MBP battery questions

Discussion in 'MacBook Pro' started by jon08, Dec 6, 2008.

  1. jon08 macrumors 68000

    Joined:
    Nov 14, 2008
    #1
    I will be getting a previous generation MBP soon and will be using it mostly as a desktop replacement.

    I was wondering a couple of things about MBP battery tho:

    1) First of all, when I receive the laptop, how many hours should I charge it before using it for the first time? (Usually, about 9 hrs is recommended, isn't it?)

    2) Is there any difference in performance at all, whether the laptop is plugged in, or solely on battery? (Because on my current Toshiba laptop I have a feeling that when on battery, at times laptop's performance is slightly worse than otherwise).

    3) What would be the best way to preserve the battery life? Can I keep it in my laptop all the time, even when it is plugged in (when at home), or should I rather keep using up the battery first and then when it's about to run out plug it in? Or will it not really make any difference with either because after all the battery's life expectancy is 2-3 years and will come to an end sooner or later anyway?


    Thanks in advance.
     
  2. nerdbert macrumors regular

    nerdbert

    Joined:
    Nov 7, 2007
    Location:
    Berlin, Germany
    #2
    2) To me it's barely noticeable, but I don't encode videos or do anything else which really sucks energy when it's not connected.

    3) I always keep the battery attached, because even though I barely use it outside it saves me whenever I stumble over the cable or when I want to move to another room without shutting it down.
    I just make sure that the battery doesn't drop below ~95% so the MBP doesn't charge it. This way I'm avoiding unnecessary charging cycles.

    However, if it really stays on one desk all the time you could charge the battery to about 60% and keep it in the fridge. Under this condition it will age less slowly than inside the laptop, which keeps the battery hot and at 100%.
     
  3. jon08 thread starter macrumors 68000

    Joined:
    Nov 14, 2008
    #3
    Hm, I'm not quite sure what you meant by that?
     
  4. infernohellion macrumors 6502

    Joined:
    May 14, 2006
    Location:
    København
    #4
    I think this should be enough:
    http://support.apple.com/kb/HT1490
     
  5. nerdbert macrumors regular

    nerdbert

    Joined:
    Nov 7, 2007
    Location:
    Berlin, Germany
    #5
    Maybe that was a little cryptic ;)

    What I wanted to say is that when at home or work I never leave the computer unplugged for more than a few seconds. That way the battery rarely reaches a level which makes the MBP charge it (I don't know at what level it does, but if you connect the laptop and the battery is at 95% it won't charge).

    What hurts the battery most is charging it from around 80% to 100%. So the most efficient way to ruin the battery would be to unplug and wait half an hour, then plug it back in.
    So when I take my computer from the living room to the kitchen I take the cable along and plug it in right away.

    BTW: For this reason some people use tools which abort charging at 80%. Might limit the time on the road, but gives better battery life.
     
  6. kobefan234 macrumors 6502

    kobefan234

    Joined:
    May 12, 2008
    #6
    For step one of the calibrating where it says Plug in the power adapter and fully charge your PowerBook's battery until the light ring or LED on the power adapter plug changes to green and the onscreen meter in the menu bar indicates that the battery is fully charged.

    Should your Macbook pro be on or off ? when doing step one?
     
  7. jon08 thread starter macrumors 68000

    Joined:
    Nov 14, 2008
    #7
    I'm assuming that if this would be your first time charging the notebook, then I'd say it needs to be turned off...
     
  8. kobefan234 macrumors 6502

    kobefan234

    Joined:
    May 12, 2008
    #9
    I got my new macbook pro form the apple store like 2 days ago and i installed coconut battery and it said the age of my mac is two months

    [​IMG]
     
  9. DeusInvictus7 macrumors 68020

    Joined:
    Aug 13, 2008
    Location:
    Kitchener, Ontario
    #10
    It was probably manufactured at that time, that's why it is saying 2 months old. For example, I received my MacBook on Oct. 21, and when I installed coconutBattery, it said my MacBook was 2 weeks old. So I'm thinking it was manufactured at that time.

    Hope that explains it a little.
     
  10. kobefan234 macrumors 6502

    kobefan234

    Joined:
    May 12, 2008
    #11
    ^^ thanks that made me feel better :)

    and also how do you know when you calibrated your battery right?
     
