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BG34Z100-G1 with Lead acid battery

MickaelWhite
Prodigy 240 points
Other Parts Discussed in Thread: BQSTUDIO, BQ34Z100EVM, BQ34Z100-G1

Hi,

I want to use BG34Z100-G1 with a lead acid battery YUASA NP7-12L 12V, 7Ah. I use bqStudio and I read voltage, current and temperature but remaining capacity and state of charge % are not updated (value 0) and max error  is always 100%.

What is missing ?

Thanks

  • 0
    TI__Guru 73830 points

    I would check to make sure that the Term V is set properly. Capacity reporting will be 0, if it is still set for a Li-Ion pack.

  • 0 in reply to ThomasCosby
    Prodigy 240 points
    What does it mean "Term V" ? How can I configure it with bqStudio ? Thanks
  • 0 in reply to MickaelWhite
    TI__Guru 73830 points

    That is the Cell Terminate Voltage and it is located in the Gas Gauging section of the Data Memory. It should be set to the cell voltage where you want SOC = 0%.

  • 0 in reply to MickaelWhite
    Prodigy 240 points
    Sorry, I just find it in Gas Gauging parameters in Data Memory. The designation is "Cell Term V Delta". I try the recommended value "100" for Lead Acid.
  • 0 in reply to MickaelWhite
    TI__Guru 73830 points
    We usually see a terminate voltage in the 1000mV to 1100mV range for PbA cells.
  • 0 in reply to MickaelWhite
    Prodigy 240 points
    Ok and I find the other parameters "Cell Terminate Voltage", "Default Load Select" and "Min % Passed Chg for 1st Qmax". A very important question, how many cells for a Lead Acid Battery ? I don't find this information in the data-sheet of the YUASA Lead Acid Battery ?
  • 0 in reply to MickaelWhite
    TI__Guru 73830 points
    If it is a 12V battery, then it is 6S. Most PbA batteries are 6S.
  • 0 in reply to ThomasCosby
    Prodigy 240 points
    Dear Thomas,

    I manage bqStudio with the evaluation kit BQ34Z100EVM and the 12V 7Ah lead acid battery.
    I have carefully configured jumpers for voltage greater than 5V.
    I have carefully calibrated and I watch correct current, voltage and temperature.

    I have modified the next parameters in the data flash in the profile issued from the 0x0805 Lead Acid profile :
    - Design Capacity : 7000 (mAh)
    - Cell Terminate Voltage : 1000mV
    - Number of series cell register : 6
    - Pack configuration register : 0x09d9
    - ...
    For the parameter Designe Energy, I don't know which value to use. Energy Density (Wh.L.20hr : 91) and Specific Energy (Wh.kg.20hr : 32) are the only informations supplied with YUASA Industrial Lead Acid battery.
    For the Voltage Divider, can you confirm that using bq34z100EVM, the design and the configuration of the voltage divider are made by the configuration of the jumpers on the evaluation board ?

    At the end, I get no value for State Of Charge (0), Remaining Capacity (0), Full Charge Capacity (0), Max Error (100). I should expect to get values which were not accurate but not 0 !

    So I wonder if I have hard problem on my evaluation kit, or if I forgot hard or soft configuration action.

    Thank you for your help.
  • 0 in reply to ThomasCosby
    Prodigy 240 points
    Dear Thomas,

    I forgot a question about the Qmax Cell 0 parameter. What does the followed explanation mean (extracted from an application note, advising for the Qmax Cell 0 initialization) : "Start with C-rate value of your battery" ? The Qmax Cell 0 value must take the value of 7Ah or the value of 7000mAh/6cells = 1166mAh for cell 0 ?
  • 0 in reply to MickaelWhite
    TI__Guru 73830 points
    Did you calibrate this voltage? If not, that could cause the capacity values to be zero. You will set Qmax Cell 0 to 7000mAh and the DesignEnergy will be 7000 x the cell voltage (2V) = 14000mWh.
  • 0 in reply to ThomasCosby
    Expert 1112 points

    Hi all,
     
    I too am having some confusion regarding the capacity values for setting up a 12V, 6 cell, lead acid battery.
    In the above comment you said Qmax Cell 0 should be 7000 mAh which I understood to be the battery capacity, not the cell capacity.
    So, should the parameter Qmax Cell 0 be 7000 or 7000 / 6 ?
    Should be Design Energy value be based on cell voltage and cell capacity, or should it be based on pack voltage and pack capacity?
    Any help would be greatly appreciated!

