Daly BMS Not Balance Charge only one cell

[NosHolley]

Hi!
I bought a Daly BMS for Lifepo4 4s 60A months ago. My aim is a 105Ah battery pack for caraudio. I performed the installation as shown in the diagram, and tried to charge the battery pack for the first time. After a few minutes, the system goes into lockout due to over voltage of the first cell. As if the system fails to budget. This happens regardless of the charging current, only the time in which it locks up changes.
Another strange thing, the system gives me the batteries charged, so SOC 100%, but the voltage of the single cell with is that of maximum charge, as you can see in the image.

Do you have any ideas?

Thank you

 

[NosHolley]

These are the settings

 

[TacomaJoe]

Did you top balance the cells before building the 4S? Doesn't look like it with cell #4 way up there. You can put a load on cell #4 to draw it down, then try a charge cycle. If you keep doing that, you may get close to balanced. I'd top balance the pack.

 

[NosHolley]

It was the first thing I did once I saw the problem. But as soon as you charge the battery pack, the problem returns. I point out that the imbalance was created by the bms, because the cells were balanced and new.

 

[TacomaJoe]

Did you load the battery or the cell to bring it down? Cell #4 is the trouble maker not the BMS. The BMS is doing it's job with cell overvoltage shut down. Put on a load and run the battery down to 50% SOC and watch your cell voltages to see if #4 moves closer in voltage to the other cells.

 

[stuggi]

@NosHolley I see the same behavior. Started from balanced set of batteries. Wondering if the issue is fixed for you?

 

[NosHolley]

Hi, I solved using the voltage values proposed here, which are the realistic ones of the lifepo4 cells.

LiFePO4 Voltage Chart?

Hi guys, I was looking through the mobile-solarpower.com website, and on this page I found a battery voltage chart for LiFePO4 batteries. But I noticed it wasn't showing the exact voltage ranges that my battery data sheet does. My data sheet shows 100% charge at 14.6V and 0% charge at 10.0V...

diysolarforum.com

 

[stuggi]

Thank you very much for the fast response. Will check that thread.