Mountain Lion

I downloaded Mountain Lion, and all went well. My computer seems to be running faster , but i have noticed that my battery drains faster. I almost always have my computer plugged in, so it's normally at 100%. I did unplug it, and it went to 99% pretty fast, so i plugged it back in, and have kept it plugged in for two days now, and it still will not go back to 100%. I'm concerned that this could be something permanent, or damaging to my battery.

I highly doubt any physical damage was done to your battery. What you're likely seeing is that your SMC (Systems Management Controller) is re-learning your batteries trending data.

Personally, I would unplug it, use the machine as you normally would, but completely on battery. Allow it to fully drain until it goes to sleep on its own. When it finishes, allow it to fully charge. Chances are, that alone will clear up the problem of seemingly fast battery consumption, and also the charge level not showing 100%.

I would also recommend reading this article, so you understand how to maximize the usefulness of your battery:

Apple - Batteries - Notebooks

Thank you for the information. Is it bad to use my laptop plugged in all the time, because 95% of the time I use it while it's plugged in.

confussedbrenda said:

Thank you for the information. Is it bad to use my laptop plugged in all the time, because 95% of the time I use it while it's plugged in.

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I don't believe so, but it may be less than optimal. Your battery is meant to be used and occasionally drained. With that said, in my professional life, I've supported hundreds of laptops that were kept plugged in 95% of the time, and their batteries had good long lives.

confussedbrenda said:

I did unplug it, and it went to 99% pretty fast, so i plugged it back in, and have kept it plugged in for two days now, and it still will not go back to 100%. I'm concerned that this could be something permanent, or damaging to my battery.

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This is VERY normal. I cannot find the Apple link at the moment (but I read it recently)...where Apple laptops are designed/programed to NOT charge the battery until it falls below 95% (or there about). This is to minimize the amount of unnecessary short duration charge cycles.

If you REALLY want to experiment with what I'm saying. Simply unplug your laptop...let the battery charge drop below 95% (or even down to 90%)...then plug it back in...and I can almost guarantee you that it will start charging.

It's just between the charge levels of 95-99% where the battery will not automatically charge back to 100%.

HTH,

- Nick