    Regards,
    -Tim W.

  • 0 in reply to BatMan
    TI__Guru 73830 points
    Capacity is always set at the cell level, so the battery capacity and cell capacity are the same. If a cell has 7000mAh capacity, then a 1S pack is 7000mAh and a 6s pack is 7000mAh. Energy is normally defined at a pack level, so the Design Energy would normally be the Design Capacity x Pack Voltage. The bq34z100-G1 sets all parameters at a cell level, so the Design Energy is the Design Capacity x the cell voltage. Qmax is 7000 in your case.
  • 0 in reply to ThomasCosby
    Expert 1112 points
    Ahh..
    That explains my confusion!
    Thank you for your quick reply.
  • 0 in reply to ThomasCosby
    Prodigy 240 points

    Hi,

    Thanks to Tim and Thomas for their discussion. It clarifies several points.

    I need a  tutorial to run a learning cycle on the pack to calibrate Qmax and the Ra-table. 

    Thank you to give me a link.

  • 0 in reply to MickaelWhite
    TI__Guru 73830 points

    Mickael,

    The optimization cycle process is shown in several documents, but it may vary slightly between device families. Here is a process that should work for your PbA cells.

    1. Configure the dataflash with appropriate parameters suitable for your application; configure pack's chemistry and perform calibration.
    2. Activate impedance track.
    3. Charge the pack to charge termination.
    4. Allow the pack to rest until the OCVTAKEN flag sets.
    5. Discharge the pack at a C/8 rate to the Termination Voltage.
    6. Allow the pack to rest until the OCVTAKEN flag sets. Qmax should update and Update Status should increment to 05.
    7. Fully charge the pack to charge termination.
    8. Allow the pack to rest until the OCVTAKEN flag sets.
    9. Discharge the pack at a C/8 rate to the Termination Voltage.
    10. Allow the pack to rest until the OCVTAKEN flag sets. The Ra table should update and Update Status should increment to 06.

    Tom

  • 0 in reply to ThomasCosby
    Prodigy 240 points
    Thomas,

    Thank you for the tutorial

    I am not still sure to initialise the good values in the data flash for the following parameters :

    SOHLoadI : 400mA ; if this parameter is the current rate max in discharge , it would be 875mA (C/8) ?
    CCthreshold : 900mAmpHr what does it mean ?
  • 0 in reply to MickaelWhite
    TI__Guru 73830 points
    The SOHLoadI is the current that the gauge uses for the SOH simulation. It also forces the temperature to 25 degC for the SOH simulation to have a known set of current and temperature values when calculating SOH. We typically set the SOHLoadI to -400mA to be a typical discharge rate. It should not be set to your maximum discharge rate. They goal to is for the SOH value to reflect changes in Qmax and the Ra table as the pack degrades.

    The CCThreshold should be set to the amount of Passed Charge that you want represent a full discharge cycle. The CycyleCount will increment after the Passed Charge during discharge reaches the CCThreshold value. It can be within one discharge cycle or over multiple cycles.
  • 0 in reply to ThomasCosby
    Expert 1525 points

    Thomas,

    You say that DesignEnergy will be 7000 x the cell voltage (2V) = 14000mWh. But on SLUSBZ5A (bs34z100-G1 Datasheet) I find on the page 49, 9.2.2.1.1 STEP 1, this one:

    •Design Capacity: Enter the value in mAh for the battery, even from the “design energy” point of view.
    •Design Energy: Enter the value in mWh.

    So I understand that Design Energy = Design Capacity x the BATTERY voltage = 7000 x 12 = 84000 mWh (Out of range)

    Because this value is out of range,  I find in the document "Design Energy Scale" parameters with "Saled" mode, so:

    Design Energy = (Design Capacity x the BATTERY voltage ) / Design Energy Scale = (7000 x 12) / 3  = 28000 mWh

    My question is : Do you have a "How to" for writing correct value of parameters, because we have some different between Typical applications (SLUSBZ5A) and you?

