Hi, is there anyone that knows where i can find sofware to edit my 48v 100ah lifepo4 narada parameters. My system was installed in 2019, and only last year I got software to monitor the cell voltages(ICM). My problem is that the bms is not controlling the cell voltages. If i charge say with 20A, some cells go over voltage and the bms is too slow to prevent it. All my cells is now damaged, I have replaced 4 cells so far, in the picture you can clearly see which 4 (2,3,4,5). Now cell 6 and 9 sometimes goes up to 3.8v before the bms stops the charging. I do not know what the parameters is in the bms!
To me it seems as if you have a low cell problem rather than a high cell problem. You have 4 cells at 3.4V.
The rest are all above 3.5V and doing just fine. A cell at 3.8V is high, very high, and long term not good for it, but it won’t damage the cell, at least not immediately. Many production BMSes only start to intervene around that point.
I have a wild idea. Based on theory and not practice, but since you’re replacing cells it is worth a shot.
Shuffle your cells. Alternate high and low cells.
Let me explain. Most balancers are passive balancers. They work by bypassing current past a cell. They are also interleaved, which means that they alternately bypass the odd-numbered high cells, and then the even-numbered high cells. When you have several low cells right next to each other, balancing is hard. In this example, charge has to be bypassed past cell 1 into cell 2, but cell 3 cannot be pulled up until cell 2 has a decent amount of charge to work with, and cell 4 cannot be pulled up until cell 3 has been pulled up.
By shuffling the cells so they are all in even/odd positions, I have a feeling you might speed up the balancing. Assuming that works at all.
I know I am not really answering the question, which was for the software.
@OROS
Did you manage to sort out something?
You have SOC drift. 100% soc with 60AH capacity, hmmm.
And then the cell high and low difference is huge.
Possibly the system is not charging to and holding the system voltage where the bms balances the cells.
Set system to keep batteries charged, charge up with low amps and then do the check again.