BQ34Z100: LTO battery cells chemistry

Part Number: BQ34Z100

Hello,

We have developed an electronic module using the BQ34z100 gauge circuit with LTO cells. I need to find out the chemistryID or other parameters required for accurate battery state measurement.

The schematics of open-source module SOLARMINIBAT01 is available here, in the repository.

We tried to obtain the chemistryID based on the online estimator from measurements taken with the TI battery gauge programmer. However, we received an empty report from the online estimator, and it couldn't determine the chemistryID from our measurements.

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0   0   0
0   0   0
0   0   0
0   0   0
0   0   0
0   0   0
0   0   0
0   0   0
0   0   0
0   0   0
0   0   0
0   0   0
0       
        
Summary of all IDs with max. DOD deviation below 3%     
        
Chem ID max DOD error, %    Max R deviation, ratio
0   0   0
        
Warning: Deviation is above recommended level. New chem ID needs to be released for this cell. Please contact your TI representative to send the cell to Dallas for characterization        
        
XXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXX

0	0	0
0	0	0
0	0	0
0	0	0
0	0	0
0	0	0
0	0	0
0	0	0
0	0	0
0	0	0
0	0	0
0	0	0
0		
		
Summary of all IDs with max. DOD deviation below 3%		
		
Chem ID	max DOD error, %	Max R deviation, ratio
0	0	0
		
Warning: Deviation is above recommended level. New chem ID needs to be released for this cell. Please contact your TI representative to send the cell to Dallas for characterization		
		
		
Selection of best generic ID for ROM based devices like bq274xx		
		
		
Device / Family #1		
Generic Chem ID	Device/ Voltage/ Chemistry	max DOD error, %
312	bq27421-G1B: 4.3V LiCoO2	200
354	bq27411-G1C: 4.35V LiCoO2	200
3142	bq27421-G1D: 4.4V LiCoO2	200
128	bq27421-G1A: 4.2V LiCoO2	200
Best generic ID 312		
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, %
1210	bq27621:  (ALT_CHEM1) 4.3V LiCoO2	200
354	bq27621:  (ALT_CHEM2) 4.35V LiCoO2	200
1202	bq27621: (default) 4.2V LiCoO2	200
Best generic ID 1210		
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	100
3142	bq27426: (ALT-CHEM2) 4.4V LiCoO2	200
1202	bq27426: (ALT_CHEM1) 4.2V LiCoO2	200
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=  -0.01 Please make sure you have a 2 hr relaxation period before the beginning of discharge.		
Warning: Last OCVpoint has non-zero current I=  -0.016 Please make sure you have a 5 hr relaxation period after the end of discharge.		
Warning: Discharge rate is too high. High rate reduces ID detection accuracy	 10 hr rate is recomeended. Total discharge time is less than 5 hrs	 t_hrs=  3.64923638888889

Is it possible to determine the chemistryID based on, for example, the datasheet or some detailed cell parameters?

We have used this batteries: https://files.gwl.eu/inc/_doc/attach/StoItem/7015/GWL_LTO1865_Rechargeable.pdf

Thank you.

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BQ34Z100: LTO battery cells chemistry