches as the mbp is a tool but if I can look after the hardware all the better.
  5. Apple 26.2 macrumors 6502a

    Apple 26.2

    Jan 1, 2011
    What up, 212?!
    It's recommended to pull the plug and run/drain the battery every now and again, but no, leaving it plugged in will not damage the it.
  6. macbookprose macrumors newbie

    Feb 21, 2011
    That's good, but can you cite something for that?
  7. Matthew9559 macrumors 6502a


    Apr 7, 2007
    Cleveland, OH
    You can find info about this in the manual that comes the MBP (though that was early 2008). I would assume it's still in there. It's definitely on apple website.

    I generally calibrate my battery once every other month (Charge to 100% battery life, use it until it dies and them charge fully again). I think most sources recommend once a month though.
  8. TomCondon macrumors regular

    Nov 26, 2010
    all you have to do is let the electrons in the battery move once in a while :)

    so just dont use it like a desktop and you'll be fine
  9. Rhyalus macrumors 6502


    Mar 4, 2011
    I have never heard of such a thing.

    I would turn it around and say that you should get proof that using a laptop like every other person in the world is "bad" - not the other way around.

    Using a laptop while hooked up to AC is perfectly fine.

    As someone said, run the battery down completely every month or so - this is a well documented technique to calibrate the battery meter and to maximize charging potential.

  10. jama12uk thread starter macrumors newbie

    Mar 2, 2011

    When charging aa batteries e.g. sanyo eneloops, leaving them charging is really damaging as the batteries are kept constantly warm. This radically reduces their useful number of charge cycles (shortens lifetime). Just wondered if this was the case with macbooks.

    I am not suggesting anything, I simply do not know and so am asking the question.

  11. bpaluzzi macrumors 6502a


    Sep 2, 2010
    Any proof of that? Have never heard of such a thing. Not disagreeing, would just be interested in seeing if that was the case.
  12. Rhyalus macrumors 6502


    Mar 4, 2011
    I think this is true. AA battery chargers (NiMH or older) are not supposed to be used constantly. I don't have any references, but I do remember reading this in the manuals when I have purchased these things.

    This is not at all related to laptops, lithium batteries and expected mode of operations.

  13. Sanderr macrumors regular

    Jun 14, 2007
    Just make sure to use it without the charger connected from time to time. In 4 years I have never thought about it, just plugged it in whenever there is power available. After these 4 years of at least 6 hours a day of usage, my battery health is still at 96% so don't worry too much about it ;)
  14. Miss Terri macrumors 6502

    Nov 11, 2010
    US East Coast
    From a person who just bought a few sets of Eneloops for the first time, and JUST charged one set for the first time yesterday, thank you! I had not heard this information.

    While I don't generally tend to leave things like chargers plugged in and going after they are "done," I will now make a point of not doing it with the Eneloops.

    On the laptop battery: I hear you about wanting to know. Sure, you could just go along as is, but there is satisfaction in knowing whether what you are doing is the best way or not (even if you choose not to be a "slave" to it for one reason or another). At least that way it is a choice in how you treat it, and not you just doing something arbitrarily. It's like knowing how often to change the oil in your car.... even if you go over a bit from time-to-time.

    This is purely anecdotal, but I've owned Mac laptops since my first Duo (kind of like the original Air concept :cool:), and I've never heard or read anything about running with the computer plugged in once the battery is fully charged to be a problem. I *have* read that you should not run with it plugged in 24/7/365. Apple used to describe the best usage as something like "Use it plugged in at home, use it on the train to work via the battery, plug it in at work and then use it more." In other words, pretty much ignore it except make sure to give the battery a workout some of the time.

    I used this plan on my 2001 iBook, and the battery lasted 7 years before getting noticeably weaker. And that (actually, this, as I'm typing on it right now :D) computer lived for three years in the hot, humid, salty tropics (and no, I was not able to leave it at half charge whenever it was stored in a hot area).

    I have read that fully charged or fully emptied Li-Ion batteries don't like to, say, be left in a hot car or stored for a loooong period of time. I think then you are supposed to leave it at about half charge.

    I'm sorry this is not cold, hard fact, but at least it will give you some ideas to look for corroboration on via search or etc.

    Enjoy your new Mac! :)

    Miss Terri
  15. jama12uk thread starter macrumors newbie

    Mar 2, 2011

    Congratulations on the Eneloops, they are a truly remarkable piece of tech. The new versions now last 1500 charges and unlike regular lithium ion or polymer batteries they hold the charge. In led torches and digital cameras their lifetime is amazing when compared to regular rechargeables.

    Thanks for the information, im sure I will be fine. The consensus seems to be that the macbook batteries are far superior to other laptops. This will be my first mac.

  16. DudeMartin macrumors regular

    Dec 2, 2010
    Chicago, Illinois
    I don't think it harms the battery. Because when the charge is full, on the battery indicator you see a little plug icon, not a little lightning bolt. I assume that it means that the computer is now running on the charger, not the battery. Plus using the battery wears it out anyways, so any time you recharge your battery, you decrease it's life by a bit anyways. I think that if you can keep it plugged in, do so.

    However, it is good to drain the battery once or twice a week in order to keep the battery alive (to keep the flow of electrons in the battery).

    So... if you always run on battery - it will die faster, if you never run on battery - it will also die faster, however if you combine using the charger and battery, then you will get optimal battery life.
  17. BookieBear macrumors newbie

    Feb 24, 2011
    On my old windows laptop the manual said never leave it plugged in after it is fully charged as the battery is constantly being charged to 100%. Not sure if this applies to Mac's though.
  18. jama12uk thread starter macrumors newbie

    Mar 2, 2011

    Thats exactly what im familiar with. :(
  19. Mal macrumors 603


    Jan 6, 2002
    It does not apply to Macs, nor most modern laptops. The computer automatically stops charging the battery and just maintains a trickle flow of power to keep the battery in good condition. It's recommended that you use it on battery occasionally (and it's best to run it all the way down, to at least 20% charge, before recharging usually), but leaving it on the charger is not an issue.

    I'm surprised GGJStudios hasn't chimed in with his link yet.


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