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macmee

Suspended
Original poster
Dec 13, 2008
835
1,110
Canada
I have a 15" MBP I got around Christmas. Right now I unplugged the battery and it's at 94% which is 5265 mAh (cycle count is 9 condition normal).

I've Googled whether I am ok to always leave it plugged in all the time, if I should do full discharges or if I should do small discharges. I've seen a lot of people who never used their battery for 3 years and it's still going strong, and I've heard stories of people doing regular discharges and batteries only lasting 4 months.

My question is, to maximise the life of my battery should I:
- always keep AC plugged in whenever possible
- do FULL discharges from like 100 to 10 percent once a week/month
- do small (like 10%) discharges once a week/month

Thanks :D

edit: it says full charges are 5473 mAh, shouldn't that be 5600 :(
 
I have a 15" MBP I got around Christmas. Right now I unplugged the battery and it's at 94% which is 5265 mAh (cycle count is 9 condition normal).

I've Googled whether I am ok to always leave it plugged in all the time, if I should do full discharges or if I should do small discharges. I've seen a lot of people who never used their battery for 3 years and it's still going strong, and I've heard stories of people doing regular discharges and batteries only lasting 4 months.

My question is, to maximise the life of my battery should I:
- always keep AC plugged in whenever possible
- do FULL discharges from like 100 to 10 percent once a week/month
- do small (like 10%) discharges once a week/month

Thanks :D

edit: it says full charges are 5473 mAh, shouldn't that be 5600 :(



No its not a great idea to leave it always plugged in
 
I think that they automatically cycle (between 95% and 100%), so you can leave it plugged in. This would certainly be in Apple's interest, as it saves them money replacing dead batteries!

This is I believe the case with iPad 3 (not sure about iPad 1 or iPad 2).
But to be on the safe side why not simply follow Apple's advice on the matter.

http://www.apple.com/batteries/notebooks.html
 
I was just listening to the MacCast podcast, and Adam (the host) was talking about how he has used laptops as desktop computers (kept them plugged in all the time) and the batteries usually die after 2 years of use.

From what I heard on the show, i'd advise charging to 100%, then letting it drain to around 30% and charging to 100% again and so on. If you need to store your computer for a while, charge it to 75% (this is what Apple does).

What I used to like doing on my old Windows laptops was to take the battery out of the laptop and just keep it on the mains when I was using it as a desktop, but I don't think you can do this very easily/at all on MacBooks (I've never had one).
 
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