Well I almost burnt the house down. Time to ask for some help....

OnTheRoadAgain

Solar Addict
Did you notice the date of the last post....before yours ?
The member who started this thread was last seen a month after starting this thread. last year.
That might suggest he gave up on Lithium based batteries. Maybe solar or went back to Lead acid batteies. Who knows.

That said....I wonder how many of his batteries were salvageable (if any).
I just found this thread today because you revived it. I felt badly for the OP. $4000 wasted is an annoyance for some, devastating for others.
This is my own nightmare with these batteries.
It only takes a small mistake or equipment failure to lose a ton of money.

If your BMS fails it's job, ever, for ANY reason......magic smoke.
I wonder if you can install a redundant BMS' on one battery pack? (it's what would be required in a passenger airliner)
 

ken morgan

Solar Addict
The member referred to was trolling and his post was deleted, in case you didn't notice. Plus as others have said you are responding to a post that's a year old.
whats a old post between people who are searching? at least its not a full on zombie thread from 5 years ago...
 

Dave Knapp

New Member
Good day. I find myself in almost the same situation as this, except that I haven't hooked everything up yet. I bought 32 CALB 3.2 v, 150 Ah cells that were bundled in fours, bound with fiberglass straps and bakelite end plates. They were arranged with every other one reversed, and had bus bars attached for a 12.8 v 4s battery. Two of the original 32 were bad, one with 0 volts and one that was a little swollen. I cut open the 2 bundles and returned to 2 defective cells and am awaiting the replacements. I have 2 Daly 48v, 16s, 150a BMS's. I have arranged the first 16 cell bank, choosing the cells that had the least voltage difference. the lowest is 3.27v and the highest is 3.32v. Daly, and Will, (and others I'm sure) say to put the cells in parallel so they can equalize, although Daly says they should be within 0.05v, which these are. Rather than taking all of the cells out of their it would be simpler to link them in parallel with wire. I have no idea what current we're talking about in this equalizing. Would #10 wire do the job?
 

ken morgan

Solar Addict
Good day. I find myself in almost the same situation as this, except that I haven't hooked everything up yet. I bought 32 CALB 3.2 v, 150 Ah cells that were bundled in fours, bound with fiberglass straps and bakelite end plates. They were arranged with every other one reversed, and had bus bars attached for a 12.8 v 4s battery. Two of the original 32 were bad, one with 0 volts and one that was a little swollen. I cut open the 2 bundles and returned to 2 defective cells and am awaiting the replacements. I have 2 Daly 48v, 16s, 150a BMS's. I have arranged the first 16 cell bank, choosing the cells that had the least voltage difference. the lowest is 3.27v and the highest is 3.32v. Daly, and Will, (and others I'm sure) say to put the cells in parallel so they can equalize, although Daly says they should be within 0.05v, which these are. Rather than taking all of the cells out of their it would be simpler to link them in parallel with wire. I have no idea what current we're talking about in this equalizing. Would #10 wire do the job?
30 amps on #10 if copper. Insulation of the wire will make a difference though. I would say yes its adequate as you should be balancing in parallel at 3.65 volts and most power supplies that people here on the forum use are in the 5-10 amp range how large is your power source?
 

A.Justice

Swears he didn't start that fire.
That cell really expanded and didn't pop it's blow hole.

Video time... put it in the middle of the yard and keep charging it for the blow hole venting. I haven't seen any aluminium cells overcharge/ venting videos. ;)

This should satisfy your blowhole itch. 😂
 

Dave Knapp

New Member
30 amps on #10 if copper. Insulation of the wire will make a difference though. I would say yes its adequate as you should be balancing in parallel at 3.65 volts and most power supplies that people here on the forum use are in the 5-10 amp range how large is your power source?
Never done this before. I wasn't thinking of a power source at this stage, just wiring them up in parallel, in the bundles of 4, and letting them sit for a day - then putting them back in series and charging them in 12.8v bundles. To be honest, I wasn't prepared for this to be so complicated. But now that I have over $2K in the batteries, I need to make it work without putting an Electrical Engineer on the household staff.
 

