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jazzhand Level 1 (0 points)

I can leave my laptop plugged in all night turned off, and in the morning it only has 99% battery. It seems to quickly discharge. After about an hour an a half, I am down to 50%. I bought this computer in October. I has intel core i7 with 4GB 1333 MHz DDR3 memory. This does not seem normal. If it is in sleep mode, the battery will drain over night if not plugged in. That also does not seem right. I appreciate any help.


Here is the system info:

Battery Information:


  Model Information:

  Serial Number: deleted

  Manufacturer:          SMP

  Device Name:          bq20z451

  Pack Lot Code:          0

  PCB Lot Code:          0

  Firmware Version:          201

  Hardware Revision:          000a

  Cell Revision:          158

  Charge Information:

  Charge Remaining (mAh):          2908

  Fully Charged:          No

  Charging:          No

  Full Charge Capacity (mAh):          5454

  Health Information:

  Cycle Count:          35

  Condition:          Normal

  Battery Installed:          Yes

  Amperage (mA):          -1922

  Voltage (mV):          11176


System Power Settings:


  AC Power:

  System Sleep Timer (Minutes):          16

  Disk Sleep Timer (Minutes):          10

  Display Sleep Timer (Minutes):          5

  Wake on AC Change:          No

  Wake on Clamshell Open:          Yes

  Wake on LAN:          Yes

  Display Sleep Uses Dim:          Yes

  PrioritizeNetworkReachabilityOverSleep:          0

  RestartAfterKernelPanic:          15

  Standby Delay:          4200

  Standby Enabled:          0

  Battery Power:

  System Sleep Timer (Minutes):          5

  Disk Sleep Timer (Minutes):          10

  Display Sleep Timer (Minutes):          5

  Wake on AC Change:          No

  Wake on Clamshell Open:          Yes

  Current Power Source:          Yes

  Display Sleep Uses Dim:          Yes

  Reduce Brightness:          Yes

  RestartAfterKernelPanic:          15

  Standby Delay:          4200

  Standby Enabled:          0


Hardware Configuration:


  UPS Installed:          No


AC Charger Information:


  Connected:          No

  Charging:          No

MacBook Pro, Mac OS X (10.7.2), 750 gb hard drive, 4 gb ram, i7 pro
  • eww Level 9 (52,980 points)

    If the battery drains completely overnight when not plugged in, the machine is either not going to sleep at all or not staying asleep. That is not normal, and you need to figure out which is true and what's preventing the machine from sleeping. When the sleep light pulses, the machine is asleep. When the sleep light is on steadily, not pulsing, the display is asleep, but the computer is not. Before leaving the machine for the night tonight, make sure the sleep light is pulsing. Then note the light's status in the morning before you wake the computer. Post back with your findings.


    An overnight drain from full to 99% while shut down is normal, because once the battery is fully charged, charging stops, and does not resume until the battery has gradually drained to below 95%. Whenever a battery isn't being charged, it is slowly losing its charge, even if nothing is connected to it at all. This is a fundamental property of batteries.


    Battery runtime while the computer is in use depends entirely on what the computer is doing and on your user settings. The maximum battery-powered running times advertised by Apple can only be achieved if the machine is doing almost nothing and all energy-saving settings are maximized. To maximize running time on a charge, do all of the following:


    Dim the screen as far as you can stand

    Turn off keyboard backlighting

    Turn off BlueTooth

    Turn off Airport when it's not in use

    Make sure you aren't using the discrete GPU, if your MBP has one

    Disconnect all bus-powered peripheral devices: portable hard drives, iPhones, iPods, iPads, USB mice, USB trackpads and keyboards, graphics tablets, cameras, etc., etc.

    Quit all applications that aren't in active use

    Close all application windows and tabs that aren't in active use

    When using wifi, avoid web sites that have Flash content, including advertisements

    Don't use the optical drive

    Don't stream multimedia content form the Web


    If you can take all these steps and still get anything useful done, you may be able to get close to Apple's maximum running time estimate for your machine. In practice, very few of us can accomplish anything under these conditions, so we don't expect anything like maximum running time on a charge.

  • hiranyaN Level 1 (0 points)

    Download Istat Pro, its a simple widgit you can get it quite esily and free .  Dashboard > + > Manage Widgits >more widgits . This wont fix your problem but will display you battery health. Because i use my early 2011 macbook pro and when it sleeps over night i lost only about 2-3% charge so it shouldnt be a problem. But incase it shows a low battery health level then you should follow eww's advice. if it is a late 2011 laptop get it check out at the apple store because the battery should give better preformance. and on your battery icon indicator put it on the "show time" option. it gives you timly updates of about howmuch time it takes to discharge with your current usage. also hte initial drain at start up is normal i experience the same thing.


    Cheers HiranyaN

  • jazzhand Level 1 (0 points)

    Istat pro tells me the battery health is 95% and 35 cycles.






    PS: Also, my fully charged battery shows approximately 4 hours left.


    Message was edited by: jazzhand

  • eww Level 9 (52,980 points)

    And have you taken any of the steps recommended in my post above?

