TI中文支持网用bq40z50-R1做-40度低温GPCRB补偿，上传压缩数据后，TI返回的GPC_report指出Error: negative room temperature resistance observed
报告全文如下
Resistance temperature compensation optimizer, rev=3.38Optimized Impedance Track parameters:Qmax, mAh : 15990Ra table normalized to 25C, uncompressed, unscaledDOD, % Ra, mOhm0 1611.11 1622.22 2133.33 3044.44 1255.56 1666.67 1477.78 2380.95 3784.13 5587.3 5390.48 7593.65 6196.83 134100 245Ra0_ch, mOhm : 105 This firmware is not explicitly supporting Ra0_ch, FCC drop could occur at low temperatures if usedThermal parameters:Temp a 379Temp k 0.04Optimized resistance temperature compensation parameters saved in chemdat12All GG values updated and saved in gg_out.csvError: negative room temperature resistance observed R=-0.00219277680472831 usually caused by wrong chem ID selection
请问化学ID的问题在那里？
电池的化学ID也是用GPC获得的，报告全文如下
Chemistry ID selection tool, rev=2.47Configuration used in present fit:ProcessingType=2NumCellSeries=4ElapsedTimeColumn=0VoltageColumn=2CurrentColumn=3TemperatureColumn=1Best chemical ID : 2125 Best chemical ID max. deviation, % : 1.43Summary of all IDs with max. DOD deviation below 3%Chem ID max DOD error, % Max R deviation, ratio
2125 1.43 0.44
2112 1.67 0.84
2046 1.94 1.21
2250 1.95 0.91
2162 1.98 0.4
2039 2.07 1.16
2050 2.11 1.42
2133 2.13 1.25
2158 2.16 1.28
3758 2.18 1.03
2101 2.36 1.81
2142 2.79 1.42
2141 2.84 1.44
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 #1Generic Chem ID Device/ Voltage/ Chemistry max DOD error, %
3142 bq27421-G1D: 4.4V LiCoO2 17.58
354 bq27411-G1C: 4.35V LiCoO2 19.27
128 bq27421-G1A: 4.2V LiCoO2 100.04
312 bq27421-G1B: 4.3V LiCoO2 108.59
Best generic ID 3142Warning: 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 #2Generic Chem ID Device/ Voltage/ Chemistry max DOD error, %
354 bq27621: (ALT_CHEM2) 4.35V LiCoO2 19.27
1210 bq27621: (ALT_CHEM1) 4.3V LiCoO2 19.91
1202 bq27621: (default) 4.2V LiCoO2 20.4
Best generic ID 354Warning: 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 #3Generic Chem ID Device/ Voltage/ Chemistry max DOD error, %
3142 bq27426: (ALT-CHEM2) 4.4V LiCoO2 17.58
3230 bq27426: (default) 4.35V LiCoO2 19.3
1202 bq27426: (ALT_CHEM1) 4.2V LiCoO2 20.4
Best generic ID 3142Warning: 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
Star Xu：
报告提示在低温度放电过程中，加载电压在某一时刻高于您选择的ID中的OCV(卸载开路电压)。
If GPCCHEM gave you other chemIDs which were also reasonable matches, you can try to run GPCRA and GPCRB with those chemIDs instead and see if you do not get the error. You can also try to use a slightly higher current during the low temp discharge to ensure the voltage drops below the OCV voltage.
