Hello everyone,
we have successfully set up a 24V LiFePo4 battery pack with the BQ34Z100 chip, i.e. charged, recharged, got Qmax updates, update status = 0x06.
Now here's the problem: During setup, we used a charger that came with the pack, which charges it to a whopping 28V. During operation however, the pack is charged by a solar MPPT tracking charger which finishes charging at 26.8V. When we had the battery in place with the solar charger and our system, charging and discharging randomly, the SOC suddenly started jumping from 100 to 0 in a load situation and back to 100 in a relaxing condition. The update status remains at 0x06, but we have noticed that the FCC has made a huge jump from initially (after learning) ~28000mAh to around 6000mAh (see attached screenshots which were taken after).
My first guess is that some setting about charge voltage and taper voltage is wrong, but we're not really sure what to set it to - the end charge voltage of the MPPT charger or the wall charger? We would like the FC flag to trigger so as to have some indication that the MPPT tracker has finished charging.
Could one of you help us figure out what's wrong? I have attached all the information from the system we were able to extract (it's a few hundred km away from here, so we don't have live access)
Simon Harst
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