Other Parts Discussed in Thread: BQ76942, BQ34Z100, GPCCHEM
Tool/software:
Hi, We've Just attempted our first learning cycle with our Battery Management Configuration of a BQ76942 & BQ34z100-R2, We followed the process and ended up with a failed cycle with Learned Status stuck as 0x05.
Now there are a couple of things that I've noticed are wrong that I would hopefully like some clarity on. The main thing is the voltage calibration of the Chip. There doesn't seem to be anything about this on the datasheet or technical reference manual but since we have 7 cells in series, when we go to calibrate the voltage it multiplies the calibrated voltage by 7. Should be dividing the value by 7 and then calibrating? or should be calibrate it at stack voltage and then change the Volt Scale value to be 7 to get the correct reading out?
The second big problem is that when charging and discharging after calibration the Voltage will slowly follow the Battery Voltage lagging behind by quite a bit, but after around 20-30 minutes the voltage will get 'stuck' and just not move for the rest of the charge/discharge. This is obviously going to cause an error in the Learning Cycle I would assume. If you've seen any cases similar to this you could point in our direction that would be a brilliant help.
Finally I've failed to find anywhere that specifies on what to do after a learning cycle has failed. Whats the recovery method to go back and start a new Learning Cycle?
Sorry for all the questions in the same post but appreciate all the help and support.
Kind Regards,
Rhys Philllips