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Re: battery life

> On   7 Apr, this message from Michael Schmitz echoed through cyberspace:
> >> >http://ryoko.camperquake.de/solutions
> >>
> >> Anyone tested it. Is that working?
> Tried it yesterday after my battery went down to 1514 max_charge.
> After studying some Li-ion battery docs, I found that end-of-discharge
> voltage for those batteries should be 3.0V. I noticed PMU still gave me
> 14.0V when charge was aproaching 0%; so I decided to let it drain down
> to 12.0V (4 cells in series). That gave me another 45 minutes of
> runtime.

Yep, that's what I noticed as well (in MacOS, not Linux). What's the
voltage calibration? My battery starts at a reading of 11911 ...

> The smart battery will stop delivering power at 12.0V, so the PowerBook
> will be shut off the hard way once at that point :-). So it's been shown
> the protection circuit of the battery works :-)).
> However, after recharging the battery, I haven't gained much capacity
> back: I now have a max_charge of 1574.

I've done the discharge in MacOS a few times (four or five times) and it
did help noticably (though not back to full capacity).

> So I guess it will just be time for a new battery soon....

I gave in and ordered a replacement battery from a third party
distributor. They must have bumped battery capacity in the Pismo models,
max charge of the new one is 5400, that lasts about 3.5 hours. Weird
things happen with both batteries installed: with AC connected, at least
the big one is continously discharging a bit then recharging.

> > I'll have to try that again now that battery life is degrading. Max
> > charge of 1745 is OK for Lombard, right?
> Looks good to me... My TiBook is down to 1574 :-(

Repeat the 'deep' discharge a few more times and check again. Might be
necessary to do a PMU reset even (I'm sure I had a PMU reset in the

> What do other people get as voltage reading when their battery is fully
> charged, and when aproaching 0% charge? I'd be interested to see if PMU
> always stops discharging 'early', as it obviously did for me (at 14.0V
> vs. end-of-discharge at 12.0V).

The old one starts at 11900, ends around 10530. Charge goes down to 6 and
time remaining to 15 sec. and this does slowly decrease for about five
minutes before the machine shuts down the hard way. Final voltage reading:
10379, with charge at zero for 15 minutes before powerdown.
Will test both batteries more thoroughly later today.


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