BQ34Z100EVM: Unable to complete learning cycle for NiMH battery pack.

Olav Zeeuw

Part Number: BQ34Z100EVM
Other Parts Discussed in Thread: BQ34Z100, BQSTUDIO

After multiple attempts to complete a learning cycle for an NiMH battery pack, I have been unable to get the learning status byte to update.
The battery was determined by the chemistry ID selection tool to have a closest matching ID of 6114 with an uncertainty of 5.2%.
The pack consists of 4 series cells of 1.2V with a capacity of 2500mAh (NW50AA2500J).

The following settings have been set according to document SLUA903 before enabling the impedance track algorithm:
taper current: 200
design capacity: 2500
dsg current threshold: 60
chg current threshold: 75
quit current: 40
term voltage: 1100
pack config: 0x49d9

After discharging the battery to empty and charging back up to full, the update status byte never updates to 0x05.

I have included logs of the discharge and charge cycle and my srec file.

Thank you,

Olav

6330.bq34z100.zip

over 5 years ago

0 Wyatt Keller over 5 years ago

TI__Guru** 105760 points

Hello Olav,

Have you followed the document linked in this thread: https://e2e.ti.com/support/power-management/f/196/t/825535

It outlines the steps needed for NiMH batteries to complete the learning cycle.

Sincerely,

Wyatt Keller

0 Olav Zeeuw over 5 years ago in reply to Wyatt Keller

Prodigy 40 points

Hello Wyatt,

Thank you for your response, I have attempted another learning cycle with the additional settings from the linked document, however, the update status will still not advance to 0x05.

Could there be something else I'm doing wrong? I have attached my latest .srec file.

Thanks,

Olav

5187.OutputFiles.zip

0 Andy Liu (BMS) over 5 years ago in reply to Olav Zeeuw

TI__Guru 52115 points

Do you have a bqStudio log for your latest learning cycle? If so, please share it with us.

If you don't, I would suggest you rerun the leaning cycle and provide a bqStudo log file.

Andy

0 Olav Zeeuw over 5 years ago in reply to Andy Liu (BMS)

Prodigy 40 points

Here are my latest logs. I had to rerun the learning cycle to obtain these.

Olav

5635.log.zip

0 Wyatt Keller over 5 years ago in reply to Olav Zeeuw

TI__Guru** 105760 points

Hello Olav,

I will review the log files tomorrow and give some feedback then.

Can you also provide the .gg file of the settings? We have to have the EVM in order to load .srec files and most of us are not in the lab currently.

Sincerely,

Wyatt Keller

0 Olav Zeeuw over 5 years ago in reply to Wyatt Keller

Prodigy 40 points

Hello Wyatt,

Here are the settings I used.

Kind regards,

Olav

7840.settings.gg.csv

0 Wyatt Keller over 5 years ago in reply to Olav Zeeuw

TI__Guru** 105760 points

Hello Olav,

Sorry for the late response, I have been reviewing your logs. Make sure you still get a 90% change in DOD during the learning cycles, this may be preventing your update status from incrementing from doing a Qmax update.

Sincerely,

Wyatt Keller

Power management

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BQ34Z100EVM: Unable to complete learning cycle for NiMH battery pack.