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Pablo90

macrumors member
Original poster
Aug 21, 2010
85
15
Hi guys, I was wondering about how to preserve my battery as long as possible...

I just bought the new MBP 13" 'cause I'm gonna need it for college, but since I'll also use it as "personal computer", for web browsing, playing music and movies, I'll probably have to charge every day...

My question is: if I got home and my MBP is dead, I plug it in and use it, when the battery is fully charged, I have to unplug it or I can use it for the night (still plugged in) and just unplug it the next day for school?

Is it somehow harmful to my battery life?

I called the Apple assistance and they told me that I need to discharge the battery at least a couple of time or three a week, but that doesn't quite answer my question... I think it's some kind of "covering our a*s" thing...

And by the way, I've read that "discharge the battery" means just use at least until the 50%, is that right? So if I charge it just when it's about 40%, I just need to recalibrate once a month, and that's all fine, right?

Thank you in advance, Paolo.
 
I'm gonna give you the skinny, because this has been posted a few times on the forum.

If you can, leave it plugged in, even if it's full.

Apple recommends you 'cycle' the battery once a month or so. So just run it until it goes to sleep, then charge it. If you use it out and about, then you don't really need this.
 
There are MANY, MANY threads with your exact question. Please, before posting, try searching MRoogle.

Leaving your computer plugged in all the time isn't a problem. You should calibrate your battery once a month though. Follow the steps below to do this.

1. Fully charge your MacBook, and leave it plugged in for 2 hours. You can use it during this time
2. Unplug your MacBook, and let it discharge. Again, you can use it during this time
3. When running low on battery power, the MacBook will display a message. At this time, save your work.
4. Let the MacBook sleep for 5 hours or more.
5. After 5 hours are up, plug it back in.

I've left my computer plugged in every day since I got it in December. I calibrate my battery monthly, and I still get ~7 hours out of my MacBook.
 
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This should answer most, if not all, of your battery questions: Apple Notebook Battery FAQ

Apple on notebook batteries
Apple Portable: Calibrating your computer's battery for best performance
Laptop Battery Guide
 
As sammich and ideal say- that's the way to go. You can add a reminder in iCal so you can remember to do this once a month. It is easily done either thru iCal or go to apple web site, search batteries and click on the care of battery file. In it is a link to setting this up in iCal.
 
I'm gonna give you the skinny, because this has been posted a few times on the forum.

If you can, leave it plugged in, even if it's full.

Apple recommends you 'cycle' the battery once a month or so. So just run it until it goes to sleep, then charge it. If you use it out and about, then you don't really need this.

I do this when my battery's low...but why's my battery health at 92%? It just keeps going down, whenever I use my mbp off the charger, I'll kill the battery (making to 0% or sleep) then fully charge my battery. Why does my battery health decrease?
 
Thank you so much to everyone of you ;)
You've been very helpful and quick :D

Bye!
 
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