BQ34Z100-G1: Learned Status doesn't update after charge cycle

Following the log the learning cycle (end of relax) charge -> Relax

21082023_NiMH.log

Regards

Mahfoud

Mahfoud Drouaz

    For NiMH or LeadAcid Battery, Qmax update does not occur after charge, you should be able to see Update status advances to 5 after a full discharge cycle and required relaxation time before and after the discharge.

Hi Steven, 

I did a full discharge cycle and relaxation ( > 16h relaxation), I still get learned status = 4.

I attached full learn cycle data log if that can help to understand what happen.

5773.21082023_NiMH.log

Can I restart a new learn cycle with the same chem ID ?

I get form the GPC a Chem ID 6107 that correspond to an NiMH (500mAh) and my pack battery is has 2600mAh capacity.

Is htere any relation between the chemistry and the design capacity ?

Regards

Hi Steven, 

About the chem ID value, I get 3 reports from the GPC, it seems that the 6117 is the best matching chemID instead of used 6107.

https://e2e.ti.com/support/power-management-group/power-management/f/power-management-forum/1260251/bq34z100-g1-chemical-id-selection

I did a new learn cycle last night without success, with downgrade firmeware version from the bq34z100_v2_02_build_30.srec to the bq34z100_G1_v0_16_build_17.srec

bq34z100_v2_02_build_30.zip 4760.bq34z100_G1_v0_16_build_17.zip

For the next step, I will use the chem ID 6117 and restart a new learn cycle. In my log file, I can see that the current discharge range of my bench test is between [350 to 400mA], is it important to have a constant current for the learn cycle ? 

Regards

Mahfoud

Hi Steven, 

My last learn cycle with the chem ID 6117 doesn't succed. I attached the log data of the cycle.

About the current discharge, the bq34z100-g1 technical Reference specify discharge to empty @ > C/10, is it right ?

What should be the value of the DOD0 in my case ?

1513.roomtemp_rel_dis_rel.xlsx dataflash.gg.xlsx

Hi Steven, 

Since I reload a new src on the gauge to test new configuration. I can restart a learn cycle and then send you the FW.

How can I extract the FW from the device ? On the bqstudio I have only choice to program or Execute FW.

Hi Steven

Please find attached the extracted FW with the log and the gg.csv files.

NIMH_2600mAh.zip

Regards

Thanks Steven, 

I am testing that.

When I calculated The Flash Update OK Cell Volt parameter I found 5939mV which is beyond the maximum value defined for the parameter.

I have a Voltage Divider 16580mV and 7cells. So how I can select the right value for this parameter ?

- Please also be noted that the bits[NI_DT] and [NI_DV] shall be set appropriately to match with the actual charge termination method adopted in your case.

Do you mean only used method should activated ? which is in my case the [NI_DV]

- The FC Set shall be set to -1 for 100% rsoc to be synchronized with charge termination detection

Ok, I changed the FC set to -1

What should be the value of NiMH Cell Neg Delta Qual Volt ? default = 4200mVolt

Regards

Hi Steven, 

With the new configuration, I get learned status = 5 at end of full discharge and relax mode.

At the end of the full charging mode, I didn't get FC = 1, I stoped to charging the battery despite this because the temperature of the pack battery exceed 50°C and I seen the Cell Negative Delta Volt occurs.

What I shoud be do at this step ? restart the learn cycle with the same configuration ?

20230829_NiMH_2600mAh.zip

Hi Steven,

Thanks, I will change that and restart a new cycle.

What should be the value of the taper current ? default 100mAmp

Hi Steven, 

I get learned status = 6 with attached gg.csv configuration. The flag FC still doesn't detect the full charge and the full charge capacity is very low 453mAh !

I also changed the Current Taper to 800mA as suggested in the SLUA664 charge termination chapiter.

Is it necessary to change the FC set form -1 to 100% now the learn cycle finished?

Regards

20230831_NiMH_2600mAh.zip

Hi Steven, 

Attached the log file of this learning. 

20230831_NiMH.log

I get new issue after exporting the Golden Image from the bq34z100g1 which completed the learn cycle.

I load the .srec file on two new borads with the same issue:

• After a successful operation, I lost communication with the chip
• I tried to read registers of the chip. No response. I also tried to reprogram the device, still no response. Clicking Execute FW doesn't help.

Any idea to help ? I attached the generated FW

3465.20230831_NiMH_2600mAh.zip

Regards

Mahfoud Drouaz

   You can check the waveform on the TS pin, see if there is pulse at regular interval can be monitored, if not, then the device could probably damaged somehow.

   I will check the log file and give you reply later on

Thanks Steven

The TS pin doesn't leave. So I changed the gauge component and regenerated new FW files, since I only use the df.fs file.

I think that first generated FW files are corrupted.

Steven

 I found the -delta V at the end of charge is 10913 - 10850 = 63, but the NiMH Cell Negative Delta Volt is 10mV, still less than this threshold

It's 63mV for 7 cells, so 9mV per cell. I will try to reduce it.

One most important thing I should correct myself is that the NiMH Cell Neg Delta Qual Volt is for single cell voltage, so 4200mV here is INCORRECT, it should be configured with maximum single cell voltage during charging. Please check the spec of the battery to find appropriate value for this parameter.

In my last test I reduced this parameter to 1500mV per cell. So 10500mV for the pack battery. 

Mahfoud Drouaz

    It is better to consult these 2 parameters with your cell supplier, I found in the latest upload gg file the NiMH Cell Neg Delta Qual Volt is still 4200mV, do you mean that you would change these 2 parameters and redo the test to see the improvement?

Steven, 

I mean that I did new learn cycle with another board with modifyed following parameters:

• NiMH Cell Neg Delta Qual Volt = 1500mV per cell, I choose this value based on the following explanation

• CC Thershold = 900mAmpHr
• Load Select = 3

the FC bit still not detected.

Attached the gg, log andc FW files.

20230904_NiMH_2600mAh_Board2.zip

I get new issue with the df.fs file when I flash the gauge, the I2C break when I load the df.fs file.

How I can check if generated FW are not  corrupted ? In 2 days I changed 5 chips due to this problem !

Regards