croissantking
Well-known member
Have installed a rebuilt PRAM battery as well, this is great, I can power on without the charger!
PowerBook 500 Series Battery Rebuild Failure (Oops, all dead EMMs!)
- Thread starter 3lectr1cPPC
- Start date
jmacz
Well-known member
Awesome, glad that worked!
croissantking
Well-known member
With one battery I get around 1:15 runtime, what about you?
jmacz
Well-known member
Mine was around 2:30-3:00 with two batteries so that sounds about right? Mine is overclocked but this was just messing with applications, etc, not running something that was intensive.
Hi, thanks for your discussion that provided many important tips on rebuilding a PB500 battery. I also tried to rebuild one by myself but there are some issues confusing me.
A. I replaced 93c66 chip from other EMM board and corrected data LIND BU500 so my PowerBook 520c can recognize the battery now, and I can even boot up without AC adapter. However it can't be charged. I tried to drain out power of the battery but nothing changed. Both LIND and Apple Intelligent Battery Recondition software report my battery has error can't be corrected. Should I try to replace EMM chip or something else?
B. Why I didn't mention EMMpathy above? Oh because I tried to open EMMpathy 2.1, but it always says "Couldn't load the preferences“ and close. Do you have any idea to solve it?
A. I replaced 93c66 chip from other EMM board and corrected data LIND BU500 so my PowerBook 520c can recognize the battery now, and I can even boot up without AC adapter. However it can't be charged. I tried to drain out power of the battery but nothing changed. Both LIND and Apple Intelligent Battery Recondition software report my battery has error can't be corrected. Should I try to replace EMM chip or something else?
B. Why I didn't mention EMMpathy above? Oh because I tried to open EMMpathy 2.1, but it always says "Couldn't load the preferences“ and close. Do you have any idea to solve it?
jmacz
Well-known member
Did you confirm that your power adapter is putting out both 16V outputs? One pin is for running the laptop and a second one is for charging the battery. You should check both pins are putting out the right voltage.
Where did you get the 93c66 chip from? Was it from another old battery or was it a new part?
I have no idea on the EMMpathy issue but you could check if the preferences file is in the Preferences folder in the System Folder and see if it’s damaged or just delete it and try again?
Where did you get the 93c66 chip from? Was it from another old battery or was it a new part?
I have no idea on the EMMpathy issue but you could check if the preferences file is in the Preferences folder in the System Folder and see if it’s damaged or just delete it and try again?
Wow, thank you jmacz! Yes I deleted EMMpathy preferences file in the Preferences folder and it works. And after diagnostic the battery can be charged now. It's time to rebuild PRAM battery haha.
jmacz
Well-known member
Hmm...
The two red eeprom values on the right side shouldn't be like that. EDIT: actually, I remember now, this might happen if you end up switching between the various battery tools. I remember every time I switch between EMMpathy, Lind, and Apple's, this would happen because each tool writes out and has its own idea of what the right values should be.
For the temperature, yeah, there should be a reading there and the fact that it's not reading might be why the battery is not charging? There's a temperature sensor inside the battery (should have been taped to the plastic case underneath the battery. Might want to check that and ensure the leads coming from it still have a solid connection to the EMM board, and that the sensor isn't cracked?
For the temperature, yeah, there should be a reading there and the fact that it's not reading might be why the battery is not charging? There's a temperature sensor inside the battery (should have been taped to the plastic case underneath the battery. Might want to check that and ensure the leads coming from it still have a solid connection to the EMM board, and that the sensor isn't cracked?
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3lectr1cPPC
Well-known member
Double check both voltage rails on your charger are working.
jmacz
Well-known member
I got two more batteries, both are Apple made.
@alexGS more data for you: one of the batteries was a Sanyo (BS) and the other was a Panasonic (BP). The Sanyo was in great condition, no leaking inside. The Panasonic was leaking badly and the battery terminal contacts were heavily corroded. I think you also noticed your Sanyos were better than your Panasonics.
Luckily both EMM boards were intact and don't seem to have any corrosion on them.
I had not noticed this before, but looks like the EMM chip is marked differently between the two battery vendors. The Sanyo is an EMM-S and the Panasonic is an EMM-P. Not sure if there are major differences or whether they are marked differently as they are preloaded with different battery data (which must be the case as some of the battery tools clearly ask you whether the battery is a Sanyo or Panasonic).
With regards to rebuilding the batteries, curious if one set of settings is better than the other in terms of the aftermarket NiMH cells we're using to replace the dead Sanyo/Panasonic ones.
Hopefully the EMM board from the Panasonic is ok so that I can compare it against the two working BS/Sanyo packs I have.
@alexGS more data for you: one of the batteries was a Sanyo (BS) and the other was a Panasonic (BP). The Sanyo was in great condition, no leaking inside. The Panasonic was leaking badly and the battery terminal contacts were heavily corroded. I think you also noticed your Sanyos were better than your Panasonics.
Luckily both EMM boards were intact and don't seem to have any corrosion on them.
I had not noticed this before, but looks like the EMM chip is marked differently between the two battery vendors. The Sanyo is an EMM-S and the Panasonic is an EMM-P. Not sure if there are major differences or whether they are marked differently as they are preloaded with different battery data (which must be the case as some of the battery tools clearly ask you whether the battery is a Sanyo or Panasonic).
With regards to rebuilding the batteries, curious if one set of settings is better than the other in terms of the aftermarket NiMH cells we're using to replace the dead Sanyo/Panasonic ones.
Hopefully the EMM board from the Panasonic is ok so that I can compare it against the two working BS/Sanyo packs I have.
