Good morning,
I'm using the BQ34Z100-G1 for a NiMH 24S1P battery pack (BK1100FHU cells).
A first problem is the allowed range of the parameter "Cell Terminate Voltage": 1V as a minimum value is definitely too high for a NiMH cell in several conditions: it means the SOC value is reset too early, i.e. when the average single cell voltage reaches the 1V value during a discharge cycle. I would suggest to extend such a boundary value to 0.8V.
But this is not my currently issue. In fact the "strange" behaviour appears at full charge. I've disabled the SOC threshold mechanism for setting the FC flag (i.e. "FC Set %" = -1) and also the dV/dt mechanism has been disabled (i.e. "NI DV" = 0 in "Pack Configuration" register); so only when dT/dt curve overcomes the proper threshold, this should happens: Flags[FC]=1; Flags[CHG]=0 and Pack Configuration[RMFCC]=0 (as pointed out on page 37 of the datasheet).
In my case that sometime doesn't happen.
So I would like to ask some clarifications about the dT/dt detection algorithm:
- is that based on moving window (i.e. each new temperature value is compared to the value measured "NiMH Delta Temp Time" before) or thet comparison is done after each "NiMH Delta Temp Time" intervals (i.e. a undersampling of the temperature array)?
- are temperature values obtained from single measures or are them averaged values? How are they averaged (just in case)?
- is there any other enabling condition for applying the dT/dt criteria?
in attachment you can find the config file I'm using.
Thank you very much for any support
Best regards
Matteo
