Another Battery Charging Question

lazer155

macrumors regular
Original poster
Jul 5, 2010
150
0
I've been looking around for the last couple days for information about how often to take the rmbp and cmbp off the charger and how low to discharge them before plugging them back in. I found several threads here, on google, and in the apple support forums.

Here are some of the articles that I read:

http://www.apple.com/batteries/notebooks.html
http://www.bigbruin.com/2007/battery_1
http://www.apple.com/batteries/
http://docs.info.apple.com/article.html?artnum=86284
http://batteryuniversity.com

http://batteryuniversity.com/learn/article/how_to_prolong_lithium_based_batteries

The problem is that none of these articles or the other threads I found on this forum actually give a number for what percentage you should let the battery reach before plugging it back in to recharge. I will mainly be using my rmbp as a desktop. Because of this I will be able to keep it plugged in most of the time but I know that without being used, the battery will degrade more quickly.

This is the only apple discussion support post that I could find that mentioned a percentage but it wasn't given by someone at apple:

https://discussions.apple.com/thread/4185138?start=0&tstart=0

What percentage should I let it run down to before plugging it back in?
 

sweetbrat

macrumors 65816
Jun 17, 2009
1,443
1
Redford, MI
There's no right or wrong number. Unplug it when you need to be portable, plug it back in when you can. If you're plugged in almost all the time, which it sounds like you will, run it off the battery for a while a couple times a month to exercise it. There's no magic number to run it down to.
 

lazer155

macrumors regular
Original poster
Jul 5, 2010
150
0
Whenever you have access to plug it in again. There's no right or wrong number. Unplug it when you need to be portable, plug it back in when you can. If you're plugged in almost all the time, run it off the battery for a while a couple times a month to exercise it. There's no magic number. Just use your computer the way you need to.
Do you think it would be better to go down to 25% once a month or do 75% 3 times a month? Or do you think a drain to 90% once every few days is best?

I agree though, there really doesn't seem to be a definite number. Just general guidelines of use it on battery when you need to. That's kind of a problem for user like me who don't travel a lot and always have a plug available.
 

Bryan Bowler

macrumors 68040
Sep 27, 2008
3,765
3,444
Don't read too much into it. Just keep the electrons occasionally flowing in the battery and you'll be fine. In other words, whether you go to 25% or 75% doesn't really make any difference...but you do need to get the battery moving every so often. Whether that's once a week or once every two weeks doesn't really matter all that much either.

Bryan
 

lazer155

macrumors regular
Original poster
Jul 5, 2010
150
0
Don't read too much into it. Just keep the electrons occasionally flowing in the battery and you'll be fine. In other words, whether you go to 25% or 75% doesn't really make any difference...but you do need to get the battery moving every so often. Whether that's once a week or once every two weeks doesn't really matter all that much either.

Bryan
Alright, I'll do that. Maybe discharge to 75% every three weeks. I just wish apple would give a slighty more specific recommendation for what discharge percentage is enough to keep the electrons moving.
 

GGJstudios

macrumors Westmere
May 16, 2008
44,419
759
I've been looking around for the last couple days for information about how often to take the rmbp and cmbp off the charger and how low to discharge them before plugging them back in.
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. There is no right or wrong frequency or 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.

Also, rather than get generic battery information from various sources, it's better to get battery information from Apple, since they made the battery and are liable to replace it if it's defective.

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