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Dcuellar

macrumors regular
Original poster
Feb 24, 2010
245
6
I was wondering if leaving my laptop plugged in is alright or should I stay away from doing that? Are there any confirmations that it does or does not hurt your battery life?

I tend to just leave it plugged in, but if it's proven to hurt the life of the battery I will change my habits.
 
I was wondering if leaving my laptop plugged in is alright or should I stay away from doing that? Are there any confirmations that it does or does not hurt your battery life?

I tend to just leave it plugged in, but if it's proven to hurt the life of the battery I will change my habits.

From what I've heard, from the forums and such, it's best NOT to leave it plugged in all the time. Try to unplug it, even if you are at your desk. It helps the battery cycle and such.


I wouldn't be too paranoid about it, just use it how you prefer.
 
Battery

I was wondering if leaving my laptop plugged in is alright or should I stay away from doing that? Are there any confirmations that it does or does not hurt your battery life?

I tend to just leave it plugged in, but if it's proven to hurt the life of the battery I will change my habits.

This is also something that I have been wondering about. I have always received conflicting answers to what is best for the battery life.
 
I haven't found any information yet.

Logically, I don't see anything wrong with leaving it plugged in. Battery life is affected when energy is taken and placed back. When you leave it plugged in, the battery is bypassed (assuming it is charged).

You don't accumulate cycles when it is plugged in and fully charged.
 
I was wondering if leaving my laptop plugged in is alright or should I stay away from doing that? Are there any confirmations that it does or does not hurt your battery life?

I tend to just leave it plugged in, but if it's proven to hurt the life of the battery I will change my habits.

You should leave it plugged in. There will be no damage done by doing so. The computer has its own charging circuitry to prevent overcharging.

The reason so many people think it's bad is because of misinterpreting Apple's suggestion of running down battery every once in a while. The reason to run the battery down is to calibrate the software battery meter. If the battery is not used often, the battery meter gets out of sync with the battery's charge state. For this reason, it's good to use the battery once in a while.

Leaving the computer plugged in (and lever running the battery down) simply causes the battery meter to become inaccurate. Running the battery down recalibrate the meter. Constantly running the battery down and recharging it simply reduces the battery's life.

Steve
 
You should leave it plugged in. There will be no damage done by doing so. The computer has its own charging circuitry to prevent overcharging.

The reason so many people think it's bad is because of misinterpreting Apple's suggestion of running down battery every once in a while. The reason to run the battery down is to calibrate the software battery meter. If the battery is not used often, the battery meter gets out of sync with the battery's charge state. For this reason, it's good to use the battery once in a while.

Leaving the computer plugged in (and lever running the battery down) simply causes the battery meter to become inaccurate. Running the battery down recalibrate the meter. Constantly running the battery down and recharging it simply reduces the battery's life.

Steve

I see your point about misinterpretation and I think you are partly right, but I believe your post is contradicting Apple's recommendations:

Apple said:
For proper maintenance of a lithium-based battery, it’s important to keep the electrons in it moving occasionally. Apple does not recommend leaving your portable plugged in all the time...

See http://www.apple.com/batteries/notebooks.html
 
It is recommended to go through at least one cycle per month to keep the battery good. As simple as that.
 
I see your point about misinterpretation and I think you are partly right, but I believe your post is contradicting Apple's recommendations:

Originally Posted by Apple, Inc.
For proper maintenance of a lithium-based battery, it’s important to keep the electrons in it moving occasionally. Apple does not recommend leaving your portable plugged in all the time...

See http://www.apple.com/batteries/notebooks.html

Apple's recommendation in this regard are useless, or at best unjustified. "Keeping the electrons moving?" Science fail.

I've had laptops that have remained plugged in more or less all the time and they've been fine. I've had laptops that cycle once every 1-2 days and they've been fine also. Just use your machine in the way that's most convenient for you.
 
Apple's recommendation in this regard are useless, or at best unjustified.

Right, sooooo we're to assume that you, Random Internet Guy, know more than Apple does about their batteries. Do you have an EE or something to back up your assertions?

"Keeping the electrons moving?" Science fail.

Generally, when one discharges a battery, electrons are in fact, moving.

http://en.wikipedia.org/wiki/Electric_current

Or, are we to blindly trust that you, Random Internet Guy, also knows more than practically all contemporary physicists out there, too?

For me the bottom line is this: I'm going to go with Apple recommends because ultimately, they made the laptop and they're the ones that will either fix a bad battery or raise a stink that it wasn't used properly. When my laptop has "miles01110" on the bezel, then I'll follow your recommendations.
 
Leaving it plugged in will kill you battery faster than plugging it about half the time. Just maybe unplug it at night, and whenever you remember to do it while using it. The batteries last a long time an give you sufficient warnings when it is running low.
 
Right, sooooo we're to assume that you, Random Internet Guy, know more than Apple does about their batteries. Do you have an EE or something to back up your assertions?

What good does me saying I have an EE degree do? As if you'd believe me. Don't fool yourself- you've already made up your mind on this one.
Generally, when one discharges a battery, electrons are in fact, moving.

Generally electrons are always moving.

http://en.wikipedia.org/wiki/Quantum_mechanics

Do what you want. I've satisfied my curiosity with experiment and have concluded that any "gain" in battery life you might get from enslaving yourself from an unnecessary calibration schedule far outweighs the inconvenience of doing so.
 

"Movement" is harder to define if you are thinking about things in terms of quantum mechanics. Electrons no longer have a position and a momentum. dP(x)/dt or dP(xbar)/dt would be the things that might change. But, not all quantum electrons have to be moving according to these definitions. Although, in a battery, the conduction band electrons would be. The inner electrons would still be in roughly stationary states. :)

I tend to agree with your take on charging though.
 
What good does me saying I have an EE degree do? As if you'd believe me. Don't fool yourself- you've already made up your mind on this one.

What a pity you are posting on the internet instead of building batteries for apple :rolleyes:
 
Well I have a 2007 macbook that has 979 loadcycles and is still at 95% health. I let it charge completely then I unplug it and plug it back in when it gives me the warning. Occasionally i leave it plugged it.

It works for me.
 
Well I have a 2007 macbook that has 979 loadcycles and is still at 95% health. I let it charge completely then I unplug it and plug it back in when it gives me the warning. Occasionally i leave it plugged it.

It works for me.

Yeah. Probably better to let it drain every month. I have a 2007 Macbook Pro with 48 cycles on it. 82% battery health. Calibrated it two days ago. I leave it plugged in a lot and not really in use (use my Mac Pro and other computers mainly atm).
 
What good does me saying I have an EE degree do? As if you'd believe me.

I would certainly respect your opinion a bit more.

Don't fool yourself- you've already made up your mind on this one.


Only in that Manufacturer's recommendations > Random Internet Guy with nothing to back up his assertions of "science fail."
 
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