BQ34110: How to implement learning cycle for BQ34110 with Li-ION battery?

Okay, Thanks for your quick reply.

I will try this and will give you updates.

I just want to know that do i need to set any design parameters in data memory before starting GPC cycle? And CEDV gauge require CHEM ID generation process?

Ok, i will do that! 

But what should be charging and discharging rate for GPC cycle for fuel gauge BQ34110. 

Thanks, 

Parth

I think you should use the typical system load when on battery. I will check to confirm.

Hi,

I could not find exact rate of charge and discharge from anywhere.

Can you help me to figure out that?

I am using BQStudio to implement GPC cycle in which there is a GPC cycle tab. That is what you are referring as GPCCEDV tool, Right?

Thanks,

Parth

I followed as you suggested but i could not find specific rate for charging and discharging the battery!

Thanks,

Parth

Hello Parth,

The rates depend on your application, they are different for all customers. The guide outlines that you should use the application specific high rate and low rate. We do not know what these would be for your application so you will have to set them to match your system.

Charging rate is specified by the battery manufacturer and is usually C/2 CC and C/10 for taper.

Sincerely,

Wyatt Keller

Ok, I got your point. 

And is it OK if i relax the battery more than 2 hours? 

Thanks,

Parth

Hello Parth,

Yes more than 2 hours is fine.

Sincerely,

Wyatt Keller

Hi,

I am using BQStudio and BQ34110 EVM to implement GPC cycle. I am connecting two 3.65V of battery in series having 1500mAH of capacity.

My GPC cycle is about to end as shown in below image but FCC and Remaining capacity has not been updated, so what should i do?

I am sharing log file and gg.csv file for your analysis. Please help me to find the solution.

Thanks,

Parth

I 6758.roomtemp_highrate.log

8712.1500 mAH Battery.pdf

Hello Parth,

You may not see any gauging related updates. The GPCCEDV log is independent of gauging functions. It only requires voltage, temperature and current. And this will be the input to the GPCCEDV tool.

Once you get the report , then you will program the parameters and after that start gauging to determine accuracy

Sorry, I don't get it.
What should i do now to get correct remaining battery capacity?

How to program the parameters and start gauging? What/How should i do to start gauging?

I am using two LiFePO4 batteries in series.

Thanks,

Parth

Ok, 

I found the document for the same in which there is mentioned that we need to create 6 files at different temperatures, but in order to do that i need to have temperature chamber to perform all those scenarios which i don't have it then what can be done? 

Also my project is going to get operated in 40-50/0-5 degC, it will be about 20-30 degC only so is it ok if i send same file generated at room temperature for all scenarios (low temp, room temp and high temp)? 

Thanks, 

Parth

Hello Parth,

You will require all 6 log files to be taken at the specified temperatures to make the gauge function accurately.

Is there any other way to take logs without temperature chamber? 

Thanks, 

Parth

Ok, Thank you!

I will try to implement it and will give you updates.

Thanks,

Parth

Hi,

I generated all logs files as it was suggested from manual and also i received GPC reports. But 3/6 files failed although following proper procedure.

I loaded these parameters of this GPC report in data memory of fuel gauge like EMF EDVC0 EDVC1 EDVR1 EDVR0 EDVT0 EDVTC and voltages of 0-100% but i am getting 0% in remaining capacity.

Here i am sending log files as well as GPC report for your reference, can you help me to figure out the solution to get accurate remaining capacity.

I don't understand what went wrong even though following all procedures properly. Can you point out specific reasons for failure from these files.

Also can you please give me specific procedure after loading all these parameters into data memory to get accurate remaining battery capacity.

Thanks,

Parth

GPCPackaged-report (4).zipBQ34110.zip 

Hello Parth, can you attach the gg.csv file?

7725.BQ34110.gg.csv

Please find attached gg.csv file for your analysis.

I am not getting accurate remaining capacity, which i am trying to figure out.

Also i could not find VOC75 VOC50 and VOC25 parameters in data memory, so where should i write these parameters?

I am using 2 LFP batteries with 3.6V in series connection.

Thanks,

Parth

7725.BQ34110.gg.csv

Please find attached gg.csv file for your analysis.

I am not getting accurate remaining capacity, which i am trying to figure out.

Also i could not find VOC75 VOC50 and VOC25 parameters in data memory, so where should i write these parameters?

I am using 2 LFP batteries with 3.6V in series connection.

Also i tried taking log again for hightemp lowrate, i don't understand the reason. Please help me to figure it out.

5428.GPCPackaged-report.zip3201.GPCPackaged.zipBQ34110_FuelGauge.gg.csv

Thanks,

Parth

Hello Parth,

The GPCCEDV report values are not in the gg.csv file. Please update

The report has a OCV11.txt file that has the OCV voltages that must program in CEDV profile.

I do not think this gauge uses VOC parameters.

Hi,

I generated new report today with new data and also i updated the report data into data memory of fuel gauge but still i am not getting accurate remaining capacity.
Please help me to find the solution, here i am attaching all log files for your reference.

I tried everything as it was suggested in reference manual and also tried generating the report by retaking logs again but although 3 logs are not getting passed out of 6 log files.

