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KJdanReuben

macrumors regular
Original poster
May 22, 2007
153
0
I am currently running my macbook in closed mode. Will always having to be connected to a power source make the battery lose its charge faster when not plugged in? I think i've read somewhere that you aren't supposed to put lithium ion batteries on charge untill they get because of some sort of battery memory issue. Thanks in advance for answers!
 
It'll be fine. New Li-polymer batteries don't suffer nearly as much from memory effects as older batteries. Just be sure to calibrate your battery every month or two by running it all the way the down...gotta exercise those electrons every once in a while, but not all that often.
 
Also, Mac OSX is pretty smart. It knows when your battery is fully charged and stops charging it. The laptop runs off power from the power source, not the battery once it's been fully charged.
 
Also, Mac OSX is pretty smart. It knows when your battery is fully charged and stops charging it. The laptop runs off power from the power source, not the battery once it's been fully charged.


Oh, that's really cool. I never knew that. Thanks!
 
The "battery memory" issue never applied to Li-Ion cells - only NiCds. There is absolutely no benefit to cycling or fully discharging Li-Ion batteries with the exception of occasionally doing this to calibrate the "electronic fuel gauge".

As posted elsewhere, the battery management hardware/firmware takes care of the Li-Ion batteries. To extend life, the algorithm won't continue to charge the batteries after they are fully charged. Instead, it lets the batteries back down to maybe 96% SOC (State Of Charge) before charging again.

The charge algorithm is basically CC-CV - Constant Current-Constant Voltage. The batteries charge at a constant current until they reach a certain voltage (around 4.1V/Cell). Then the current tapers down to maintain this voltage (constant voltage) until they are fully charged. An "Electronic Fuel Gauge" gathers data from the performance of the battery in an attempt to accurately estimate the SOC and thus the remaining charge/runtime.

These algorithms are not unique to Apple computers. Li-Ion cells ALWAYS need to be treated this way.

Rob
 
Something I've always been curious about: Since Apple tend to make notebooks that vent through the keyboard, wouldn't closed lid mode tend to overhead the computer?
 
Something I've always been curious about: Since Apple tend to make notebooks that vent through the keyboard, wouldn't closed lid mode tend to overhead the computer?

I have my PowerBook running in desktop mode, aka closed lid, and I can feel the heat coming out the back. I've always thought the heat came through the keyboard, too... maybe it does both?
 
The keyboard is a mean of ventilation.

However, I wonder if using the clamshell mode (i.e lid closed) all the time would also damage the screen, esp. the soft surface ?
 
What size eternal monitors are you using with your macbook? Is it choppy or distorted at all in closed lid mode? Is there any slow-down with it while using BT might mouse and keyboard? (all while lid closed)

Thanks!
 
Something I've always been curious about: Since Apple tend to make notebooks that vent through the keyboard, wouldn't closed lid mode tend to overhead the computer?

I believe this was more of an issue with the iBook but because of the change in design, doesn't apply to the Macbook and Macbook pros anymore.
 
What size eternal monitors are you using with your macbook? Is it choppy or distorted at all in closed lid mode? Is there any slow-down with it while using BT might mouse and keyboard? (all while lid closed)

Thanks!

Those questions have nothing to do with the clamshell mode, running your computer in clamshell mode will not make a difference in performance; your fans may turn on more often, but thats mostly because the GPU has to work harder to render a larger image on your external monitor and will happen even if you run with the scren open in mirrored/extended mode.

There will always be intermittent lag with bluetooth devices, you're never gonna get away from it. Sound will be unaffected.
 
I've measured temperature rise with the lid open and closed and it doesn't make a lot of difference. It makes a bit more difference when the CPU is heavily loaded.

Rob
 
I too was worried about the screen and stuff getting too hot, here's what i figured out. If you start the computer in closed lid mode, you can open it after and it still acts as if it was closed. I thought this may help with ventalation, but i'm not sure.
 
I have my PowerBook running in desktop mode, aka closed lid, and I can feel the heat coming out the back. I've always thought the heat came through the keyboard, too... maybe it does both?

When ever you close the lid, you expose a vent that is normally somewhat covered by the open screen.

I too was worried about the screen and stuff getting too hot, here's what i figured out. If you start the computer in closed lid mode, you can open it after and it still acts as if it was closed. I thought this may help with ventalation, but i'm not sure.

Well one thing you could do is take something about the thickness of a pencil, and just place it between the lid and the computer around where the magnetic latch is. This will allow a bit more ventalation through the keys still, and the magnetic latch will still pull down on it, making it still think it's closed completely.
 
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