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Watts and my MacBook Pro’s Battery

I downloaded an application called "Watts" from Binary Tricks because I was hopeful it might help me to solve an issue I've been having with my MacBook Pro.

Basically, my battery will get to about 75 or 78 percent or so, then shut down. Not go to sleep - just die immediately and without warning.

I had hoped that Watts would let me recalibrate the battery. Originally my battery status was "healthy." I'd completed 17 charge cycles out of about 300. The battery retained 96% of its capacity.

After running Watts through one of the "shutdowns at 75%" it now tells me my battery needs serviced and lists the capacity at 52% (2947 mAh out of 5600).

It appears I'll have to take the computer to an Apple store (I'm heading to the nearest one in Buffalo in a few days). Any tips or tricks? What's up with the battery?

8 Responses to "Watts and my MacBook Pro’s Battery"

  1. If you've only run it thru 17 charge cycles, you should have no problems getting Apple to replace your battery. They're usually really good with battery defects.

    Connor P

  2. I had a similar thing happen to a 4 year old MacBook Pro that already had its battery replaced once. My local Apple store hooked it up to an iPod running some diagnostic tool and then replaced it for free.

  3. Replaced the battery, that is. 🙂

  4. When I had battery/charge issues, resetting the PMU solved my problem.

  5. [quote comment="62369"]When I had battery/charge issues, resetting the PMU solved my problem.[/quote]

    I've reset the SMC a few times. No dice.

  6. Yea, that 🙂 I forgot which was the new thing and which was the old. Sounds like it's off to the Apple Store for you. 🙁

  7. Your battery most likely has a defect. When I was researching on getting a new battery similar users with your symptoms got them replaced by AppleCare or just talking to the genius bar. Hopefully you luck out.

    If they don't offer to help you, you can always purchase a battery.

  8. This may be elementary, but laptop batteries are made of several independent cells, which can fail independently. Unfortunately, they don't tend to realize a cell has died until they switch to it for power - and your computer dies. I had the same thing happen on an old MacBook Pro battery, which died at 30% remaining exactly as you describe.

    Sadly, all you can really do is replace it. It's not like "normal" capacity loss where the cells simply hold a bit less juice - the cell failed entirely. Resetting things Mac or even battery side isn't going to stop it from using the dead cell, and as soon as it does, your computer will die.