3lectr1cPPC
Well-known member
This reminds me - I picked up another EMM board and battery shell (no cells) from EvieSigma at the VCF Swap Meet in June. I've got to set some time aside to see if I can get that one running again. It's marked EMM-P.
Hello - yes, that was the case
To summarise my experience in the months since, the problem I ran into was finding cells that can cope with the charge rate without deteriorating. I was using tabbed AA cells in blue wrap, labelled ‘XH NiMH 2600mAh’, bought from AliExpress. After just a few charge cycles (full discharge to shutoff using Battery Amnesia, and then charge), the capacity was reported as just 488mAh (not the 1752mAh expected). Resetting using the Lind Battery Utilities and charging again made it even worse.
I bought tabbed AA rechargeable cells from a local supplier (their own brand) and I got on better with those; claimed capacity 2000mAh and actual reported about 1500mAh. I went back to the same supplier for their 2400mAh cells also of their own brand. These turned out to be regular button-ended cells with tabs welded on. Interestingly, by carving a hole (in the side opposite the battery pack connector), I was able to accomodate the increased length of these cells. That means any high-current AA rechargeables could be used, lowering the cost of the recell project (I have a spot-welder). I will try to find a photo.
As far as performance goes, the 2400mAh cells work about the same - 1500mAh - but at least they seem to cope with the 1014mA charge rate that my Powerbook 540c delivers.
So, that’s my recommendation - have to find top-performing cells that can handle the charge current - otherwise, it’s not worth the time taken to fit the cells.
One other very important nugget of information; I was restoring a 520c and managed to replace the PRAM battery (two VL-2330 cells as I’m sure everyone reading this knows by now). It was expensive and difficult getting those cells into New Zealand but I got there in the end (AliExpress, had to come from Singapore). When I took the same main battery from my 540c and put it in the 520c, not only would it now start up without needing to be plugged in first (an expected outcome), but also, the standby time for the battery had greatly increased from about a day to a week or more, making it actually useful. I guess my 540c must be wasting energy in trying to charge the dead PRAM battery. I suppose removing the PRAM battery might be a partial solution, but I have ordered two more VL-2330s anyway.
Does EMMPathy report the 2A charge rate? That seems too high to me, but it’s good that you’ve found cells that can handle it. What is your measured capacity in EMMPathy after a full discharge/recharge? I would find it inspiring if you’re getting over the 1752mAh default capacity, I can’t seem to quite reach it
Annoyingly I can’t find a photo of the casing modifications necessary to accomodate the button-end AA cells; basically the inner ribs are shaved from the ends where three cell pairs fit, and then the fourth pair of cells (in line with the pack’s gold terminals) need to have a 14mm hole cut through the end (carved from the two halves) so the flat cell end (with tab attached) can stick out just a little. This is concealed anyway when the cover goes on. A picture would be worth a thousand words!
The merit of all this is that regular button-positive AA cells are much cheaper/easier to find than tabbed (flat-positive) AA cells. I hope to find some genuinely high-performance cells soon.
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jmacz
Well-known member
EMMpathy Smart Probe shows:
Battery 1
Battery 1
- Factory Default: 1752mAH
- Measured Total: 1752mAH (I also have been unable to go higher than this)
- Measured Battery Current (while charging): 1924 mAmps
- True Capacity (noted in the text box): 1752mAH
- Factory Default: 1752mAH
- Measured Total: 1752mAH (again, haven't seen higher, but also haven't seen lower either)
- Measured Battery Current (while charging): 1898 mAmps
- True Capacity (noted in the text box): 1752mAH
jmacz
Well-known member
I remember in the other thread you had mentioned that the battery will pull as much as the vbatt power supply will put out. So I do have the 2A power supply for vbatt so looks like it's drawing near that 2A mark. Both batteries have been doing fine although one does a little bit better than the other and that makes sense since one of the packs I used was a 2100 mAH and the other was a 2000 mAH.
jmacz
Well-known member
Ok, I have another battery pack working (it was the Sanyo one). There were some errors but EMMpathy was able to fix them, I didn't have to change the memory chip on this one.
I've got the Panasonic one waiting for a new battery pack. Will build that one later.
Yay, 3 for 4 on rebuilds. Hopefully I can make it 4 for 5, but not sure why I need four batteries
I've got the Panasonic one waiting for a new battery pack. Will build that one later.
Yay, 3 for 4 on rebuilds. Hopefully I can make it 4 for 5, but not sure why I need four batteries
jmacz
Well-known member
I had mentioned this before but just noting I saw this again. Looks like Lind and EMMpathy are at odds with each other on what they feel like the correct battery values should be. What I have noticed is if I used Lind to correct things and then open EMMpathy, EMMpathy sees errors. Once corrected there, if I go back to Lind, Lind sees errors. Staying with the same tool results in no errors on subsequent validations. I don't think either of the tools is doing the wrong thing, it's just they are probably writing slightly differing values and thus they report errors when the other tool is used.
Now that said, when rebuilding these batteries, I use Lind first. What I have noticed is that if you use EMMpathy first, it seems to have a hard time determining the measured capacity. Every time I have built a pack and used EMMpathy first to correct the errors, the measured capacity seems to be 0 which then causes the system to suspend (after pulling the cord) even though the pack is fully charged. If I use Lind, it seems to reset the measured capacity (to 1752 mAH) and after that, the battery works regardless of which tool you use.
Now that said, when rebuilding these batteries, I use Lind first. What I have noticed is that if you use EMMpathy first, it seems to have a hard time determining the measured capacity. Every time I have built a pack and used EMMpathy first to correct the errors, the measured capacity seems to be 0 which then causes the system to suspend (after pulling the cord) even though the pack is fully charged. If I use Lind, it seems to reset the measured capacity (to 1752 mAH) and after that, the battery works regardless of which tool you use.
