1. Welcome to the new MacRumors forums. See our announcement and read our FAQ

MacBook Air Battery

Discussion in 'MacBook Air' started by dwc, Feb 9, 2008.

  1. dwc
    macrumors newbie

    Ready to return 'Air'...........really frustrated with battery recharging issue.
    Tried everything suggested in this forum.

    My MBP will completely recharge within a couple hrs., I realize power adapter is smaller for 'Air' but, come on, can't keep doing this everyday.

    Have appointment this p.m. @ store. If not resolved, ready to return!
  2. macrumors 6502a

    Not following you - if it completely recharges in a couple of hours - what were we expecting?
  3. macrumors regular


    Care to explain a bit more of your problem... Because, if your MBA recharges in 2 hours, that's excellent! Mine takes about 3~4 hours to charge 100%.
  4. macrumors 68040


    Mine too which is good
  5. dwc
    macrumors newbie


    My MBP will completely recharge within a couple hrs., I realize power adapter is smaller for 'Air' but, come on, can't keep doing this everyday.

    MBPro..........will completely recharge within a couple hrs. NOT the 'AIR'
  6. macrumors 68040


    My air charges in3.5 hours from empty......
  7. macrumors 603


    My first charge, after complete discharge (so this is the "cal" cycle), took >6 hrs (not sure total, as I went to sleep before it was done).

    I wasn't too worried about it, but reading some still had extremely long charges on subsequent cycles, I decided to do a quick test.

    I ran the battery down to 50% of capacity (showed a bit more than 4800mAh), playing YouTube videos, and music, while screen sharing.

    It ran [on battery] for 1:20 (to 50% capacity), so that's not too unexpected considering the type of use.

    Plugged it in, and the recharge time settled in on 1:30, from about 50% full. This seems about right, to me.

    Update -
    After about an hr, I checked back (using screen sharing - MBA running during charging). Now it was showing 1:40 to full charge, from 83%. I checked the charge rate, and it was down to 0.5A. So, it looks like it goes to low rate sooner (% wise) than I've seen with the MBP. Just running the MBA takes that, or more, so it makes sense the total charge time will increase noticeably after switching to low rate (typical of any machine, though).

    It looks like this will be normal for the MBA. Now, it's been sleeping for about 20 min. Woke it up to check remaining charge time and it reduced by 40min (about an hour left). If I leave it sleeping, it'll no doubt be finished much less than that.

    I think what people are seeing are charge times running vs. sleeping/off. The 45W supply just can't keep up the higher rates and also provide the overhead to run the machine. All machines will charge faster sleeping or off, but the difference is going to be more apparent with the MBA. I suspect they want to keep the internal component power levels down (temps - maybe smaller gauge wiring, traces, and components themselves).

    I haven't seen any posts from anyone trying the 65W supply, but I'm going to guess the times will be the same [as the 45W]. The charge system should limit current, so it doesn't matter if you have a bigger supply.
  8. macrumors regular

    I too am experiencing the fast discharge times, but more importantly the extremely long recharge times. In about 6 battery cycles so far, my recharge times have all been in the 4+ hours to completely recharge from 0%. Ive even been using the "battery conditioning technique" mentioned on this forum. I wait about 4 hours after the battery completely depletes before I fully charge it. Once it starts receiving external power, I do not remove the power source until the light turns green (full charge).

    I am guessing the long recharge times is due to the 45w power adapter and not a faulty battery. Does anyone know if the charger from the MBpro can be used on the air? this is going to be my next shot. Otherwise, I may seriously consider getting rid of the air.
  9. macrumors 6502

    Mine shows "4:31 until full" from 50%. That is not good.
  10. macrumors regular

    Just calibrated and plugged in a couple hours ago. I woke the computer up from sleep and it shows 80% to go until full charge with 2:20 expected for the full charge. Calibrating works!
  11. macrumors 6502a

    Also a thing to note, once you have some of the bugs tweaked like overheating and fans, your battery will last a lot longer before needing a charge.

    Play around with restarts, SMU reset and adapter plugged in or not. A good sign for when you have succeeded is when the time to charge number seems to be accurately moving along.

Share This Page