7 Hour Battery Life ???

Discussion in 'MacBook Air' started by BWhaler, Feb 3, 2008.

  1. macrumors 68000

    While I purchased a MBA (coming mid February) I have been concerned about the lack of swappable battery given I take long international flights.

    I stopped by the Apple store today, and did my "airplane battery test."

    I unplugged the MBA, turned off all wireless and dimmed the screen all the way down to 2-3 notches, and the battery meter said 7:08 hour remaining.

    Over 7 hours. Wow.

    Now, I fully understand even in the best case, this would mean 6:30 when actually using it.

    And of course, on the ground with the screen brightness turned-up and wireless on, I assume I would see between 4-5 hours.

    But the fact that there is a good shot to use the MBA on cross-country flights gives me hope.

    Now, don't get me wrong, I would love a swappable battery. But hopefully this is some good news. I'll know in a few weeks.
  2. macrumors regular

    You can usually always extend the battery life by dimming the screen way down. I know I used to do a lot of work at night on my laptop, and with the screen turned way down to one bar (so as not to destroy my eyes), I got killer battery life out of it. They just don't expect people to run the computers all the time under those conditions, so they can't give estimates based on a dim screen.

    In general though I think their battery estimates are always too high.
  3. Moderator emeritus


    I'd love for you to be right, but I think your test is flawed in that new computers have notoriously bad battery calibrations. There have been a few reviews already that all peg the battery life as what you'd expect based on Apple's promise -- that is, you can get around what they said (in the 5s, right?) if you optimize, and you can get in the high 3s or perhaps low 4s with fairly "robust" use (as you describe it, wifi on, reasonable brightness).
  4. macrumors 68030

    I just unplugged my Macbook Pro from the mains and it said 212 hours. So if you really want decent autonomy ditch the MBA and go with the tried and trusted MBP.

    Of course, after a minute or so, it will change its tune and say something else entirely.

    My Macbook battery has had nearly 100 cycles and is still showing 100% of original capacity. The battery on my Macbook Pro is already down to 90% after a mere 20 cycles (and it is overstating those, if anything).

    Mac OSX battery indicator = extension of Jobs's RDF.
  5. Moderator emeritus


    I'm curious if this changed with the move to Intel hardware... it's not very realistic to expect that you're truly at 100% of original capacity after 100 cycles. You should be in the 90s probably, but not 100%. And my PPC macs were always rock-solid accurate in their battery estimates. Although, I guess, in those days even there were the ones that would shut down when they had 20% battery life or something like that.
  6. macrumors 68000

    All great points.

    Here's why I am excited about the possibility of the MBA battery life:

    To get my MBP to be anywhere near what Apple promises, I have to have to turn everything off. (Airplane mode) as I call it.

    With the MBA, it looks like the 5 hours is the expected normal time, and in "Airplane mode" it gets even more than 6 hours.

    Again, I am not sure, just a quick experiment. And being a global traveler, I know as well as anyone how much Apple flat-out lies about battery life.

    But I think change may be in the air. The latest iPods have battery lifes closer to their claims. Maybe Apple has decided to be honest about this--maybe, just maybe--and give us real world ratings.

    Well, I'll know in a few weeks.
  7. macrumors 603

    NC MacGuy

    I'm testing mine as I write.... So far on two cycles I've had 4:38 min & 3:57 min. The lower one was while I was trying to run Disk Utilities, it was cranking and the fans were going max. The current run was started at 6:28 pm w. airport on and active web surfing, word used about 40 min and itunes running in the background. I have 22% battery left. This kicks both my MB & MBP's butts battery-wise but they are both older but I typically get 2:30- 3:30 out of them doing nearly the same tasks.
  8. macrumors 603

    NC MacGuy

    Third run 4:21 minutes using airport w. itunes, word and display fairly bright.

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