PowerBook 500 Series Battery Rebuild Failure (Oops, all dead EMMs!)
- Thread starter 3lectr1cPPC
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3lectr1cPPC
Well-known member
The other one has no power on pin 13 but has power on several other pins which is weird…
3lectr1cPPC
Well-known member
The battery that works is also cutting out randomly, which I’d suspect to be an issue with the ribbon connection? Didn’t you have something similar? This is the one with corrosion, so I may have to bypass the ribbon connection to battery positive.
jmacz
Well-known member
What do you mean by cutting out? The battery detects/doesn't detect in the laptop or charging starts/stops?
I had an issue where the battery kept detecting/not detecting in the laptop and that turned out to be the memory chip which I replaced. In my limited experience with these batteries, if either EMMpathy or Lind are able to correct all errors in the battery and on a subsequent check it detects no errors, the memory is probably good. You only have a potential memory issue if neither tool is able to correct it no matter how many times you try.
I also had an issue where the battery kept trying to charge but kept stopping every 30 seconds or so. That turned out to be the charger (where I had a faulty 16V 2A supply). Replacing the charging half fixed that issue.
The battery I couldn't get working at all was the one with the "short" in it .. power was getting to the chip but it wasn't behaving right. I think that chip is dead but I will pull that one out and some point and see if I can debug it further. But it's way down on my back burner since I have two working ones.
3lectr1cPPC
Well-known member
EMMpathy smart probe is showing a rapid voltage drop from the cells down to about 8V until it dies. Also says it’s at 100% so it won’t try to charge.
3lectr1cPPC
Well-known member
That’s not good. Says shorted cell when I plug it in.
I did briefly short of the pack for less than a second when I was assembling this pack, I wonder if I fried it. I may try swapping in the other cell pack.
3lectr1cPPC
Well-known member
Swapped the other cells in and they’re low on charge, aaaaand, they won’t charge with my supply with just the VBATT line. So now I need to figure that out. Will probably get that second supply and wire it up.
3lectr1cPPC
Well-known member
Absolutely! I think this one battery should work out once I've gotten a proper charging solution made. Thanks a lot for your help all throughout this process.
I’m sorry I haven’t been any help - thank you for tagging me, jmacz - I’ve started the year away on holiday for a month.
I have four EMM boards that don’t respond (EMMPathy waits for the EMM to come online and it doesn’t) - so I have a way to go yet, but I do have one working battery which charges off the original power supply. I do think VBATT must be limited to about an amp, for the battery to be charged properly
I have four EMM boards that don’t respond (EMMPathy waits for the EMM to come online and it doesn’t) - so I have a way to go yet, but I do have one working battery which charges off the original power supply. I do think VBATT must be limited to about an amp, for the battery to be charged properly
Not that it helps, but I received two batteries from the USA at long last, from a friend visiting me in NZ. These batteries came with two 520c machines that I bought off eBay but - in a long and convoluted story - couldn’t be sent to me because of the batteries, so I had them sent to my friend in Maryland instead. That was well over a year ago.
I wasn’t expecting much, but both batteries showed no signs of corrosion (externally looked like new) and - unlike my collection of dead batteries - both had Sanyo cells. To my utter amazement; one battery (with 342 cycles) charged up and ran the machine for about 15 minutes - and the other wouldn’t charge (shorted cell) but the EMM was at least responding!
I opened the pack with the shorted cell to find one cell reversed (negative voltage) but no real corrosion to speak of: very different to the crystallised, crusty white mess of the Panasonic packs.
It was straightforward to fit some tabbed cells that I had bought from AliExpress; but these really do not seem to work correctly. Despite claiming a 2600mAh capacity, the measured capacity after calibration (not shown here) is more like 500mAh and the runtime only about 10 minutes. My 540c with new LCD and CF card in the Apple-supplied IDE to SCSI adapter is a thirsty beast; note the current draw of over an amp (and the charge rate is also over an amp).
The cheap cells get quite hot in charging (as seen here), capacity seems to be getting worse (I tried a Lind Battery Utilities reset, so it thought it was good again but it definitely wasn’t), and therefore, I don’t think the cells can handle the charge or discharge rate of around 1A (and are actually getting damaged). I will replace them with more ‘local retail’ cells (Jaycar store brand), 2300mAh claimed and about 1500mAh actual. Anyway, I am lucky enough to have two more working EMMs, I think my problem now just lies in finding appropriate cells. Maybe Energizers from the supermarket with strips spotwelded on!
And, my suggestion is that the Sanyo packs may survive better than Panasonic (BS in serial not BP) although my exhaustive study on this matter has a sample size of seven (two Sanyo, both working EMMs, and five Panasonic, one working EMM)
I do need to find a solution for the 2x VL-2330 PRAM battery. It has taken months but the two orders I placed never reached me - dangerous goods - so I wonder whether 2x CR2032 and a series diode to prevent charging might work? Bit desperate for a fix now, as without a PRAM battery the machine won’t start off the main battery unless it is powered up off AC to recognise the battery first. This is surprisingly inconvenient and also, because the dead PRAM battery is still in there, the main battery seems to go flat in a day or two trying to charge it. If anyone has tried running a Powerbook 500-series with a non-rechargeable PRAM battery and a diode, I’m interested to hear if it works (or whether it runs flat in a few weeks or doesn’t have enough voltage through the diode, etc.)
