BQ40Z50:When charging with BQ24765 charger, RSOC JUMP and FCC drop

For other PACKs that applied the same SREC file to the same charger, we confirmed that FCC and SOH were applied normally and EOC Voltage was also within the normal range. Is there a reason why this phenomenon occurs intermittently in the Pack?

Hello Jang,

-Is this an normal occurrence for SOC to jump sharply, or was this just a one time occurrence? 

-If this is a normal occurrence please attached your GPPCHEM report files you gotten for your chemID selection. 

Thank you,
Alan

We are doing cycle tests with many PACKs.
Sometimes, when the SOC increases rapidly and the SOH and FCC decrease, the packs return to normal when cycled again.
However, this problem becomes bigger when the quantity increases in the mass production stage.

Hello Jang,

Based on the last response I am interrupting this as a normal occurrence (please emphasize if it is or is not) but I am going to ask for these files from your side.

-Attach your GPCCHEM report files that you gotten for your chemID selection

-Confirm what your update status is showing, example below 

-Attach .gg file for review, along with battery cell datasheet and pack configuration

-Lastly in the meantime please do a calibration within the calibration tab and pleas confirm that your not using differently aged cells along with having cells that aren't different.

Thank you,
Alan

This is an abnormal phenomenon. In some cases, it returns to normal when the charge/discharge cycle is repeated, but the cause is unknown.

If you did not use the GPCCHEM report file, the ChemID is SAMSUNG-INR18650-35E, and the update status is 0E. You did not use aged cells. The number of cycles is less than 10. For reference, the gg file and cycle logging data are attached.

LI18S01_20250227_0e.gg.csv4571.test.gg.csv

Hi Jang,

Can you please confirm that the TEST2GG.gg.csv was pulled from the device after the charge/discharge cycling? If so, can you please share a .gg file taken after charge/relax/discharge of a functioning pack at this time? The FCC is greatly dependent on the resistance tables, to where this will allow us to compare if there are any differences between the two.

Regards,

Anthony

Hi Anthony

I have a new fact about the FCC fluctuation.

It is that the FCC changes immediately after the end of the charge cycle, not during the charge and discharge cycle.

I don't think the RA Table Update is related to the current issue, as it is updated during the discharge.

Can the FCC change lower if the Pack ends at a lower point than the set voltage?

Would fixing the RA filter to 1000 solve this problem of charge voltage instability?