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Top balancing clarification.

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Dec 14, 2019
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I did a quick search and didn't find the answer I was looking for.
I have 16 lishen 272ah batteries that are new. I'm currently off grid on solar.
I need to top balance. My batteries are all at 3.26v.
I watched wills video on top balancing and he spoke of using a conventional battery charger.
Can I use any battery charger to get them close?
Then switch to parallel and use the power supply wills video recommended to use to finish topping off to 3.65v.
I want to use a smart charger used in automotive. Is that ok? Picture attached
Any knowledge you could share id be greatful for.
By the way the only BMS I have is a 48v daly. I do not have a 12v bms.
Also how long would it take to charge each pack using this battery charger set to 40 amps.
I'm still trying to learn c rating. But my lead acid pack is dieing and I don't have alot of time to fully grasp it.
Thankyou everyone. I really appreciate any help I get.
 

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Download the guide. Read it:


Do not deviate from the above. If you attempt to charge in series without a suitable BMS attached, you run an extreme risk of killing cells.

Since you only have a 48V BMS, you can only series charge with 16 cells, i.e., you can only charge at 48V.

You could use your charger if you obtained a cheap 12V bms. You could wire them 4P4S and charge them as a 12V.

You would then top balance by putting all of them in parallel and charging with a bench top power supply per the guide.
 
Download the guide. Read it:


Do not deviate from the above. If you attempt to charge in series without a suitable BMS attached, you run an extreme risk of killing cells.

Since you only have a 48V BMS, you can only series charge with 16 cells, i.e., you can only charge at 48V.

You could use your charger if you obtained a cheap 12V bms. You could wire them 4P4S and charge them as a 12V.

You would then top balance by putting all of them in parallel and charging with a bench top power supply per the

How are you planning to charge them when in operation?
I have solar. But was hoping to get started on top balancing while waiting for my 3 replacement cells to come in.
Guess I'll just wait for them to get here then put them in 16s and use solar to push them most of the way up. Then switch to parallel and use my power supply.
Is what it is.
 
Download the guide. Read it:


Do not deviate from the above. If you attempt to charge in series without a suitable BMS attached, you run an extreme risk of killing cells.

Since you only have a 48V BMS, you can only series charge with 16 cells, i.e., you can only charge at 48V.

You could use your charger if you obtained a cheap 12V bms. You could wire them 4P4S and charge them as a 12V.

You would then top balance by putting all of them in parallel and charging with a bench top power supply per the guide.
Ty I was hoping to save time. But sometimes we just don't get what we want. Is what it is.
I'll wait for my 3 replacement sells and then use solar to charge them most of the way with bms. Then top balance with power supply. Thankyou snoober
 
You wouldn't save much time. I would expect you can top off the 48V in a day of good sun. If you plan to parallel the banks to get the LFP charged, make sure they're close in voltage. 0.2V should be close enough.
 
Hey guys
Got my replacement batteries.
I'm still running mismatched pack. But there all 272ah. Biggest difference is the studs. But he has 16 brand new matching batteries on order to swap out these 16 with. Plus ill be ordering another 16 of the same cells to make 32 cells.
My plan is to get a total of 64 at a minimum. We truly want 128 and in time will reach that goal. But heres some pics of my temporary setup.

And we had our baby on 5/29/21 a boy of 6 pounds 11oz. 18 1/2 inch long. Before him we lost 2 babies. So pardon the excitement.

Also a bit of info on my system
*Growatt spf 6000t dvm hybrid inverter charger
*20 solan blu 230 watt P.V. panels
*And not 16 lishen 272ah batteries.
*A epever tracer 48v 150vdc pv input (backup controller)
 

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With all that on order I would charge them in series with BMS connected and just use them until the next set comes in. keep them at 30% to 70% and there should not be any immediate balance issues. As the other cells come in, get them top balanced and swap the new stack into service. Then you can worry about getting the first set fully squared away. Not perfect but that is what I would be looking at if it was a squeeze on time. The first series set could be on line tomorrow.
 
You could use your charger if you obtained a cheap 12V bms. You could wire them 4P4S and charge them as a 12V.

You would then top balance by putting all of them in parallel and charging with a bench top power supply per the guide.

A cheap 12v BMS that will accept 10 amp charge rate is an excellent suggestion.

Be careful of that one, I am not sure that you can change the presets, which are 3.75v overvoltage, and 3.65v overvoltage release. Those are actually quite common values for cheap Chinese BMS. Likely 3.75v won't damage your cells, but we need to find a good one that is set for 3.65v to recommend.
 
