Other Parts Discussed in Thread: BQSTUDIO
Hi,
I think I did not understand completely the SoC algorithm in the bq78350-r1.
First thing:
1) SoC is completely wrong after a reset of the device. I use a Samsung 50E 21700 cell. In your chemistry I found it and I did program this with (Program selected chemistry) in bqstudio. But for example, if all my cells are nearly full (above 4.1 V) and I do a reset, it resets the SoC to 53 %. Why and how can we change that ? Do I have to program the OCV curve somehow by myself ? Or is there some kind of command to set the SoC? Because it would be nice to set the correct SoC in production.
2) In my application there can be current peaks, 30 seconds long up to 13A (on a 14s1p configuration). So the voltage drops significantly for example on a fully charged battery from 4.2V to 3.7 V with 13A. But as far as I understood this should not be a problem, because the fuel algorithm calculates an Compensated End of Dischrage voltage, which should take the applied current into account. I attached a log. You can see in this log, that the SoC is reset from 41 to 7 percent. But not during high load (13A). It is reset after the high load, during low load. This is because the cell voltage need a couple of seconds to recover again. But in the meantime, the pending EDV switched back from (something 2.7V what I saw) back to 3.5V. And so the condition was fulfilled. So the question is: Is there a setting, which will increase the time evaluation for the EDV pending value ?
Thanks in advance.setting_1505_lab.gg.csv
Paul