Battery Questions

Discussion in 'MacBook Pro' started by stevebook, Jun 15, 2007.

  1. stevebook macrumors member

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    Jun 15, 2007
    #1
    I have some questions about the battery in my macbook (preservation, use, calibration)

    What's the BEST way to ensure the longest life of the battery? I think the majority of the stuff I have seen says to (if possible) use the battery until about 50% and then charge it, perform full cycles every 2 months. Currently I can have the battery plugged in at almost all times, however i've already racked up 2 cycles because it has gone below 95% and just charged that little bit when I plug it in to use it.

    I just read about the calibration of the battery. When should this be performed? I have already used the laptop and performed the original charge (battery came discharged). Should I perform the calibration process ASAP or wait until it's time to do the full discharge (2 months?)

    From what I've read, here's what I would assume to be the proper use of the computer. I will be using the computer at school.

    Never fully discharge the battery if you don't need to, however do this about every two months. When using the computer by a power outlet, fully power it after it's day use and leave it plugged in and keep the full charge until next use (the next morning). Don't recharge the battery when it is about 80-95% full. Use it without AC power and allow it to discharge to about 50% before you plug it in.

    Is any of this right? Should I calibrate now or later?

    Steve
     
  2. aquajet macrumors 68020

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    Feb 12, 2005
    Location:
    VA
    #2
    You should read this.

    I don't fret too much about how often and how much I should discharge a battery to ensure maximum life. I use the battery whenever I feel like it, and that usually means I end up cycling the battery several times a week. It might be a shallow discharge, or a deep discharge. For reference, my battery has 198 cycles since November 2006 and still has 92% capacity. Not too bad considering:

    "A properly maintained Apple notebook battery is designed to retain up to 80% of its original capacity after 300 full charge and discharge cycles."​

    If you've never calibrated your battery, then it's probably a good idea to go ahead and do so.
     
  3. thehype31 macrumors member

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    Mar 31, 2006
    #3
    I think the best thing you can do for a battery is to use it. If you let your laptop sit on a desk for extended periods of time without using the battery, you'll lose maximum capacity. On my 15 month old ibook, I have 380 loadcycles, and it still has 83% maximum capacity... I routinely run the battery down just about every day. So, in essence, it is calibrated mutilple times a week, since I run the battery down fully, then just plug it in overnight so it recharges fully in the sleep state. Anyways, heres the coconut battery screen shot:

    [​IMG]

    :apple:
     
  4. stevebook thread starter macrumors member

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    Jun 15, 2007
    #4
    Should I calibrate the battery now or before I actually need to use it? (like traveling or outside of home for 3+ hours)

    To my understanding all the calibration does is fix the estimated time left in the charge given by OS X and therefore would fix a prematurely shutting down machine (because OS X shuts down to save work when it believes there is a short time left for the battery)
     
  5. masse macrumors 6502a

    masse

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    #5
    Any hopes of increasing the capacity of a battery that's at 60% of its original max?
     
  6. mad jew Moderator emeritus

    mad jew

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    Location:
    Adelaide, Australia
    #6


    Calibrating the battery prevents the adaptor from overcharging (or undercharging, but that's not so much of a problem) the cells. Overcharging can be harmful to your battery and it can reduce your battery's life to varying degrees. Calibrate your battery when you first get a machine, and monthly from then on. As a rule of thumb, this should work for most users to help get the maximum life out of their batteries.



    Not really. Batteries are classed as consumables. They're meant to be used up and replaced. The best hope you've got is to calibrate it peridoically and treat it well over the remainder of its life. :)
     
  7. stevebook thread starter macrumors member

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    Jun 15, 2007
    #7
    I've already given it a full cycle to charge it and now used it. The battery is at about 60%. Should I perform a calibration now or in a month?
     
  8. mad jew Moderator emeritus

    mad jew

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    #8
    You may as well calibrate it now. The full power cycle thing isn't enough anymore, even though that used to constitute recalibration.
     
  9. stevebook thread starter macrumors member

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    Jun 15, 2007
    #9
    So calibrate now and then again every month?
    Sounds good
    Any other tips
    I know I should stay away from continually draining the battery
    So should I get it to about 50% each time before the recharge?
     