  • jazzhand Level 1 (0 points)


    It seems that the only way to keep the battery alive is not use the machine! I am going to have checked at an Apple store when I can get to one. The nearest one is 2 hours away. I appreciate your advice.




  • eww Level 9 (52,980 points)

    That's not really the right conclusion to draw. A more accurate one would be that if you're using your machine for anything practical that comes close to using its power and justifying its cost, you can't expect to get the maximum battery life that's claimed for it under ideal (i.e., impractically light) usage conditions, and you should adjust your expectations accordingly. Go ahead and get your battery checked if you like, but I suspect it may prove to be fine, and it's your expectations that need correcting.


    One could also argue that Apple's battery-life claims should reflect something closer to real-life performance. But who's to say what "real life" is? Watching Flash videos on YouTube for hours on end with screen brightness turned all the way up isn't unusual for many young computer users. Extended sessions of high-intensity 3D action gaming are anything but unusual nowadays. Streaming a Netflix movie is mainstream stuff. Video chatting by the hour over Skype or FaceTime is taken for granted. Gone are the days when the average personal or business computer was used mostly for word processing, spreadsheets, email and browsing the simple web sites of yore. Any of the aforementioned common usage patterns, all of which are highly demanding and were unthinkable five years ago, can flatten a MBP's battery in a couple of hours. But a different, less demanding yet still commonplace set of activities can permit the same battery to last five to six hours instead. So what figure should Apple provide to engender reasonable expectations across the whole user base? I don't think the answer is simple.

  • jazzhand Level 1 (0 points)

    I am 58 years old and have had macs since 1988. I don't play games of any kind. I do watch some programs on Hulu or amazon. I am more concerned with it draining overnight while not using it. My old MacBook seemed to hold a charge longer. Maybe my expectations are too high, but  given the way I use it, I would expect a bit more battery life.



  • eww Level 9 (52,980 points)

    To prevent the battery from draining overnight while you sleep, just plug it in.

  • jazzhand Level 1 (0 points)

    I thought it was not a good idea to leave the charger connected, preventing the battery from cycling properly?

  • eww Level 9 (52,980 points)

    As long as you run it on battery power for a few hours a week, it can be plugged in all the rest of the time with no ill effects whatsoever.

  • stefano187 Level 1 (0 points)

    Nice to know Eww, I was asking myself if it was safe. Can you quantify "few hours"? Around 10 is enough to then leave the machine plugged in?

    By the way I have a few more questions regarding battery life. I have bought a macbook pro 13" less then one month ago. The first battery was not working well, its health decreased to 69% in 2 days, so I took the mac back to the Apple store and they changed it. The new one seems to work properly according to what you guys have written. I wasn't expecting the declared 7 hours 'cause I'm using many applications while surfing the web (iTunes, Skype, Word, Adobe and I visit websites that often use flash). For the moment it lasts around 5 or 6 hours, I'm ok with it. The point is that after a week of usage, according to iStat pro the new battery has already decreased to 97% (2 cycles). Do you think it's normal and how accurate is the iStat evaluation? Second question is: is it normal to see the max. mAh capacity constantly decrease? When I got it back from the Apple Store it was at 5670 mAh, now after a week it is at 5571.


    Cheers from Italy

  • eww Level 9 (52,980 points)

    Ten hours a week on battery power is plenty to, as Apple says, "keep the electrons moving." Even three or four would be enough.


    The reported full charge capacity (and thus the "health") of the battery will fluctuate, up as well as down, by several percentage points from day to day and week to week throughout the battery's useful lifespan. It just isn't a high-precision readout, so don't obsess over it. If it falls to below 80% health and stays there before the machine is a year old, your battery will probably be replaced again.


    It sounds to me as though you have sensible, realistic expectations and a normal battery so far.

  • stefano187 Level 1 (0 points)

    Ok, good advices. It's good to know that it will fluctuate (although for the moment it does fluctuate mostly down).

  • bellaluna48 Level 1 (0 points)

    I also have issues with my late 2011 MBP battery life and find the current excusses listed just that poor excusses.  There is NO reason that my 2006 Macbook with a battery that had accourding to the Apple store out lived its use over three time, still can out perform my brand new MPB with the same tasks. 


    Old Mac book normal runtime ~7 hours (using MS office products, full brightness on my screen, and keeping multiple programs open) So don't tell my I need to turn down my brightness, don't tell me I have too many programs open. 


    New Mac book dies in 2 hours watching a video, okay maybe I will buy that the video drains it.


    New Mac book dies in 2 hours with ppt only.  Totally unexceptable.  If I wanted performance like this I would have bought a PC.  I can't even deliver a presentation.  My old mac book could run ppt for 4-5 hours straight with several other programs running in the background. 


    I'm a medical student and with my old mac book could sit through classes all day without needing a charge.  Although I usually did stay plugged in since it was all day but the point is I could do it if I needed to thus the newer computer should be better not worse. 


    I really hope there is a fix for this.  Performance is more important then having Lion so Its a no brainer for me to return my new computer in the next week.

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