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BQ34Z100-G1: How to calibrate the gauge

Part Number: BQ34Z100-G1
Other Parts Discussed in Thread: BQ34Z100EVM, EV2400, GPCCHEM, BQSTUDIO, , BQ34Z100

Hello,

 

First here my settings:

- BQ34Z100EVM

- EV2400, version 18

- Lead Acid battery, 12V 7Ah

- BQ Studio, version 1.3.86

 

I have already done these things:

- Current and voltage calibration

- Find the Chemical ID using the GPCCHEM tool

 

But now I have two problems to end the calibration:

- I want to change the value of “Design Capacity”, “Terminate voltage” and other things but bqStudio tells me “a read of data written failed comparison”. It don’t change the value. I have tried many things: UNSEAL FULL ACCESS, ENTER_CAL, CAL_ENABLE. I have also tried to use the BQ studio version 1.3.54.1 but I get the same message. I can I fix this?

- How should I do the learning cycle? Is only one cycle enough? I there a special way to discharge the battery? Do I have to send specific commands to the BQ34Z100-G1 or will it do the calibration automatically?

 

Thank you in advance and sorry for my bad English,

Guénolé

  • Hello all,
    If nobody has the solution, do someone knows how can I reprogram the BQ34Z100 as it was new ? Kind of "out of factory" settings. Maybe using the bq.fs and .srec files (but I don't have them).
    Thank you,
    Guénolé
  • Hi Guénolé,

    Please use the 1.3.86 version for bqStudio and not the 1.3.54 version.

    To reset the gauge, download the firmware here (its an installer for the SREC): www.ti.com/.../sluc580

    With the fresh firmware, change flash update OK voltage to '0' before modifying the series value.

    With respect to learning cycle:

    Follow the learning cycle guide linked here, but with the modification below: www.ti.com/.../slua903.pdf

    For lead acid, the learning cycle will need to be performed as two charge+rest+discharge+rest cycles because the gauge will learn on the discharges for lead acid (whereas in the guide above for Li-ion the gauge will learn on the charge and then again on discharge). Also, ensure the device fully rests - it may take more than two hours after charge.

    If you have any other questions, please let me know.

    Sincerely,
    Bryan Kahler
  • Hi Bryan and thank you for your answer,

    I have two more questions:

    1) I have successfully reset the gauge but now I can’t do the Voltage calibration. The resistor divider network is set to the proper position to calibrate 12V (15V position). But I get this message: “Calibration – Cell Voltage correction is beyond allowed range.”

    2) I have set these parameters:
    ∙ Taper current = 200 mA
    ∙ DSG current Threshold = 80 mA
    ∙ CHG current Threshold = 80 mA
    ∙ Quit Current = 40 mA
    ∙ Cell Term Voltage = 11000/6 = 18300 mV
    ∙ Number of series cell = 6
    ∙ Design Capacity = 6500 mAh
    Do I need to set other parameters? I see that other user sometimes set “Design Energy” or “QmaxCell” but I am not sure to understand what these parameters mean.

    Regards,
    Guénolé
  • Hi Guénolé,

    Set Number of series cell = 1 and attempt voltage calibration again.

    If the error persists, remove all versions of bqStudio from your system and install fresh, ensuring no old files remain. Then, reattempt voltage calibration. If the error still persists, please let me know.

    Sincerely,
    Bryan Kahler
  • Hi Bryan,

    It did not work using Number of series cell = 1, so I used another computer with only bq studio 1.3.86 but the computer was not able to detect the gauge. I says : "Autodetected Device : None"

    So, I replug on the old computer but I get the same message. I suspect that the component may be dead, but I really don’t know why…

    The LEDS seem to work, 0, 1, 3, 4, 5, 7, 8 and 9 are ON. Sometimes the LED 3 is also ON.

     

    I have measured all potentials around the BQ34Z100:

    1)      0.53 V

    2)      0.53 V

    3)      0.53 V

    4)      0 V

    5)      3.1 V

    6)      3.1 V

    7)      0 V

    8)      0 V

    9)      0 V

    10)   0 V

    11)   0 V

    12)   0.1 V

    13)   2.1 V

    14)   2.1 V

    If you think these the values are good, I can change the BQ34Z100, I have another one in stock and I am able to solder it.

     

    Thank you,

    Guénolé

  • Hi Guénolé,

    Please try to communicate with the device at address 0x16 and 0xAA. If both are NACK'ed and there is no pulse measurable on the TS pin, please replace with the other device.

