BQ27Z561EVM-011: Sens Resistor Change

Hello,

I have a question about Current Calibration.

The bq27z561 is 1mohm (TRM says CC Gain is 0.1mOhm to 4mOhm).

I'm trying to make it 20mOhm. The CC Gain is out of range.

Is this okay? How high can the resistor be?

Regards.

I know about the 1mΩ to 3mΩ thing.

However, after seeing SLUA792, I'm giving it a try.

I reviewed the settings again and tried again, creating a golden image at 20mΩ.

Please take a look at the logs.

・Sample No. 2025 (2024/7/3 10:04:30) and No. 2026 (2024/7/3 10:05:00)

・Sample No. 20252128 (2024/7/3 10:56:01) and No. 2129 (2024/7/3 10:56:31)

The AutoExport GG file is also attached.

001.gg.csv (Update Time: 2024/7/3 10:02)

002.gg.csv (Update Time: 2024/7/3 10:07)

003.gg.csv (Update Time: 2024/7/3 10:52)

004.gg.csv (Update Time: 2024/7/3 10:57)

FCC has changed drastically.

In the catalog sheet of bq27z561, it is 1mA to 5A.

Charging current is 200mA, and 4A for x20, which is included in the specs.

There is no significant change even when looking at the GG files before and after.

I can't find the cause even when looking at the log or the gg file.

However, I think that this problem can be solved by changing some setting.

7026.LogFile.zip

Hello, 

Please expect a delayed response while I review what you have sent over. 

Regards, 

Jonny.

Hello,
Has there been any progress?
I look forward to hearing from you.
Regards.

Hello, 

When you changed the sense resistor, was a calibration performed? When changing the sense resistor, you will need to perform a current calibration. 

Regards, 

Jonny. 

Calibration was performed.
A golden image file was created.

However, I am concerned that the FCC and QMAX are far apart.

FullChargeCapacity: 4924mAh
Cell 1 QMax: 8283mAh

I'm not sure if this will help, but the FCC rose sharply during charging and then dropped to zero when charging was nearing completion.

I would like to know if I missed any settings when changing 1m-ohm to 20m-ohm.

Hello, 

Can you please provide me with the golden image obtained after performing the current calibration for the 20 mohm sense resistor? Can you also please send over a log file with the described behavior? Finally, how was the chemID matched for the cells that you are using? 

Regards, 

Jonny. 

Hello,

>Can you please provide me with the golden image obtained after performing the current calibration for the 20 mohm sense resistor?
        I have attached it.20mOHM.gg.csv

>Can you also please send over a log file with the described behavior?
        This is the same email I attached the other day.7144.LogFile.zip

>Finally, how was the chemID matched for the cells that you are using?
        The sense resistor was 1mOhm, which was obtained using GPCCHEM.20240410-GPC.zip

Regards.

Hello, 

For the GPCCHEM tool, I see you have provided the data that you had submitted, but can you also provide the result from the tool? 

Regards, 

Jonny. 

Hello, 

This is the data returned.

Chemistry ID selection tool, rev=2.54		
		
Configuration used in present fit:		
ProcessingType = 2		
NumCellSeries = 1		
ElapsedTimeColumn=0		
VoltageColumn = 1		
CurrentColumn = 2		
TemperatureColumn = 3		
		
Best chemical ID : 2151	Best chemical ID max. deviation, % : 1.41	
		
		
		
Summary of all IDs with max. DOD deviation below 3%		
		
Chem ID	max DOD error, %	Max R deviation, ratio
2151	1.41	0.41
2127	1.43	0.59
2135	1.83	0.75
2442	1.93	0.28
242	1.95	0.28
257	1.96	0.46
2795	1.97	0.29
7276	2	0.48
2079	2.02	0.89
217	2.05	0.27
7410	2.27	0.51
5898	2.28	0.31
7498	2.3	0.72
2860	2.34	0.72
5977	2.35	0.48
5917	2.35	0.22
2102	2.41	0.58
2003	2.44	0.6
2082	2.45	0.93
2702	2.45	0.23
2713	2.51	0.2
2552	2.56	0.25
286	2.58	0.3
2833	2.59	0.38
2057	2.63	0.63
5979	2.63	0.47
7553	2.67	0.28
1954	2.7	0.48
2579	2.74	0.38
5975	2.77	0.42
2148	2.79	0.64
1321	2.81	0.77
1991	2.82	0.94
2491	2.84	0.65
2066	2.85	1.14
2877	2.86	0.4
2131	2.88	0.44
7543	2.89	0.2
7059	2.91	0.51
5890	2.93	0.36
1741	2.98	0.42
2863	2.98	0.4
		
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	14.95
3142	bq27421-G1D: 4.4V LiCoO2	19.1
128	bq27421-G1A: 4.2V LiCoO2	33.3
312	bq27421-G1B: 4.3V LiCoO2	38.11
Best generic ID 354		
Warning: Deviation for best generic ID is above recommended level for this device / family. Consider using another device, flash based gauge or RAM programming of custom ID.		
		
		
Device / Family #2		
Generic Chem ID	Device/ Voltage/ Chemistry	max DOD error, %
354	bq27621:  (ALT_CHEM2) 4.35V LiCoO2	14.95
1210	bq27621:  (ALT_CHEM1) 4.3V LiCoO2	15.18
1202	bq27621: (default) 4.2V LiCoO2	22.19
Best generic ID 354		
Warning: Deviation for best generic ID is above recommended level for this device / family. Consider using another device, flash based gauge or RAM programming of custom ID.		
		
		
Device / Family #3		
Generic Chem ID	Device/ Voltage/ Chemistry	max DOD error, %
3230	bq27426: (default) 4.35V LiCoO2	12.6
3142	bq27426: (ALT-CHEM2) 4.4V LiCoO2	19.1
1202	bq27426: (ALT_CHEM1) 4.2V LiCoO2	22.19
Best generic ID 3230		
Warning: Deviation for best generic ID is above recommended level for this device / family. Consider using another device, flash based gauge or RAM programming of custom ID.		
		
		

Regards, 

Hello,
The following results were obtained with GPCRA0.

Warning: Voltage under load 4167 mV is higher than OCV 4153mV. Please check correctness of your chem ID.

Do you know what the problem is?

1. Battery
2. GPCCHEM operation
3. GPCCHEM data
4. GPCRA0 operation
5. GPCRA0 data
6. Operation when creating Goldem Image File

Regards.

Can you please share the report that you received from the GPCRA0 tool? 

Regards, 

Jonny. 

こんにちは

Please tell me how to use GPCRA0. Should I start a new thread?

When should I use GPCRA0?

I thought about using the GPCRA0 tool with the GG file (golden image file) I created.

But the calculation engine reported an error.

The following errors were reported by the calculation engine:

Error:Ra table could not be extracted from GG file. Make sure that chem ID was freshly programmed and no learning took place.

Flags "ff55" or "ffff" should be present.

So I thought.

First, read ChemID. Then discharge, wait for 2 hours, charge, and wait for 2 hours. Create the gg file here.

Because the flag changes from ff55 before the discharge starts and the terminal voltage is reached.

Is this okay?

So I have a question.

When creating a golden image file, read ChemID.

Is that before writing the gg file obtained with the GPCRA0 tool?

Should I read ChemID after writing it?

よろしく。