How to determine if balance current is good enough

How many cell in parallel can v4 handel

As many as you want, parallel cells just act like a single large cell. What you need to calculate, is the balance load of the module suitable for the capacity of all those cells?

@stuart If I have two packs with 16 cells each (two 48V pack in parallell), can that be handled with one module44 per battery (32 batteries) and one controller?
Or do I need one controller per battery pack?

Yes - one controller and 32 modules needed for this configuration. You would configure the controller with 16 series cells and 2 banks/packs.

How can i calculate the balance load of the module

Please is it the power supply to the ESP that is also used in charging the battery from each module

Please i did not get a response to my question

It depends - only you can determine that, based on what cells you are using, the total capacity, are they second hand, chemistry etc.

Its not an exact science.

try doing this, do i have to change some component on the module to achieve this

You dont have to change anything on the modules. The modules itself have a static load and instead uses pwm to decrease balancing when getting warm and so forth.
The only thing you need to consider is if your battery bank is old or weak and goes out of balance quickly and need more balancing power than the modules can supply. For most systems a cell module like this can easily handle 200-500+Ah cell bank.

BUT note that you dont balance 24/7. You generally only balance when the battery bank is full and lets say thats 4 hours per day so you basically only get around 3-4Ah balanced per day. So if your battery bank is off by 50Ah it takes 10+ days to balance that out. Then its important that the battery doesnt fall out of balance faster than it can correct it.

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Am a novice please give me an example

Please can anyone tell me how to calculate the balance load of the module with an example :sob: :sob: :sob:

Divide the total voltage going into the full balance resistance BY the total resistance, and you will get the current/amps value.
If you change the resistance value, you will change the amps value,
Too low a resistance value and you will burn up the board.

Li-Ion BMS - White Paper - How much balancing current do you need? here you find information they helps you in understanding balance current.

There is also a different approach that was successful for me in the past. Balancing during charge cycle, that mains you can try to balance out cells with a big difference by passing the charge current over the cell. You put your pack in CC charging and make the balance current the same value as the CC this way cells in bypass will not charge and only cells that are not in bypass will charge. It works but you will dump a large amount of energy

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Balancing current is only important if 1 or more banks is not equal, this will happen as the bank ages, more voltage between the packs the bigger the balancing current needs to be

To all, who contributed to my QUESTION, GOD BLESS YOU.
Have learned…

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