    Loïc

  • 0 in reply to LOIC REBOUSSIN
    TI__Guru 73830 points
    Loic,
    I mentioned in my earlier posting that all parameters on the bq34z100-G1 are handled at a 1S level, so you will use the cell voltage for the Design Energy calculation. You are correct that this is different than the setup used on other gauges. One other note is the the Design Energy does not matter unless you have the Load Mode set to 1 for constant power mode.
    Tom
  • 0 in reply to ThomasCosby
    Expert 1525 points
    Thank you for your reply,

    Loïc
  • 0 in reply to ThomasCosby
    Prodigy 240 points

    Hi Thomas, 

    I manage successfully the Qmax and Ra-table calibration. State of charge and state of health were updated to 100% and Max Error to 1%. However Remaining Capacity and Full Charge Capacity.get the value 339mAh. I don't understand these values because the design capacity is 7000mAh. 

    Thank you for your reply.

  • 0 in reply to MickaelWhite
    TI__Guru 73830 points

    Mickael

    Can you export an srec file from the pack and attach it to this forum? The log file from the optimization cycle will also be helpful in analyzing this problem.

    Tom

  • 0 in reply to ThomasCosby
    Prodigy 240 points

    Lead Acid Cycle.7z

    Lead Acid data memory.txt 
    * Texas Instruments Data Flash File
* File created Thu Oct 08 16:04:39 2015
*
* Device Number 100
* Firmware Version 0.16
* Build Number not available
* Order Number not available
*
* bqz Device Number 100
* bqz Firmware Version 0.16
* bqz Build Number 17
*
* Field Order: Class name, Subclass name, Parameter name, Parameter Value, Units
Configuration,Safety,OT Chg,50.0,1degC
Configuration,Safety,OT Chg Time,2,Seconds
Configuration,Safety,OT Chg Recovery,45.0,1degC
Configuration,Safety,OT Dsg,60.0,1degC
Configuration,Safety,OT Dsg Time,2,Seconds
Configuration,Safety,OT Dsg Recovery,55.0,1degC
Configuration,Charge Inhibit Cfg,Chg Inhibit Temp Low,-10.0,1degC
Configuration,Charge Inhibit Cfg,Chg Inhibit Temp High,45.0,1degC
Configuration,Charge Inhibit Cfg,Temp Hys,5.0,1degC
Configuration,Charge,Suspend Low Temp,-5.0,1degC
Configuration,Charge,Suspend High Temp,55.0,1degC
Configuration,Charge,Pb EFF Efficiency,100,%
Configuration,Charge,Pb Temp Comp,24.960,%
Configuration,Charge,Pb Drop Off Percent,96,%
Configuration,Charge,Pb Reduction Rate,10.000,%
Configuration,Charge Termination,Taper Current,100,mAmp
Configuration,Charge Termination,Min Taper Capacity,25,mAmpHr
Configuration,Charge Termination,Cell Taper Voltage,100,mVolt
Configuration,Charge Termination,Current Taper Window,40,Seconds
Configuration,Charge Termination,TCA Set %,99,Percent
Configuration,Charge Termination,TCA Clear %,95,Percent
Configuration,Charge Termination,FC Set %,100,Percent
Configuration,Charge Termination,FC Clear %,98,Percent
Configuration,Charge Termination,DODatEOC Delta T,10.0,1degC
Configuration,Charge Termination,NiMH Delta Temp,3.0,1degC
Configuration,Charge Termination,NiMH Delta Temp Time,180,Seconds
Configuration,Charge Termination,NiMH Hold Off  Time,100,Seconds
Configuration,Charge Termination,NiMH Hold Off Current,240,mAmp