Hedges

I See Electromagnetic Fields!
Never done this before. I wasn't thinking of a power source at this stage, just wiring them up in parallel, in the bundles of 4, and letting them sit for a day - then putting them back in series and charging them in 12.8v bundles. To be honest, I wasn't prepared for this to be so complicated. But now that I have over $2K in the batteries, I need to make it work without putting an Electrical Engineer on the household staff.

There are threads on top balancing you can read.

Connecting them in parallel won't balance them because they're not far enough up the charge curve for differences in state of charge to have much voltage difference.
If you connect them in parallel, set a CV/CC power supply to 3.65V (before connecting to batteries) then connect to batteries and let them charge until they reach 3.65V and current tapers off, then they will be balanced.

If you connect cells in 12.8V bundles and charge them, you will over-charge and bloat some cells. Unless you have connected a BMS and arranged for it to disconnect the charger.

If you don't have any supply to provide 3.65V but you do have a BMS that performs balancing, you can built the 48V pack with BMS and charge it, waiting for balancing to occur. That may take a long time (milliamps of balancing, possibly 50Ah imbalance.) You'll have to adjust charger to a low enough voltage that it limits voltage before BMS detects any cells reaching over-voltage disconnect.

If that doesn't work well, you can buy a CV/CC power supply, or just an adjustable voltage power supply wired in series with a resistor, and top off one cell at a time while it's in the 48V pack.
 

Dave Knapp

New Member
So, since these cells are already physically strapped together in packs of 4 cells, is the simplest way to proceed to get a CV/CC charger that will charge a pack of 4 cells in parallel to 3.65v. Daly's BMS instruction sheet, as terse as it is, says to connect the cells in parallel first, then in series. One of Will's videos talked to placing them in parallel and letting them sit for a day to equalize. I'm not pushing back, and I appreciate your help, but I'm looking for the path of least resistance.
 

Gazoo

Dumb Dumb
So, since these cells are already physically strapped together in packs of 4 cells, is the simplest way to proceed to get a CV/CC charger that will charge a pack of 4 cells in parallel to 3.65v. Daly's BMS instruction sheet, as terse as it is, says to connect the cells in parallel first, then in series. One of Will's videos talked to placing them in parallel and letting them sit for a day to equalize. I'm not pushing back, and I appreciate your help, but I'm looking for the path of least resistance.
Will has also posted a video explaining parallel top balancing. There are tons of resources on this forum explaining it and why it should be done. I do think if you read through Nordkyn's article it will help clear things up.

 

ken morgan

Solar Addict
So, since these cells are already physically strapped together in packs of 4 cells, is the simplest way to proceed to get a CV/CC charger that will charge a pack of 4 cells in parallel to 3.65v. Daly's BMS instruction sheet, as terse as it is, says to connect the cells in parallel first, then in series. One of Will's videos talked to placing them in parallel and letting them sit for a day to equalize. I'm not pushing back, and I appreciate your help, but I'm looking for the path of least resistance.
there are adjustable power sources on amazon for under 100 usd some even cheaper.if you do not want to take the battery packs apart, just take off the bussbars and then use the wire to connect the cells in parallel. then set the power sources for 3.4 and let it run till you have zero amps let it rest for three ro four hours between cycle. Reset for 3.5 and do same, then finally set it for 3.65. no hassels, no worries and no degree required. people like Will have put out plenty of videos. I was skeptical that it was as easy as Will claimed on line but after doing due diligence and watching many hours of videos including Will's I can say that the bugs have been pretty much worked out for us laymen. below is a link that will uses on amazon as he is in some form of affiliate program... send a little cheese his way I think. for what he lays out knowledge wise its not a bad thing.

this is the link from wills webpage: at less than 70's its a good investment I think.

