Hot-swappable Battery?

Question

Hot-swappable Battery?

I had a 15" PowerBook G4, and one of my favorite features was the hot-swappable battery -- if you needed to switch to a spare battery, you could just close the lid, quickly take out the old battery and put in a fresh one.

I've tried this on my MacBook Pro, and every time I do it shuts down on me.

My question is, does this mean that battery hot-swap isn't supported? Or is there some small internal battery in my MacBook Pro (that would allow this) not functioning properly?

MacBook Pro 15" 2.16 Core Duo, Mac OS X (10.4.8)

Posted on Jan 11, 2007 4:45 PM

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Answer 1

Jan 11, 2007 4:46 PM in response to David Chesney

I only vaguely remember something about an internal battery on PowerBook G4 models -- I have no idea if that's actually the case.

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Answer 2

Jan 11, 2007 5:03 PM in response to David Chesney

The MBPs can in fact hot-swap batteries. While it doesn't exactly work the same as the PowerBooks it does work fine and in some ways it's better than the PBs. If you have disabled Safe Sleep then this is your problem as you need it. With a Safe Sleep, everything in RAM gets copied to hard drive so when it loses power, all can be restored. So, all you need to do is to sleep your MBP, and when your remove the battery, yes it just shuts off, however, when you return a battery and push the power button it will restore properly from Safe Sleep.

The PBs did it differently and used the PRAM battery to maintain sleep, for around a minute or so, while you swapped batteries. The MBPs can be in Safe Sleep indefinitely.

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Answer 3

Jan 11, 2007 5:20 PM in response to infinite vortex

I just tried to hot swap, following these instructions:

http://docs.info.apple.com/article.html?artnum=303329

It shut down completely.

I have not disabled safe sleep, that I know of.

Edit: Ok. I just tried again and it worked. I don't think I've been waiting long enough. This time I waited for the sleep indicator light to pulse and it worked.

Thanks for the help, it's greatly appreciated.

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Answer 4

Willett58

Level 2

220 points

Jan 11, 2007 5:22 PM in response to David Chesney

I do not find any option for safe sleep. New C2D 15.4" laptop.

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Answer 5

Jan 11, 2007 5:30 PM in response to Willett58

It's automatic, I believe.

"Entirely unbeknownst to me while writing the review, new PowerBooks now support a new “Safe Sleep” mode, where the contents of RAM are written to disk before sleep, so that if the battery is completely depleted during regular sleep, the computer will still “wake up” and restore your session when you plug in a power adapter or fresh battery. It’s not something you have to turn on, or a new way to put your computer to sleep. It’s something that kicks in automatically if you run out of juice while in normal sleep mode."

-- http://daringfireball.net/2005/11/fmj_addenda

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Answer 6

Jan 11, 2007 5:31 PM in response to Willett58

How are you getting by with 2MB of RAM?

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Answer 7

ravuya

Level 2

425 points

Jan 11, 2007 9:22 PM in response to Willett58

There's a special key combination to force your Mac into a deep sleep; I think it involves some combination of keys and the power button.

It's on Apple's site, in any event.

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Answer 8

Jan 12, 2007 12:58 AM in response to Willett58

I do not find any option for safe sleep.

That's because it's something Apple doesn't want you to turn off. You need to use Terminal (UNIX command line), a script or 3rd party utility to turn off.

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Answer 9

Red Dwarf

Level 6

14,920 points

Jan 12, 2007 1:14 AM in response to ravuya

There's a special key combination to force your Mac into a deep sleep; I think it involves some combination of keys and the power button.

Command(Apple) + alt + The Eject key (next to F12) is the key combination. However, simply closing the screen and waiting for the sleep light to start pulsing achieves the same thing.

RD

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