20 solan blu 230 watt P.V. panels
*A epever tracer 48v 150vdc pv input (backup controller)
Have you considered creating 2 arrays and both SCC's? One facing east-ish and one facing west-ish would extend your solar charging day by starting charging earlier (east) and later (west). Also, you would have redundancy build in and running rather than having your epever as a spare. Just a thought.
 
Have you considered creating 2 arrays and both SCC's? One facing east-ish and one facing west-ish would extend your solar charging day by starting charging earlier (east) and later (west). Also, you would have redundancy build in and running rather than having your epever as a spare. Just a thought.
I just purchased a 2nd growatt. This time a spf 12000t dvm map.
Has 2 solar inputs and allows for 250v pv input.
Being off grid and a prepper I believe that you need backups for you backups. The epever with get me by in a pinch. Well ounce fixed.
 
Hey guys
Got my replacement batteries.
I'm still running mismatched pack. But there all 272ah. Biggest difference is the studs. But he has 16 brand new matching batteries on order to swap out these 16 with. Plus ill be ordering another 16 of the same cells to make 32 cells.
My plan is to get a total of 64 at a minimum. We truly want 128 and in time will reach that goal. But heres some pics of my temporary setup.

And we had our baby on 5/29/21 a boy of 6 pounds 11oz. 18 1/2 inch long. Before him we lost 2 babies. So pardon the excitement.

Also a bit of info on my system
*Growatt spf 6000t dvm hybrid inverter charger
*20 solan blu 230 watt P.V. panels
*And not 16 lishen 272ah batteries.
*A epever tracer 48v 150vdc pv input (backup controller)
well it looks like ya got a partner in crime now! Congrats.

Is that an actual DALY or a clone? it uses the same software as mine did so I was curious. I get a little drift between cells when charging up closer to the knees. 2P16S basically I have two one 2p cells that runs a little faster to full, and one 2P cell that lags in regards to the others. I was considering breaking the pack up and swapping one each of the cells to each other to see if I could narrow the range of drift.

edit, noticed it was a daly in earlier comments.

R

Ken
 
Last edited:
Hey guys
Got my replacement batteries.
I'm still running mismatched pack. But there all 272ah. Biggest difference is the studs. But he has 16 brand new matching batteries on order to swap out these 16 with. Plus ill be ordering another 16 of the same cells to make 32 cells.
My plan is to get a total of 64 at a minimum. We truly want 128 and in time will reach that goal. But heres some pics of my temporary setup.

And we had our baby on 5/29/21 a boy of 6 pounds 11oz. 18 1/2 inch long. Before him we lost 2 babies. So pardon the excitement.

Also a bit of info on my system
*Growatt spf 6000t dvm hybrid inverter charger
*20 solan blu 230 watt P.V. panels
*And not 16 lishen 272ah batteries.
*A epever tracer 48v 150vdc pv input (backup controller)
FYI, that Bluetooth dongle you got in the picture there is one of the new ones that has a "wake up" button on it. The black dot to the right of "Bluetooth" is it.
 
well it looks like ya got a partner in crime now! Congrats.

Is that an actual DALY or a clone? it uses the same software as mine did so I was curious. I get a little drift between cells when charging up closer to the knees. 2P16S basically I have two one 2p cells that runs a little faster to full, and one 2P cell that lags in regards to the others. I was considering breaking the pack up and swapping one each of the cells to each other to see if I could narrow the range of drift.

edit, noticed it was a daly in earlier comments.

R

Ken
Honestly I think it's a clone. Every daly iv seen says it on the bms. This just has a big bms sticker. But it seems to work.
I'm going to bottom balance these sells. And hope to live between 20 and 80% till my replacement pack comes and my 16 matching.
I just pulled the trigger on jumping to 16s 2p. 32 cells and 28kwh should be nice.
 
Honestly I think it's a clone. Every daly iv seen says it on the bms. This just has a big bms sticker. But it seems to work.
I'm going to bottom balance these sells. And hope to live between 20 and 80% till my replacement pack comes and my 16 matching.
I just pulled the trigger on jumping to 16s 2p. 32 cells and 28kwh should be nice.
Good Luck especially with the little one about. before you know it he will be running amuck and stealing your bourbon :)
 
also the programyou showed on your cell phone is the DALY bluetooth program. it allows to change the upper and lower cutoffs. you should really set you solar to stop at about 54.4 and then set the BMS to cut off at 58 for the pack and 3.60 for the individual cell that will cover the top end without the BMS constantly shutting of your charge or discharge. (54.4 is 3.4 per cell) then set your inverters to shut off at a higher voltage than the BMS this will turn the BMS into your second line of defense for your batteries with your SC and inverter being the first lines.
 
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