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Restore some life to your laptop's battery System
I've found a way to restore partially the duration of the battery of my iBook. It used to last 1hr 30m. Now it lasts more than two hours. Here's how I did it. Work normally using the battery. Wait for the warning about the battery. Open a terminal, you must be an admin user. Type:
 % sudo shutdown now
The password required is that of your account. At the end of shutdown you are in single user mode. Now you can wait until the battery will completely be discharged. You can accelerate the process typing fsck repeatedly.

When the computer turns off, put it in charge mode again. It may be that using this technique more than one time can increase the battery duration more and more. Sorry for my bad English!

[robg adds: I'm sure my [insert any non-English language] is worse than Marco's English! A friend points out that you can replace the fsck with yes > /dev/null, which simply eats processor time, as described in this hint.
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Restore some life to your laptop's battery | 12 comments | Create New Account
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Not A Good Idea At All
Authored by: neoguri on Feb 17, '03 10:22:30AM
This tip is AFAIK very much wrong.
Generally modern notebook use Li-Ion Bateries. They do *not* show age related wear that the old Ni-Cd batteries have. And they do *not* lose capacity when not fully depleated before being recharged. They actually lose capacity when left uncharged for some time.

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Not A Good Idea At All
Authored by: zerologic on Feb 17, '03 10:42:14AM

Which is of course why my battery lasts about 1/2 hr if I'm lucky. I using a PowerBook G4/500.


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Not A Good Idea At All
Authored by: j0nathan on Feb 17, '03 10:52:54AM

I had the same problem with the same machine. The problem I believe stems to around the time I upgraded to Jaguar - there are many on the Apple support forums with the same experience. Apple has been notably quiet. Over the past 4 months, I have read and implemented dozens of techniques for improving battery life that have done nothing. Eventually I bit the bullet and bought a new battery - I now get an astonishing 4 hours battery life which is more than I had when the machine was new or with any previous OS or PowerBook.

Could Jaguar possibly be the cause of the eroded batteries?

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Not A Good Idea At All
Authored by: bipto on Feb 17, '03 04:13:08PM

Hmm. My new 12" PB got 2.5+ hours out of the box but after 10.2.4 I notice it now gets barely 2 hours on a full charge. The thing is a month old, tops! I wonder if the update had anything to do with it...

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Restore some life to your laptop's battery
Authored by: NetCurl on Feb 17, '03 11:29:45AM

I have a possible (and this is an outside shot) cause/reason for the battery degradation. I recently bought a 1Ghz TiBook. I noticed that in the manual, it mentioned that sometime in the first week of owning your laptop, you should "condition" the battery by running it all the way down, and then charging it back up. I do know that Lithium-ion batteries are *supposed* to be immune to the problems that previous Ni-Cd battgeries had, but I also know that they require conditioning like this in order to ensure proper use in the future.

I've never had any problems with my two TiBook batteries, and I'm not saying it's because I did this, but I believe that it might be a helpful aid in maintaining a healthy battery.

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Authored by: rbl on Feb 17, '03 11:57:19AM

Maybe it's also my bad english but the process Marco described is simply a drain and recharge your battery process.

I don't know about your "recharging habits" but here's a couple of hints on how to save your battery (life):
- If you are not going mobile, unplug the battery when it's full.
If you are at your desk and don't plan to leave soon, unplug the battery when it's charged and work with the juice comming from the wall.
- If you can, don't stop or start recharging before it's finished.
- Energy Saver is very complete with many options for many user scenarios, use it and use it wisely.
- Use the drain and recharge process described by Marco at least once every week or month according to the amount of time you use the computer

That's it! =)



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Authored by: Azark on Feb 22, '03 01:35:51PM

Not a good idea.
Using the Titanium 1Ghz (don't know for other PB) without battery reduce processor speed and/or disable L3 cache. I don't remember exactly. There's a TIL on that.

PB Ghz 1024 Combo
G4 400 AGP

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Restore some life to your laptop's battery
Authored by: joon on Feb 17, '03 12:11:59PM

Seems like it would recalibrate the PMU or the internal circuitry in the battery. If a Li-ion battery looses capacity, then that's it. It's lost forever. It's not like Ni-Cd or Ni-Mh. They can be reconditioned, Lithium-ion which is used in all lap tops on the other hand cannot. I have 2 batteries for my Titanium. One of them lasts over 2 hours. The other lasts just over 30 minutes. Must be going bad..

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Restore some life to your laptop's battery
Authored by: timbloom on Feb 17, '03 04:47:01PM

This actually does work, not to the point it did with the old powerbook batteries though. I believe it has more to do with the PMU than the actual battery. What I personally suggest:
1.Drain the battery all the way down, using the above hint.
2.Reset your PMU (each mac is different, see apple knowledge base for your specific instructions)
note-follow directions EXACTLY to the word!
3.Leave computer off and attach completely discharged battery.
4.Plug it in and let it fully charge before using it.
5.Drain battery again
6.Recharge fully

This tells the PMU to forget everything, and readjust to this "conditioned" battery.
Logically, this should work. Just resetting the PMU might fix many peoples problems, but if the battery is toast, it's toast.

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Restore some life to your laptop's battery
Authored by: Marco Cottone on Feb 18, '03 12:31:26PM

I did it all and that extended the life of another half an hour.
I do not expect more from a battery daily recharged for over a year.

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Restore some life to your laptop's battery
Authored by: jashmenn on Feb 22, '03 12:48:22PM

My battery is drained and recharged nearly everyday and resetting the
PMU brought my battery life from about 1 hour to almost to 2 (1:57 after

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It shouldn't work
Authored by: xtigger on Feb 17, '03 05:30:10PM

I suspect what you really need to do is reset the PMU. See Applecare Knowledge Base doc 14449.

It's a pain; resets lots of stuff. But it fixed my problems. I went from less than 2 hrs to around 4 hrs battery life.

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