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Macintosh PowerBook 145/160/170 battery replacement


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#61 Rajel

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Posted 22 March 2017 - 05:36 PM

So, I had the machine booted up with the SCSI2SD last night, ran like a champ.
Didn't even come close to draining the battery before shutting down for the night.
Booted it up this morning, and it appears the battery has almost completely drained - anyone else see this behavior? I'd think there shouldn't be power drain while the system is shut off.


Macs: soon-to-be-tricked-out PB160 w/10MB RAM and custom battery. Upcoming upgrades: 66MHz crystal, SCSI2SD, wifi/ethernet access via DreamPi. Powerbook G4 5,4 w/1GB ram, dualboot OSX 10.5 and MorphOS. Mac Mini G4 1.25GHz running MorphOS. Core i5 Mac Mini slotloader that's eaten my damn Gunlord CD.
PCs: Too many, running too many things.


#62 zuctronic

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Posted 22 March 2017 - 05:41 PM

Maybe it's trying to charge a dead PRAM battery? I actually have a similar issue. I also wonder at what voltage level does it force sleep / shutdown. I have a rebuilt batpack with 10 cells in it and this new printed one with 5 cells and neither seem to last as long as I'd expect.



#63 Rajel

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Posted 22 March 2017 - 05:44 PM

My first thought was PRAM battery. I'm running 6 in the printed pack (the system regulates battery output anyway) and while running last night I never saw the meter level drop at all.
I do need to swap the PRAM battery anyway, guess that'll be the next fix.


Macs: soon-to-be-tricked-out PB160 w/10MB RAM and custom battery. Upcoming upgrades: 66MHz crystal, SCSI2SD, wifi/ethernet access via DreamPi. Powerbook G4 5,4 w/1GB ram, dualboot OSX 10.5 and MorphOS. Mac Mini G4 1.25GHz running MorphOS. Core i5 Mac Mini slotloader that's eaten my damn Gunlord CD.
PCs: Too many, running too many things.


#64 zuctronic

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Posted 22 March 2017 - 05:48 PM

Hmm... I know I can fit 6 cells in there, but it seems a bit ill-advised - I don't know enough about the voltage regulator. Are you sure that won't burn anything out? I'm completely ignorant in this area, I'm just afraid of destroying something that's difficult to repair.

I have the opposite problem though, the voltage drops down to "two bars" very quickly and then hangs there for about an hour before it dies hard.



#65 Rajel

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Posted 22 March 2017 - 05:59 PM

Well, the PSU itself is 7.5v/2A. The system doesn't run at that voltage/current, it's regulated down. Same for the "6v" from the stock battery. Battery voltage fluctuates enough that good regulation is required. Most can handle a decently wide range; not sure what the PB160's battery regulator maxes at, but I've had no ill effects other than the system overall getting slightly warm - not anywhere near as warm as my G4 gets, but you'd want to have this on your lap on a cold night.
I could install a switching DC-DC convertor to give it a steady 6V out, but the issue then is more wasted energy from the conversion as it's a two-step process now, when it could be done with just the one. My friendly engineer buddy assured me that 6 cells in the pack was rather safe.
Worst case, I'll pin down the regulator coming off the battery inputs, and work out a swap for something more efficient which would reduce heat *and* extend battery life slightly.
...heck that actually sounds like a good idea, might do that anyway.


Macs: soon-to-be-tricked-out PB160 w/10MB RAM and custom battery. Upcoming upgrades: 66MHz crystal, SCSI2SD, wifi/ethernet access via DreamPi. Powerbook G4 5,4 w/1GB ram, dualboot OSX 10.5 and MorphOS. Mac Mini G4 1.25GHz running MorphOS. Core i5 Mac Mini slotloader that's eaten my damn Gunlord CD.
PCs: Too many, running too many things.


#66 zuctronic

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Posted 22 March 2017 - 06:02 PM

Ah, your explanation makes perfect sense and makes me feel a lot more comfortable about using six cells. Did you also take the klixon from the original battery pack?



#67 Rajel

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Posted 22 March 2017 - 06:05 PM

Nope, I'm actually just running straight battery. I had a fuse on it but then realized that the fuse itself actually shorted the back (which probably just blew immediately)


Macs: soon-to-be-tricked-out PB160 w/10MB RAM and custom battery. Upcoming upgrades: 66MHz crystal, SCSI2SD, wifi/ethernet access via DreamPi. Powerbook G4 5,4 w/1GB ram, dualboot OSX 10.5 and MorphOS. Mac Mini G4 1.25GHz running MorphOS. Core i5 Mac Mini slotloader that's eaten my damn Gunlord CD.
PCs: Too many, running too many things.


#68 Rajel

Rajel
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Posted 22 March 2017 - 06:10 PM

The protection really isn't as needed unless you're charging the cells from the PB itself, and right now I just charge them individually in the Eneloop's included charger.


Macs: soon-to-be-tricked-out PB160 w/10MB RAM and custom battery. Upcoming upgrades: 66MHz crystal, SCSI2SD, wifi/ethernet access via DreamPi. Powerbook G4 5,4 w/1GB ram, dualboot OSX 10.5 and MorphOS. Mac Mini G4 1.25GHz running MorphOS. Core i5 Mac Mini slotloader that's eaten my damn Gunlord CD.
PCs: Too many, running too many things.


#69 zuctronic

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Posted 22 March 2017 - 06:29 PM

I see. But also if the only way these PBs know the charge level is via the voltage output, it might not charge 6 cells properly or fully anyway - right?



#70 Rajel

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Posted 22 March 2017 - 06:47 PM

Also probably true. Generally, I'm probably going to stick to external charging for the individual cells.


Macs: soon-to-be-tricked-out PB160 w/10MB RAM and custom battery. Upcoming upgrades: 66MHz crystal, SCSI2SD, wifi/ethernet access via DreamPi. Powerbook G4 5,4 w/1GB ram, dualboot OSX 10.5 and MorphOS. Mac Mini G4 1.25GHz running MorphOS. Core i5 Mac Mini slotloader that's eaten my damn Gunlord CD.
PCs: Too many, running too many things.


#71 Rajel

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Posted 22 March 2017 - 10:33 PM

I have the opposite problem though, the voltage drops down to "two bars" very quickly and then hangs there for about an hour before it dies hard.

And this is actually something of an issue with these rebuilt packs - NiMH cells hold voltage pretty well, the voltage drop is really slow for most of the runtime, and then it drops very sharply.
Basically, the metering is pretty much useless.


Macs: soon-to-be-tricked-out PB160 w/10MB RAM and custom battery. Upcoming upgrades: 66MHz crystal, SCSI2SD, wifi/ethernet access via DreamPi. Powerbook G4 5,4 w/1GB ram, dualboot OSX 10.5 and MorphOS. Mac Mini G4 1.25GHz running MorphOS. Core i5 Mac Mini slotloader that's eaten my damn Gunlord CD.
PCs: Too many, running too many things.


#72 Westinghouse

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Posted 23 March 2017 - 06:22 PM

Techknight, I came across a mention of putting a resistor between two pins in another of your posts on the subject.

 

https://68kmla.org/f...crazy/?p=297998

 

Wondering if you remember which two pins?






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