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Of course a new battery is almost certainly better than an old one. That's not what I'm asking about. I used the same battery in my Mac for five years but it sucked from day one really, only lasted 1.5h maximum in the beginning.

See for instance this related question where I wonder why all of a sudden my battery cycle count is too low to be true.

So I bought a new fresh one the other day and it last more than 5 hours!!! I am really surprised by this.

So there are three cases:

  1. I was really unlucky with the first battery.
  2. I am really lucky with the second battery.
  3. I was unlucky with the first battery and lucky with the second battery.

My question is: have the battery technology improved for the late 2008 unibody aluminum (and if so how?) and/or is one of the cases a,b,c true?


The batteries look identical with same numbers printed on their backside. The new one holds some 4300 mAh. The old one I don't know really since it's out of the computer now, but if I recall correctly it was about the same.

I think the difference between ~1h and ~5 hours is dramatic and I was (of course) very positively surprised.

share|improve this question
Do the two batteries have the same capacity ? (mAh) – Matthieu Riegler Dec 9 '13 at 23:57
It's hard to say anything about this when you don't post the actual model identifier of your laptop. Mine for example is MacBook Pro 5,3 or mid-2009 MacBook Pro. You can look it up by going to the Apple logo in the menu bar -> About this Mac -> More info.... – Saaru Lindestøkke Dec 9 '13 at 23:57
It's also difficult to quantify battery performance since it depends so much on computer usage and installed software - for example, have you upgraded your OS? Do you leave Wi-Fi and Bluetooth on all the time or toggle them as needed? Etc. – da4 Dec 10 '13 at 17:07
I haven't changed anything but the battery. – Faq Dec 10 '13 at 17:15
Then you probably had a bad battery before and a "good" one now. – Matthieu Riegler Dec 10 '13 at 17:52

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