Cheers
I wasn’t expecting much, but both batteries showed no signs of corrosion (externally looked like new) and - unlike my collection of dead batteries - both had Sanyo cells. To my utter amazement; one battery (with 342 cycles) charged up and ran the machine for about 15 minutes - and the other wouldn’t charge (shorted cell) but the EMM was at least responding!
I opened the pack with the shorted cell to find one cell reversed (negative voltage) but no real corrosion to speak of: very different to the crystallised, crusty white mess of the Panasonic packs.
It was straightforward to fit some tabbed cells that I had bought from AliExpress; but these really do not seem to work correctly. Despite claiming a 2600mAh capacity, the measured capacity after calibration (not shown here) is more like 500mAh and the runtime only about 10 minutes. My 540c with new LCD and CF card in the Apple-supplied IDE to SCSI adapter is a thirsty beast; note the current draw of over an amp (and the charge rate is also over an amp).
The cheap cells get quite hot in charging (as seen here), capacity seems to be getting worse (I tried a Lind Battery Utilities reset, so it thought it was good again but it definitely wasn’t), and therefore, I don’t think the cells can handle the charge or discharge rate of around 1A (and are actually getting damaged). I will replace them with more ‘local retail’ cells (Jaycar store brand), 2300mAh claimed and about 1500mAh actual. Anyway, I am lucky enough to have two more working EMMs, I think my problem now just lies in finding appropriate cells. Maybe Energizers from the supermarket with strips spotwelded on!
And, my suggestion is that the Sanyo packs may survive better than Panasonic (BS in serial not BP) although my exhaustive study on this matter has a sample size of seven (two Sanyo, both working EMMs, and five Panasonic, one working EMM)
I do need to find a solution for the 2x VL-2330 PRAM battery. It has taken months but the two orders I placed never reached me - dangerous goods - so I wonder whether 2x CR2032 and a series diode to prevent charging might work? Bit desperate for a fix now, as without a PRAM battery the machine won’t start off the main battery unless it is powered up off AC to recognise the battery first. This is surprisingly inconvenient and also, because the dead PRAM battery is still in there, the main battery seems to go flat in a day or two trying to charge it. If anyone has tried running a Powerbook 500-series with a non-rechargeable PRAM battery and a diode, I’m interested to hear if it works (or whether it runs flat in a few weeks or doesn’t have enough voltage through the diode, etc.)
Cheers
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jmacz
Well-known member
And, my suggestion is that the Sanyo packs may survive better than Panasonic (BS in serial not BP) although my exhaustive study on this matter has a sample size of seven (two Sanyo, both working EMMs, and five Panasonic, one working EMM)
You might be right... both of my working batteries had Sanyo cells in them.
3lectr1cPPC
Well-known member
Pretty sure mine were Panasonic.
croissantking
Well-known member
Just to chime in on the findings in this thread, I’ve just rebuilt one of my batteries, and it hasn’t worked. Lind and Emmpathy cannot find the battery in the right-hand slot.
The donor battery looked great internally with very little signs of corrosion so I’m a bit surprised. I have three more of these batteries so would it be worth switching the battery pack into another unit to test?
The donor battery looked great internally with very little signs of corrosion so I’m a bit surprised. I have three more of these batteries so would it be worth switching the battery pack into another unit to test?
jmacz
Well-known member
The two cases I have seen where the battery didn't detect was 1.) the ribbon inside that connects the outer terminals to the EMM board had some deterioration due to the corrosion (fixed by replacing the ribbon with wires). 2.) the Apple proprietary EMM chip itself was bad.
I've also had to replace the memory chip on the EMM board but that didn't cause battery detection issues. That was just preventing Lind from "correcting" it with proper values.
I've also had to replace the memory chip on the EMM board but that didn't cause battery detection issues. That was just preventing Lind from "correcting" it with proper values.
croissantking
Well-known member
Does the EMM board need to be hooked up to a working battery pack in order to be detected?
jmacz
Well-known member
Hmm, I don't remember if I tried that or not. It's a good question. Can you hook up the EMM board to the actual laptop without a battery pack and see if the laptop will power the EMM? Yeah, I don't know. I'm curious too now. But I'd have to disassemble my 540c and one of my rebuilt packs to test that. I'm actually kinda curious though... let me see if I can find some time to try that this weekend.
jmacz
Well-known member
@croissantking I opened up one of my working batteries, disconnected the battery from it, then closed it back up and tried it in my 540c. The laptop is NOT detecting the battery (with or without the power brick connected -- for the without test, I had a second battery in the other slot powering the laptop). It looks like the EMM is only powered via the battery pack.
EDIT: and after the battery pack was reconnected, the laptop is detecting the battery again.
EDIT: and after the battery pack was reconnected, the laptop is detecting the battery again.
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croissantking
Well-known member
Thanks for your investigations @jmacz - I’m feeling more confident now that I’ll get one of the other EMM boards to work.
croissantking
Well-known member
Well, I have tried connecting up another EMM board to my battery pack, but the results are the same - the battery is not detected by Lind or Emmpathy.
I feel like I’ve missed something obvious here.
I feel like I’ve missed something obvious here.
