Other Parts Discussed in Thread: BQ27426
Dear all,
I am developing a new design with LiFePO4 batteries and I am using the bq34z100-g1 to estimate SoC and SoH of the battery.
I have use the GPC tool to find the best CHEM ID, did the procedure shown in SLVA725 document (with bigger relaxing times) and this is the report
1738.GPC_report.txt
Chemistry ID selection tool, rev=2.42 Configuration used in present fit: ProcessingType=2 NumCellSeries=8 ElapsedTimeColumn=0 VoltageColumn=1 CurrentColumn=2 TemperatureColumn=3 Best chemical ID : 414 Best chemical ID max. deviation, % : 5.59 Summary of all IDs with max. DOD deviation below 15% Chem ID max DOD error, % Max R deviation, ratio 0 0 0 Max. deviations for best ID is within recommended range. Chosen best chemical ID is suitable for programming the gauge. Selection of best generic ID for ROM based devices like bq274xx Device / Family #1 Generic Chem ID Device/ Voltage/ Chemistry max DOD error, % 354 bq27411-G1C: 4.35V LiCoO2 42.54 3142 bq27421-G1D: 4.4V LiCoO2 59.26 312 bq27421-G1B: 4.3V LiCoO2 97.59 128 bq27421-G1A: 4.2V LiCoO2 9936.53 Best generic ID 354 Warning: Generic ID Deviation is so high that it is most likely due to anomaly in the data. Please check that data files have recomended format, units and test schedule Device / Family #2 Generic Chem ID Device/ Voltage/ Chemistry max DOD error, % 1202 bq27621: (default) 4.2V LiCoO2 41.44 354 bq27621: (ALT_CHEM2) 4.35V LiCoO2 42.54 1210 bq27621: (ALT_CHEM1) 4.3V LiCoO2 48.22 Best generic ID 1202 Warning: Generic ID Deviation is so high that it is most likely due to anomaly in the data. Please check that data files have recomended format, units and test schedule Device / Family #3 Generic Chem ID Device/ Voltage/ Chemistry max DOD error, % 3230 bq27426: (default) 4.35V LiCoO2 30.79 1202 bq27426: (ALT_CHEM1) 4.2V LiCoO2 41.44 3142 bq27426: (ALT-CHEM2) 4.4V LiCoO2 59.26 Best generic ID 3230 Warning: Generic ID Deviation is so high that it is most likely due to anomaly in the data. Please check that data files have recomended format, units and test schedule Warning: First OCVpoint has non-zero current I= -0.003 Please make sure you have a 2 hr relaxation period before the beginning of discharge. Warning: Last OCVpoint has non-zero current I= -0.002 Please make sure you have a 5 hr relaxation period after the end of discharge.
I have some questions about it:
- I understand best chemical ID suites my LiFePO4 battery is 414. Is this correct?
- What about other Chem ID mentioned in the document for other devices (bq27411, bq27621, bq27426)? I have no intention of using any other device.
Thanks,
