One year old 2012 MBA poor battery health?

Discussion in 'MacBook Air' started by coldjeanzzz, Feb 7, 2014.

  1. coldjeanzzz macrumors 6502a

    Nov 4, 2012
    I don't understand what is happening. I have noticed for a while now that I do not get the 7.5 hour advertised battery life on my 13 inch 2012 MBA. I'm lucky to get 6 even with less than 50% brightness and very little flash and no intensive apps open

    The Battery Health app showed the health at 87% a week ago which was already bad in my mind and now it's at 82.8 today. I have been regularly unplugging it over the last month as I was worried I wasn't taking it out enough. I have already tried calibrating it even though this is supposed to be unnecessary for newer Macs. I only have 109 cycle on it too so this battery health seems extremely poor. Its only a couple of percent away from that 80% 1000 cycle mark which I am not even close to approaching.
  2. 77slevin, Feb 8, 2014
    Last edited: Feb 8, 2014

    77slevin macrumors member


    Feb 21, 2013
    Try Coconut

    Never mind, I didn't read all of you post. Please ignore.
  3. GGJstudios macrumors Westmere


    May 16, 2008
    First, Apple does not say you will get 7 1/2 hours of battery life. They say "up to" 7 1/2 hours. There are many factors that impact your battery life. See the BATTERY LIFE FROM A CHARGE section of the following link for details, including tips on how to maximize your battery life.

    It is perfectly normal if your battery health (maximum capacity) is more or less than 100%, even when brand new, or if it fluctuates up or down over time. The gradual decline is not in a straight line downward, and it may decline more rapidly at some times and slower at others. For further details, read the CHECKING STATUS AND HEALTH section of the following link.

    The built-in batteries in the newer Mac unibody notebooks come pre-calibrated and do not require regular calibration like the removable batteries in older Apple notebooks. Calibrating will not improve your battery's health.

    If your battery health drops below 80% before 1000 cycles and it's still covered by warranty or AppleCare, take it to Apple.

    The link below should answer most, if not all, of your battery/charging questions. If you haven't already done so, I highly recommend you take the time to read it.
  4. kage207 macrumors 6502a

    Jul 23, 2008
    This. I agree with a lot of what you say.

    Though there is one thing I disagree with. Most people say the battery does not need to be calibrated. This is part is true, it doesn't need to be. There's a big but to this statement. It's important to 'exercise' your battery about once a month. This means draining the battery all the way down to keep all electrons moving in the battery.

    My battery is at 87% health at 251 battery cycles. It was down to 83% when it was at 200 cycles. This fluctuates all the time. Don't be concerned. Keep it plugged in as much as you want. Just exercise it once a month to keep the electrons moving.

    I do get roughly about 7-9 hours of battery life on my MBA (note not always constant use). What apps are you using? Look at coconut battery every once in awhile because it will tell you how many watts you are using.

    You also aren't tell us how you are using your computer which a lot of things can affect battery performance.
  5. GGJstudios macrumors Westmere


    May 16, 2008
    It's not that most people say the battery doesn't need calibration. It's the fact that Apple states that clearly. No, it is not necessary to fully drain the battery, and doing so is not recommended. That is not required to exercise the battery. People frequently misunderstand and misquote Apple's statements regarding this.
  6. kage207, Feb 9, 2014
    Last edited: Feb 9, 2014

    kage207 macrumors 6502a

    Jul 23, 2008
    Do you understand the science of batteries? Also, I do not misunderstand Apple at all. Here is a direct quote from Apple.
    EDIT: Also know that calibration is so that the software 'unit tests' the battery to see how it is actually preforming against the software metrics. This is not needed in the newer models. You are correct about this. This however does not keep the electrons flowing.

    EDIT 2: Also, I say most people for a reasons. Those that know what they are talking about and leaving room for the exception. This is not a misunderstood statement at all. This is actually what I've learned from Apple's education for retail. I used to work at the Apple store and know what I'm talking about as I've been trained. Not trying to start a fight, I'm trying to make sure correct information is given.
  7. GGJstudios macrumors Westmere


    May 16, 2008
    I'm quite familiar both with battery science and with that quote, as demonstrated in thousands of my posts over the past 6 years.

    I never referred to calibration as a recommended method of keeping electrons flowing. As I've stated thousands of times, calibration serves to make battery readings more accurate, not to affect the health of the battery. I think you may have misread a post somewhere.

    It is not correct to claim that exercising the battery requires fully draining it, and that quote from Apple does not state otherwise. That is the part of the quote that is frequently misunderstood or quoted out of context. You can exercise a battery by draining it to 20% or 50% or 70% or any other percentage and recharging enough times to make a cycle or more. You never need to fully drain newer Apple notebook batteries in order to keep them healthy. This is evidenced by Apple's statement:
    You'll notice it doesn't say that an ideal use would involve fully draining the battery once per month. This is because exercising the battery does not require fully draining it.
  8. lagisibuk macrumors 6502

    Jun 25, 2013
    Always Somewhere
    I have a 2010 MBA and battrey health is 87%,
    battey health is depend on many factor, like how u charge this battrey.

    i'm using MBA 15 retina, and is 1 year now... battrey health is perfect :D

Share This Page