Part Number:BQ40Z50-R1
I have completed a full ChemID Cycle (partial charge, relax, discharge, relax), following the instructions in http://www.ti.com/lit/an/slva725a/slva725a.pdf. The only deviations from the instructions were that the relax periods were significantly longer than 2hr post charge and 5hrs post discharge specified (battery left to relax overnight).
The log file from this that I submitted to GPCCHEM was:
/cfs-file/__key/communityserver-discussions-components-files/180/chem_5F00_id_5F00_testing.zip
and the report received:
As you can see in the report, the recommended ChemID is 1582. As shown in the screen cap from bqStudio below, this is listed as a 1920mAh model. I do not have the exact chemistry of the cell under test, but I do know it is ~5400mAh, which is significantly different. Does the difference in capacity matter for Chemistry ID? Should I disregard the result and try again, or trust the matching tool?!
I ask because when subsequently running a learning cycle the learning cycled failed during the discharge stage with RDIS and NSFM bits set. From https://e2e.ti.com/cfs-file/__key/communityserver-discussions-components-files/180/7418.Achieving-The-Successful-Learning-Cycle.pdf, common failure number 6 states
Which I would not expect as I have just applied the ChemID matched by GPCCHEM. I have confirmed that the ChemID was applied correctly with SMBus command 0x6, and I reset the bq40z50-R1 prior to starting the learning cycle to ensure the update was 'applied'.
My questions are:
- Is the matched Chemistry ID implausible given the large difference in capacity between the cell under test and the model listed in the chemistry database?
- If so, can you see what in the submitted log file is causing the problem and how I might fix this?
- If not, what else can I try to successfully complete a learning cycle?
- How could I verify that I have an appropriate Chemistry ID, other than by running a learning cycle and not getting RDIS set?
Thanks,
Hamish