  10. mad jew Moderator emeritus

    mad jew

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    #10
    Yep, you're on the right track. Don't wait for 50% charge before putting it back on the adaptor though. This'll just cause unnecessary wear on the battery. When possible, run it from the adaptor no matter the charge level. :)
     
  11. stevebook thread starter macrumors member

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    Jun 15, 2007
    #11
    I'll be using it at school. So what I should do is just keep it plugged in whenever possible?
    The thing i'm worried about there is trickling (having the level drop below 95% when it is not in use and then having an unnecessary cycle when I plug it in)
     
  12. mad jew Moderator emeritus

    mad jew

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    #12
    Well don't let it worry you. That small cycle, as unlikely as it is, is better for your machine that constantly running from the battery for the sake of it. When plugged into the adaptor, the laptop will only get power from the battery when absolutely necessary. Assuming you don't have dodgy power wherever you're plugged in, this means it'll only tap into the battery when under extreme use, often but not always a result of power-sucking USB peripherals. If you're near a power adaptor, use it. :)
     
  13. stevebook thread starter macrumors member

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    #13
    So using the battery would conceivably produce worse wear than a little 1% charging cycle.
    And whenever I get to a power outlet, I should use it.
     
  14. mad jew Moderator emeritus

    mad jew

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    #14
    Mmm, sort of. It's all about balance. Trust me, the best way to use a laptop in terms of battery conservation and longevity is to keep it plugged in when possible and calibrate it monthly. Don't wait for the machine to drop to a certain charge level before plugging it in though, that's pointless.
     
  15. stevebook thread starter macrumors member

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    Jun 15, 2007
    #15
    so even if I had to use it for a little bit
    and it's sitting at like 90%
    just charge it from there?
     
  16. CalBoy macrumors 604

    CalBoy

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    May 21, 2007
    #16
    Is this really the only thing to consider when leaving the notebook on AC power most of the time? I thought that extended periods of time would eventually cause the battery to lose some capacity? I thought that some power needed to flow from the battery? If this is really all that there is to it, then a laptop battery should last for years.
     
  17. mad jew Moderator emeritus

    mad jew

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    #17

    Yep.



    You're right about the batteries needing some flow through them. That's where monthly calibrations help. The average user would take their Mac off the power for a wee bit of time during the month anyway, and that should be enough to ensure the electrons keep flowing. :)
     
  18. stevebook thread starter macrumors member

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    #18
    well that's why you do calibrations / full discharges once every month or so
     
  19. CalBoy macrumors 604

    CalBoy

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    May 21, 2007
    #19
    See, that makes perfect sense, but the Apple website makes it seem like a frequent discharge is needed. Something on the order of a daily drain (read the part about the commuter). Whatever, I'm keeping it on AC most of the time. I'll discharge for calibration and those times when an outlet isn't near. Thanks for the info mad jew!
     
  20. mad jew Moderator emeritus

    mad jew

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    #20
    No worries mate. The Apple site makes a good point, but you don't need to discharge it daily. I just sold my iBook G4 with its original battery. It was still getting well upwards of four hours battery life with full screen brightness and AirPort still on, after three and a half years of use. It all comes down to treating the battery well. :)
     
  21. stevebook thread starter macrumors member

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    Jun 15, 2007
    #21
    and you treated it the same way you told me?
    monthly full discharges
    plugged in whenever possible?
     
  22. CalBoy macrumors 604

    CalBoy

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    May 21, 2007
    #22
    That's good to hear. I would like my mbp to last a full five years, at least I hope. Hence the reason why I over-bought and went with a mbp now. In any case, I can always buy another battery if this one can't hold a charge in two or three years. Thanks again.
     
  23. mad jew Moderator emeritus

    mad jew

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    #23

    Yep, and it probably dropped its battery uptime by half an hour over the whole time. :)
     
  24. stevebook thread starter macrumors member

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    #24
    thanks for all your help
    i couldn't find a straight answer for this anywhere!
     
  25. mad jew Moderator emeritus

    mad jew

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