• State Resolved
  • Locked Locked
  • Replies 2 replies
  • Subscribers 63 subscribers
  • Views 367 views
  • Users 0 members are here
Support feedback
Options
Options
Related

This thread has been locked.

If you have a related question, please click the "Ask a related question" button in the top right corner. The newly created question will be automatically linked to this question.

bq20z45 SOC does show correct value after enabling IT.

ken thompson
Intellectual 630 points
Other Parts Discussed in Thread: BQ20Z45

We load our golden .DFI file, calibrate, attach cells at 1/2 SOC, reset, wait 5 minutes and enable IT.  All is done per SULA391.  SOC shows 3%.  At what point does IT look at OCV and correct SOC?

The only way we have found to correct SOC is to totally discharge the cells, reset the bq20z45 and recharge the cells.  This takes too long for production.

Ken

  • 0
    Intellectual 630 points

    Last night I tried the suggestion of setting the charge taper current up to just above our charger’s cut off current of 100mA.  Tried 110mA.

    The factory .DFI file was loaded, a new .GG file imported and a new golden .DFI saved.  It was reloaded, the board calibrated and a half charged set of cells connected.

    0% SOC was shown and max error 2%.  Then the cells were fully charged.

    It was expected that when the taper current got below the threshold setting of 110mA that SOC indication was supposed to go closer to 100%.

    It did not. It shows 30%.

    So changing this parameter had no affect toward resolving our SOC issue at assembly time.

    Again it was my impression that the IT system looked at SOV after of relaxed cells toward indicating SOC.  So far all I see effectively happening is coulomb counting.

  • 0 in reply to ken thompson
    Prodigy 5 points

    This issue was resolved by using the correct CHEM ID.

    Without the correct battery chemistry, the impedance track algorithms will not work correctly.