    Sincerely,
    Bryan Kahler
  • Hi Bryan and thank you again for your help!

    I replaced the device and it works. But I am still not able to calibrate the voltage. I think that it may be because VOLCEL=0 whereas it should be at 1. But I don't know how to change it.

    Regards,
    Guénolé
  • Hi Guénolé,

    If using the internal divider, please set VOLSEL = 0 and set Voltage Divider = 5000.  Voltage calibration may not be required for internal use.

    When using the external divider, please selt VOLSEL = 1 and set Voltage Divider = VoltageDividerRatio*1000  (e.g., an 11:1 divider would be 11000).

    To set VOLSEL = 1, Go to Data Memory > Configuration > Registers and click on Pack Configuration.  The registers window will pop up.  Click on VOLSEL.  With default settings, red indicates 1 and green indicates 0, as shown in the image below:

    If issues persist, please let me know.

    Sincerely,

    Bryan Kahler

  • Hi Bryan,

    I have one last question before starting the learning cycle. The datasheet says, if I discharge my battery at a constant C/20 rate, the battery is empty when the voltage drops to 10.5V. But then, when the battery relaxes, the voltage raises to 11.4V. So, witch value should I use for “Cell terminal voltage”? 10.5V/6 or 11.4V/6 ?

    Regards,
    Guénolé
  • I forgot, I have another thing to ask (please consider this post, and the one just above),

    I am curious if the parameter labeled "Device Chemistry" is used in the firmware of the device? If so, what are the allowable values?
    Can I change it to PbA for exemple?

    Thank you,
    Guénolé
  • Hi Guénolé,

    The terminate voltage is the minimum allowable voltage as specified in the datasheet. When the cell relaxes after a discharge, the measured voltage will increase.

    With respect to the Device Chemistry parameter, setting the value to PBA is permissible.

    Sincerely,
    Bryan Kahler
  • Hi Bryan,

    I have tried the learning cycles, but it has not worked. I have multiples questions concerning the www.ti.com/.../sluc580 you gave me:
    1. In “Discharge the battery to empty”, I have done IT_ENABLE and RESET (in commands) but did not changed automatically to 04. I had to set manually. Is it normal?
    2. In “Relax for at least 5 hours”, where is the GaugingStatus[REST] flag? I can’t find it.
    3. In “Relax for at least 2 hours”, where is the [QMax] flag?
    4. In “Relax for at least 2 hours”, the Update Status did not change automatically to 05. Is it normal ?
    5. In “Relax for at least 2 hours”, does Qmax = Qmax cell 0? If it is the case, it didn’t change.

    Thank you,
    Guénolé
  • Hi Guénolé

    As long as IT_ENABLE has not been used previously, IT_ENABLE should set it to 0x04.

    For (2) and (3) these flags were specific to the device the learning cycle guide was written for. For (4), if Update status does not increase from 0x04 to 0x05, qmax was not updated, which makes sense for (5).

    Please send your SREC, gg.csv file and log of the failed learning cycle for analysis.

    Sincerely,
    Bryan Kahler
  • Hi Bryan,

    Please find attached, the requested files.

    Thank you,

    Guénolé

    6560.BQ34Z100.zip

    LEARNING_CYCLES.log

  • Hi Guénolé,

    Thank you for the files - will review and respond by EOD Wednesday

    Sincerely,
    Bryan Kahler
  • Hi Guénolé,

    Just had an internal update to the simulator. Re-running the results. Will update tomorrow.

    Sincerely,
    Bryan Kahler
  • Hi Guénolé,

    I apologize for the delay - still waiting on a dll for the simulator. Expect to have it tomorrow. Will provide another update tomorrow.

    Sincerely,
    Bryan Kahler

  • Hi Hi Guénolé,

    Good news - have the new dll. Simulation is running and I'll be able to report the results on Monday.

    Sincerely,
    Bryan Kahler
  • Hi Guénolé,

    Not getting the expected results with the simulator. Will update tomorrow (Tuesday).

    Sincerely,
    Bryan Kahler
  • Hi Guénolé,

    Log looks good.  This is a lead acid cell so the charge+rest+discharge+rest must be carried out first for update status to change from 0x04 to 0x05 and a second time for update status to change from 0x05 to 0x06.  Please perform the charge+rest+discharge+rest again to allow the gauge to update to 0x06 from 0x05.

    As shown in the image below, the gauge has updated from 0x04 to 0x05 after the first charge+rest+discharge+rest cycle:

    Sincerely,

    Bryan Kahler