Configuration,Charge Termination,NiMH Hold Off  Temp,25.0,1degC
Configuration,Charge Termination,NiMH Cell Negative Delta Volt,17,mVolt
Configuration,Charge Termination,NiMH Cell Negative Delta Time,16,Seconds
Configuration,Charge Termination,NiMH Cell Neg Delta Qual Volt,1200,mVolt
Configuration,Data,Manufacture Date,1980-1-1,Day + Mo*32 + (Yr -1980)*256
Configuration,Data,Serial Number,0001,hex
Configuration,Data,Cycle Count,26,Count
Configuration,Data,CC Threshold,900,mAmpHr
Configuration,Data,Max Error Limit,100,%
Configuration,Data,Design Capacity,7000,MilliAmpHour
Configuration,Data,Design Energy,14000,MilliWattHour
Configuration,Data,SOH Load I,-400,MilliAmp
Configuration,Data,Cell Charge Voltage T1-T2,200,mV
Configuration,Data,Cell Charge Voltage T2-T3,200,mV
Configuration,Data,Cell Charge Voltage T3-T4,200,mV
Configuration,Data,Charge Current T1-T2,10,Percent
Configuration,Data,Charge Current  T2-T3,50,Percent
Configuration,Data,Charge Current  T3-T4,30,Percent
Configuration,Data,JEITA T1,0,degC
Configuration,Data,JEITA T2,10,degC
Configuration,Data,JEITA T3,45,degC
Configuration,Data,JEITA T4,55,degC
Configuration,Data,Design Energy Scale,1,Number
Configuration,Data,Device Name,bq34z100-G1,-
Configuration,Data,Manufacturer Name,Texas Inst.,-
Configuration,Data,Device Chemistry,PbAc,-
Configuration,Discharge,SOC1 Set Threshold,150,mAh
Configuration,Discharge,SOC1 Clear Threshold,175,mAh
Configuration,Discharge,SOCF Set Threshold,75,mAh
Configuration,Discharge,SOCF Clear Threshold,100,mAh
Configuration,Discharge,Cell BL Set Volt Threshold,1200,mVolt
Configuration,Discharge,Cell BL Set Volt Time,2,Seconds
Configuration,Discharge,Cell BL Clear Volt Threshold,1500,mVolt
Configuration,Discharge,Cell BH Set Volt Threshold,1300,mVolt
Configuration,Discharge,Cell BH Volt Time,2,Seconds
Configuration,Discharge,Cell BH  Clear Volt Threshold,1300,mVolt
Configuration,Discharge,Cycle Delta,0.05,%
Configuration,Manufacturer Data,Pack Lot Code,0000,hex
Configuration,Manufacturer Data,PCB Lot Code,0000,hex
Configuration,Manufacturer Data,Firmware Version,0000,hex
Configuration,Manufacturer Data,Hardware Revision,0000,hex
Configuration,Manufacturer Data,Cell Revision,0000,hex
Configuration,Manufacturer Data,DF Config Version,0000,hex
Configuration,Lifetime Data,Lifetime Max Temp,30.0,1degC
Configuration,Lifetime Data,Lifetime Min Temp,20.0,1degC
Configuration,Lifetime Data,Lifetime Max Chg Current,1232,mAmp
Configuration,Lifetime Data,Lifetime Max Dsg Current,-2001,mA
Configuration,Lifetime Data,Lifetime Max Pack Voltage,805,20mV
Configuration,Lifetime Data,Lifetime Min Pack Voltage,175,20mV
Configuration,Lifetime Temp Samples,LT Flash Cnt,26,Count
Configuration,Registers,Pack Configuration,09d9,flags
Configuration,Registers,Pack Configuration B,af,flags
Configuration,Registers,Pack Configuration C,37,flags
Configuration,Registers,LED_Comm Configuration,00,flags
Configuration,Registers,Alert Configuration,0000,flags
Configuration,Registers,Number of series cell,6,num
Configuration,Lifetime Resolution,LT Temp Res,1.0,1degC
Configuration,Lifetime Resolution,LT Cur Res,100,mA
Configuration,Lifetime Resolution,LT V Res,1,20mV
