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bbombf

macrumors newbie
Original poster
Oct 13, 2011
11
0
I realize this is a relatively noobish question but I figured I'd go ahead and ask for some advice. I just picked up a new 2012 MBP 13" today that I plan on using in college next year as a freshman. I was wondering what the recommendations on charging it would be so that I can get the maximum amount of battery life possible before having to replace it. I'm coming from an early 2008 Macbook which was my first Mac, and while it sat at my desk most of the time I continued to let the battery drain and then plug in at around 10% and let it fill back up again for the first couple years I had it. Obviously that's probably not the best case for this new computer seeing as I'll be getting out more with it and such. I realize batteries don't last forever but I'd like to get the best I can! Thanks!
 
There is post everywhere on this but according to apple its best to leave unplugged in for 2 days, unplug on the third day, let it get to about 50% and plug it back in.
 
There's lots of great info on lithium ion batteries here: http://batteryuniversity.com/learn/article/how_to_prolong_lithium_based_batteries
And here: http://batteryuniversity.com/learn/article/how_to_store_batteries

Bottom line:
1. Minimize the number of charge cycles.
2. Avoid deep discharges.
3. Try to keep the battery cool.
4. Try to store the battery partially charged (40%) when not in use.

The first two conditions can be met by leaving the laptop plugged in when possible. It's pretty hard to meet the last two conditions with a non-removable battery.

With my older MBP, after my first battery got weak and was replaced, I continued to use it for normal use when the laptop was plugged in, and the battery was at full voltage and often hot. I would keep a partially charged "good" battery in the fridge ready for use when traveling. I got about 18 months out of the first battery and my "reserve" battery is still in good shape after three years.

With my new rMBP, about all I can do to prolong the lifetime of the battery is to leave the laptop plugged in when possible and put it to sleep as much as possible to keep the machine and the battery cool.
 
You want the electrons to keep moving. Apple recommends to not have it plugged in all the time. Okay to discharge completely and then charge fully, in fact you should do this once in a while.

personally, i have mine plugged in and completely discharge once in a blue moon. I have used 481 cycles and have 91% battery health (istat pro). still get 6-8 hours depending on my usage.

don't worry too much about the battery life. it is rated for 1000 cycles with at least 80% battery health. mine will last 4-5 years at this rate.
 
Run on battery whenever you need to and plug it in whenever you can. You can plug or unplug at any time, regardless of the charged percentage. Just make sure you don't run on AC power all the time, as your battery needs to be used regularly to stay healthy.

There are many factors that impact your battery life. See the BATTERY LIFE FROM A CHARGE section of the following link for details, including tips on how to maximize your battery life.

This should answer most, if not all, of your battery/charging questions:
 
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