Click the links above. The 50% is straight from apple. Not sure why you got all defensive in this thread. relax man.
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rMBP Battery Health Decline
- Thread starter charlieegan3
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Click the links above. The 50% is straight from apple. Not sure why you got all defensive in this thread. relax man.
Your recommendations are fine, except this one. You don't want the battery to stay at any certain percentage. The battery needs to be exercised to stay healthy. Rather than try to keep it at a certain level, just use it normally. In the process of using it normally, you may drain the battery down to 80%, then recharge to 100%, then drain to 45%, then charge to 78%, then drain to 30%, then charge to 90%, etc. (as an example).
I'm calm. I would just rather people post facts rather than conjectures. Also, I read those links and that's why I'm surprised that so much hogwash is being posted here. Concerning the 50%, here is what Apple says:
Notice the conditional that I bolded for you, if you run it plugged in most of the time.... That doesn't apply to those who run it unplugged most of the time.
These are the same types of batteries as in the iPhone and iPad. Why aren't you recommending people only use their iPads and iPhones to 50%?
Just general info I've picked up around the Internet from researching this topic ages ago when I first purchased an iPod touch. There's a lot of fluff out there on this topic, but constant themes out there repeat that it's harmful to fully discharge these batteries (some have implied that <20% is bad), and that you should keep the battery "exercised" without stressing it too hard, hence trying to keep the charge very loosely around middle-ish without violent swings from 0% to 100%.
I've yet to find a consice, referenced, detailed writeup on the whys and wherefores of this, and I'd love to know some of the chemistry involved.
Assuming it's an equilibrium reaction that releases electrical energy by the conversion of Li to Li+, then it makes sense to hover around 50% charge to maintain equilibrium, especially when in storage, and it also makes sense that fully discharging damages the cell.
But then again, like I said, I've never seen a good writeup.
System Profiler > Hardware > Power > Battery Information
Or, install iStat Pro to quickly check stats on battery, temperatures, fans, drive usage, CPU usage, uptime, etc.
That varies from one model to another. iStat Pro will give you the percentage remaining.
Thanks. Though sadly there is no hard data (not your fault), the post is very informative.
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What model do you have? My base model, 2.3 ghz, 256gb, and 8gb RAM had ~8760 on cycle 1.
I have the 2.6/8/512
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There is definitely fluctuation in the battery capacity.
Just sitting here with coconut battery open it has gone from the figure I previously posted, to 8574, to 8550, to 8574, to 8594.
These battery readings seem to be only good for ballpark (at best) ideas of if your battery has taken a large percentage hit in capacity.
While the batteries don't like to be fully discharged, it won't hurt to occasionally do so if your normal needs require it. There is no truth to the implication that draining or charging outside the middle range is bad.
I think you've confused normal daily use with storing a battery. Apple does recommend storing a battery (for 6 months or longer) with a 50% charge. However, that has nothing to do with normal use.
Read the Battery FAQ I posted.
Yep, that's a good idea. Your battery is likely to die quicker if you leave it plugged in all the time.
I would say it is normal. The battery will probably fluctuate until it gets "settled in" so to speak. All of my batteries in the past from apple seem to do this. Including replacements from 3rd parties. My wife never followed proper charging on her old gateway laptop from 2005 and it still holds a usable charge to this day.