 

Gazoo

Dumb Dumb
then set the power sources for 3.4 and let it run till you have zero amps let it rest for three ro four hours between cycle. Reset for 3.5 and do same, then finally set it for 3.65.
Personally I don't care for the step method. The power supply may not be able to put out the full amps it's capable of with the lower voltages even using good cables, and may not go into CC mode. I have experienced this for myself using a Riden 6012 with 12awg cables. After dealing with this when I started my top balance, I decided the heck with it and set the power supply to 3.65 volts.

I am attaching a photo of the Riden only putting out 5.84 amps with the voltage set at 3.4 volts. It is in CV mode. Once I set the voltage to 3.65 volts it put out close to 12 amps, switched to CC mode, and remained there until the voltage reached 3.65 volts. Once 3.65 volts was reached the Riden switched to CV mode and then the current began to taper off.

I also don't see anything wrong with charging each cell individually. Since each cell in the pack needs to be topped off I would disconnect the BMS if using this method.
 

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Dave Knapp

New Member
there are adjustable power sources on amazon for under 100 usd some even cheaper.if you do not want to take the battery packs apart, just take off the bussbars and then use the wire to connect the cells in parallel. then set the power sources for 3.4 and let it run till you have zero amps let it rest for three ro four hours between cycle. Reset for 3.5 and do same, then finally set it for 3.65. no hassels, no worries and no degree required. people like Will have put out plenty of videos. I was skeptical that it was as easy as Will claimed on line but after doing due diligence and watching many hours of videos including Will's I can say that the bugs have been pretty much worked out for us laymen. below is a link that will uses on amazon as he is in some form of affiliate program... send a little cheese his way I think. for what he lays out knowledge wise its not a bad thing.

this is the link from wills webpage: at less than 70's its a good investment I think.

Thanks for the encouragement. I'm in the Philippines, so Amazon is a little harder to do. I found a LifePO4 3.65v charger online here and just ordered it. It says it is specifically for LIfePO4 batteries. I was hoping that it would do the voltage control automatically since that appears to be the issue with this chemistry. I may have to baby sit it. I can do 8 bundles of 4 cells in parallel. Probably take a week. I'm retired, so I got the time. Might need to set up a fridge in my shop. Thanks again. I sounds less painful your way.
 

Dave Knapp

New Member
Will has also posted a video explaining parallel top balancing. There are tons of resources on this forum explaining it and why it should be done. I do think if you read through Nordkyn's article it will help clear things up.

Thanks for the reply. The article is not in favor of bottom balancing, so I caught in the middle there. My plan is to use a LiFePO4 charger to charge each 4p bundle to 3.65v. Then put them back in series for 12v packs and assemble to bank (16s,2p) and the BMS and hopefully it will work.
 

ken morgan

Solar Addict
Thanks for the encouragement. I'm in the Philippines, so Amazon is a little harder to do. I found a LifePO4 3.65v charger online here and just ordered it. It says it is specifically for LIfePO4 batteries. I was hoping that it would do the voltage control automatically since that appears to be the issue with this chemistry. I may have to baby sit it. I can do 8 bundles of 4 cells in parallel. Probably take a week. I'm retired, so I got the time. Might need to set up a fridge in my shop. Thanks again. I sounds less painful your way.
Howdy neighbor! I am "semi retired" here in Japan. You could order the same charger I bought from aliexpress and they ship worldwide. it is the non adjustable type. 3.65 volts constant voltage type. it maxes at 14 amps until it hits 3.65 and then it drops the amps until it is done. real simple user friendly but slow as a platoon of privates on a work detail.


its only 54 USD but its currently on sale. for 40.00 and will take care of your issue, just take off your bussbars and then hook it to one battery at a time. let it run till the green light comes on. slow but guaranteed.

S/F

Ken
 

Zwy

Solar Addict
Thanks for the reply. The article is not in favor of bottom balancing, so I caught in the middle there. My plan is to use a LiFePO4 charger to charge each 4p bundle to 3.65v. Then put them back in series for 12v packs and assemble to bank (16s,2p) and the BMS and hopefully it will work.
Get a BMS, hook them in series until one cell hits 3.5 to 3.65V. Then go to parallel charging to balance them. Much faster.
 
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