So please suggest if you find anything wrong with the procedure or if i need to follow any other procedure after updating the report data into data memory of fuel gauge to get accurate remaining capacity.

BQ34.gg.csv1777.GPCPackaged-report.zip8228.GPCPackaged.zip

This how i generated GPC package and as i have mentioned i am using 2 LFP 3.6V batteries in series connection. And for my application full charge voltage = 7000mV and full discharge voltage = 5200mV.

Thanks,

Parth

Hello Parth,

Send a reset command after all parameters have been set. Ideally the battery should have been at rest(no charge / discharge for at least 2 hours) when the reset command is sent.

Can you also elaborate on how you reached the conclusion about "accurate remaining capacity"

I have generated new report today and then updated the report parameters into data memory of fuel gauge and also waited for 2 hours for relaxing, although i am getting 0% remaining capacity.

I am getting only 0% remaining capacity even after doing everything and that is how i came to conclusion that i am not getting accurate remaining capacity. If i am not getting passed all 6 files although after updating all the report parameters into data memory i should get some remaining capacity, it should not be 0%, Right?

I am sharing all latest files for your analysis.

5758.GPCPackaged-report.zip8117.GPCPackaged.zipbq3411.gg.csv

Also as i have mentioned i am not getting passed 3 files out of 6 in the report even after following all procedure properly suggested from reference manual. I don't understand the reason. What could be the possible reasons of failure. I tried 3 times although i am not able to pass all files.

Please let me know if there is any other procedure/process which i need to follow after generating the report and updating all these parameters into data memory in order to get proper/accurate remaining capacity?

Thanks,

Parth

Please help me to find the solution. 

I have shared all required files for your analysis. 

Thanks,

Parth

Hello Parth,

I would first get good match from GPC. The data that is submitted has an issue if there is no match.

I tried to analyze the low temp low rate file that has the highest deviation. You can see that there is no "knee".  Comparison graphs are below. Low temp vs room temp. Since battery impedance increases at low temperature, this is is not normal.

Low temp

-----

Room temp

That is what i don't understand and need your help with!

I have taken low temp log files at suggested temperature (0 - 5 degC), then why it's getting rejected in the report?

www.ti.com/.../sluub45b.pdf

Please help me to understand it, what i have done wrong during the procedure.

Thanks,

Parth

Hi,

Thank you for replying at this time.

I tried as you suggested although 2 files could not pass in GPC report out of 6.

I am sharing all files for your analysis.

Thanks,

ParthGPCPackaged_Report.zip6445.GPCPackaged.zip

Ok, I will try it and give you updates. 

Thanks, 

Parth

Hi,

We tried different combinations in config files and we generated new report in which only 1 file out of 6 was not passed.
We updated this report parameters and performed accuracy testing to check whether remaining capacity is decreasing as it should or not.

But in this test result were not perfect.

Can you please look into our report and testing file to analyze what went wrong?

0602.GPCReport.zipBattery_accuracy_test.xlsx

Thanks,

Parth

Hello Parth,

There is no other information in the accuracy file besides voltage and SOC, this is not enough information to assist in debugging the issue. can you provide a BQStudio log of the test?

Sincerely,

Wyatt Keller

Hello Wyatt,

I was communicating with the sales representative of TI and that, he refers to continue the dialogue on this and obtain your email address so that we can connect via Teams to talk live. Can you provide your email address so that we can connect live to resolve this issue? Thank you.

BQ34110_new.gg.csv793 cell2-report.zip

Please find attached all logs for your analysis.
I am getting 732mAH only instead of 1500mAH and also battery percentage is getting to 0% at 6.3V only as shown in voltage vs soc sheet above.

Please help me figure out how this issue, how to achieve proper accuracy for remaining battery percentage.

I have followed all procedures exactly as suggested in TI reference manual although some of files are not getting passed from GPC tool, i don't understand the reason.

Thanks,

Parth

793 cell1-report.zip

Hi,

Need your expertise to solve my current issue.

I used this report for accuracy testing.

For my application i am using two 3.65V batteries connected in series.

When i am doing testing with same voltage in both batteries, i am getting accurate RSOC with respect to voltage.

But when i tested with different voltage of both batteries (battery 1 - 3.3V, battery2 - 3.6V), i am not getting proper RSOC then what should i do?

RSOC got dropped from 88% to directly 7%.

Thanks,

Parth

But I have implemented GPC Cycle and according to it i have set parameters in data memory of fuel gauge.

In this case do i need to perform chg-dischg cycle every time when i connect the cells to gauge?

Thanks,

Parth

Hi,

When we put our product in production line, there is no possibility that they are going to keep same voltage in both cells. Voltage may not be same in each product. So at that how it is possible to perform this cycle.

Because as per my understanding once we generate golden image, we flash it in all products and after then fuel gauge starts giving us accurate readings, but as per your saying we need to perform chg-dischg cycle every time when we connect different voltage cells but how it possible to do this once we start mass production?

Thanks,

Parth

Can you please explain me how to do cell balancing?

Thanks,

Parth

So fuel gauge with chem ID type are better to use, Right?

It provides better accuracy than this like BQ34110. I think, It also has inbuilt cell balancing capacity.

Thanks,

Parth