BQ34Z100-G1: Design energy learning cycle importance

Matej Pinter

Part Number: BQ34Z100-G1
Other Parts Discussed in Thread: BQ34Z100

Tool/software:

Hello,

1. I successfully finished learning cycle for new battery pack. After generating golden image, I discovered that the design energy I entered before executing the learning cycle was incorrect. Do I need to repeat the learning cycle with correct design energy parameter, or is that not relevant during learning cycle? Can I change it now and just generate the golden image again without repeating the learning cycle? I used Load select = 2, Load mode = 0.

2. Also to clearify could you please confirm my calculations are correct. I have a pack of 13S3P. Single cell data:

Capacity = 5650 mAh

Nominal voltage = 3.59 V

So the data I need to enter in bq data memory is:

Design capacity = 5650 mAh * 3 (cells parallel) = 16950 mAh

Design energy = 16950 mAh * 3.59 V = 60850.5 mWh = 6085.05 cWh ----> Energy scale = 1 ------> Design energy = 6085 cWh
With the bq34z100 FW Version: 2.02.31 the unit for design energy is cWh (as I see in bq studio), so I enter 6085. Is that correct?

Best regards, Matej

6 months ago

+1 Alan Frias 6 months ago

TI__Mastermind 26395 points

Hello Matej,

1.) I would recommend redoing the learning cycle in order to minimized errors on the final product regardless of the load select and emphasize on following the proper length on the relaxation period.

2.) The math you listed is right in finding the design capacity and the design energy

Thank you,
Alan

0 Matej Pinter 6 months ago in reply to Alan Frias

Prodigy 60 points

Thank you for answer,

What about design voltage? Is that nominal voltage of single cell * number of cells in series ? Or only nominal voltage for single cell?

In the document "Achieving The Successful Learning Cycle", it is written that for design voltage I should multiply with the number of cells in series, but it is weird to me that design energy is not multiplied with number of cells in series and design voltage is.

0 Alan Frias 6 months ago in reply to Matej Pinter

TI__Mastermind 26395 points

Hello Matej,

Design voltage is the nominal voltage of one cell times the amount of cells in series

Thank you,
Alan

0 Matej Pinter 6 months ago in reply to Alan Frias

Prodigy 60 points

Thank you, so for my project my design voltage is 3590 * 13 = 46670 mV. This is out of bounds for this parameter, so I should change volt scale? Does volt scale have effect for any other voltages? Do I need to adjust all other voltage parameters if I change volt scale? I did not find this info in any of the documents.

Best regards, Matej

0 Alan Frias 6 months ago in reply to Matej Pinter

TI__Mastermind 26395 points

Hello Matej,

Yes you would need to scale your voltage to be able to use that capacity with this battery gauge. Please review section "3.8 Scaled Mode" to better understand the steps needed to do for this change.

3.8 Scaled Mode:
https://www.ti.com/lit/ug/sluubw5a/sluubw5a.pdf?ts=1741378169938&ref_url=https%253A%252F%252Fwww.ti.com%252Fproduct%252FBQ34Z100-G1

Thank you,
Alan

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BQ34Z100-G1: Design energy learning cycle importance