  11. DeusInvictus7 macrumors 68020

    Joined:
    Aug 13, 2008
    Location:
    Kitchener, Ontario
    #12
    Umm...you don't really, I guess if the reading on the battery indicator on the menu bar is accurate, meaning that it tells you that you're on reserve battery with I think 5% (Someone correct me on that) left, then I would think you have done it correctly.
     
  12. kobefan234 macrumors 6502

    kobefan234

    Joined:
    May 12, 2008
    #13
    I dont really get it but oh well i i will try and see if i get better battery life;)

    wtf i just checked coconut battery and my battery health went down to 99%

    [​IMG]
     
  13. infernohellion macrumors 6502

    Joined:
    May 14, 2006
    Location:
    København
    #14
    I think you shouldn't get too stressed out over the battery life. Any programs used to see battery capacity to date is not 100% accurate.

    Enjoy your new MBP :)
     
  14. kobefan234 macrumors 6502

    kobefan234

    Joined:
    May 12, 2008
    #15
    And my macbook pro charged to its fullest in 4 hours. Is this normal? or that just a trickle charge?
     
  15. OmahaGTP macrumors member

    Joined:
    Oct 15, 2008
    #16
    Quick question and I'm out, not trying to thread hijack. :eek:

    Brand new MBP (early 08 Penryn). I've been using it plugged into the charger the last few days. I'm giving the battery a whirl right now. I've been on it for about 50 minutes, and it started out with 3:14 left, and is down to 2:28, pretty good.

    But, for example, I was just watching a vid full screen on Hulu.com. A short 4 minute clip, when I came out, it said I had 1:34 left, then a minute later it jumped back to 2:28, now 2:31. Anyway, long story short, is this normal? Can I watch streaming videos for more than 15 minutes?!

    Thanks.
     
  16. mAc-warrior macrumors member

    mAc-warrior

    Joined:
    May 11, 2004
    #17
    Of course you can! The battery meter will show you time remaining under the current usage load. It takes into account total usage of the computer including graphics, screen brightness, Wifi, Bluetooth, CPU usage, etc. It will give a decently accurate readout for battery life under its current load. It takes a few minutes for it to decide what that is. If you want to try this out, dim the screen down to its lowest setting, then wait a few minutes and check it. Then crank it up to max brightness, wait a few minutes again, and check it. The battery life will be significantly shorter with the display on max brightness.

    Kobefan,

    Anywhere in the upper-90's is perfectly normal for a newish MBP. The coconut battery reading for "battery capacity" will fluctuate. My MBP is a month old -- its been down to 94%, up to 102%, and currently sits at 97%. Its not a big deal, don't obsess over it.

    OP,

    Perhaps unlike Toshiba, I don't believe that Apple specifies that you need to plug in a new notebook for such a long time. When I got mine, I plugged it in (the battery was already 7/8 charged according to the meter on the side of it) and turned it right on. It will charge as its being used. This is the way its intended. It won't cause any problems!

    --mAc
     
  17. jon08 thread starter macrumors 68000

    Joined:
    Nov 14, 2008
    #18
    I got my MBP a couple about 2 weeks ago and I'm about to do the battery calibration thing..

    However, I'm a bit confused on the 5th point: "Turn off the computer or allow it to sleep for five hours or more."

    Does this mean you either a) turn it off b) let it go to sleep for 5 hrs or more?
    Or turn it off for 5 hrs OR let it go to sleep for 5 hrs? :)
     
  18. nerdbert macrumors regular

    nerdbert

    Joined:
    Nov 7, 2007
    Location:
    Berlin, Germany
    #19
    That means you can either turn it off or you can let it sleep for at least 5 hours . At least semantically that's what it says.

    The purpose of this exercise is to collect data from the battery in every possible state (charging, full, draining, totally empty). So if you really want to make sure that the battery is flat you should put your MBP to sleep until it can't resume without a reboot (hibernation from disk). I guess 5 hours is a good estimate. You should go with b) to make sure that the battery is really empty.

    However, calibration won't make your batteries run any longer. I calibrate about 2 times a year by accident. Even if your battery is badly calibrated it doesn't run for a shorter period - it shuts off when it's close to being empty. I don't need to know whether my battery is at 15 or 10% - both values tell me that I have to find a plug rather quickly. If you calibrate too often it will just diminish battery life.
     

Share This Page