Configuration,Lifetime Resolution,LT Update Time,60,Seconds
Configuration,LED Display,LED Hold Time,4,Num
Configuration,Power,Flash Update OK Cell Volt,1400,mVolt
Configuration,Power,Sleep Current,1,mAmp
Configuration,Power,FS Wait,0,Seconds
System Data,Manufacturer Info,Block A 0,00,hex
System Data,Manufacturer Info,Block A 1,00,hex
System Data,Manufacturer Info,Block A 2,00,hex
System Data,Manufacturer Info,Block A 3,00,hex
System Data,Manufacturer Info,Block A 4,00,hex
System Data,Manufacturer Info,Block A 5,00,hex
System Data,Manufacturer Info,Block A 6,00,hex
System Data,Manufacturer Info,Block A 7,00,hex
System Data,Manufacturer Info,Block A 8,00,hex
System Data,Manufacturer Info,Block A 9,00,hex
System Data,Manufacturer Info,Block A 10,00,hex
System Data,Manufacturer Info,Block A 11,00,hex
System Data,Manufacturer Info,Block A 12,00,hex
System Data,Manufacturer Info,Block A 13,00,hex
System Data,Manufacturer Info,Block A 14,00,hex
System Data,Manufacturer Info,Block A 15,00,hex
System Data,Manufacturer Info,Block A 16,00,hex
System Data,Manufacturer Info,Block A 17,00,hex
System Data,Manufacturer Info,Block A 18,00,hex
System Data,Manufacturer Info,Block A 19,00,hex
System Data,Manufacturer Info,Block A 20,00,hex
System Data,Manufacturer Info,Block A 21,00,hex
System Data,Manufacturer Info,Block A 22,00,hex
System Data,Manufacturer Info,Block A 23,00,hex
System Data,Manufacturer Info,Block A 24,00,hex
System Data,Manufacturer Info,Block A 25,00,hex
System Data,Manufacturer Info,Block A 26,00,hex
System Data,Manufacturer Info,Block A 27,00,hex
System Data,Manufacturer Info,Block A 28,00,hex
System Data,Manufacturer Info,Block A 29,00,hex
System Data,Manufacturer Info,Block A 30,00,hex
System Data,Manufacturer Info,Block A 31,00,hex
Gas Gauging,IT Cfg,Load Select,3,Number
Gas Gauging,IT Cfg,Load Mode,0,Number
Gas Gauging,IT Cfg,Res Current,10,mAmp
Gas Gauging,IT Cfg,Max Res Factor,50,num
Gas Gauging,IT Cfg,Min Res Factor,1,num
Gas Gauging,IT Cfg,Ra Filter,500,num
Gas Gauging,IT Cfg,Min PassedChg NiMH-LA 1st Qmax,50,%
Gas Gauging,IT Cfg,Maximum Qmax Change,100,%
Gas Gauging,IT Cfg,Cell Terminate Voltage,1000,mVolt
Gas Gauging,IT Cfg,Cell Term V Delta,100,mVolt
Gas Gauging,IT Cfg,ResRelax Time,500,Seconds
Gas Gauging,IT Cfg,User Rate-mA,0,MilliAmp
Gas Gauging,IT Cfg,User Rate-Pwr,0,mW/cW
Gas Gauging,IT Cfg,Reserve Cap-mAh,7000,MilliAmpHour
Gas Gauging,IT Cfg,Reserve Energy,0,mWh/cWh
Gas Gauging,IT Cfg,Max Scale Back Grid,4,num
Gas Gauging,IT Cfg,Cell Min DeltaV,0,mVolt
Gas Gauging,IT Cfg,Ra Max Delta,15,%
Gas Gauging,IT Cfg,Design Resistance,23,mOhms
Gas Gauging,IT Cfg,Reference Grid,4,-
Gas Gauging,IT Cfg,Qmax Max Delta %,10,mAmpHour
Gas Gauging,IT Cfg,Max Res Scale,32000,Num
Gas Gauging,IT Cfg,Min Res Scale,1,Num
Gas Gauging,IT Cfg,Fast Scale Start SOC,10,%
Gas Gauging,IT Cfg,Charge Hys V Shift,40,mVolt
Gas Gauging,IT Cfg,Smooth Relax Time,1000,s
Gas Gauging,Current Thresholds,Dsg Current Threshold,60,mAmp
Gas Gauging,Current Thresholds,Chg Current Threshold,75,mAmp
Gas Gauging,Current Thresholds,Quit Current,40,mAmp
Gas Gauging,Current Thresholds,Dsg Relax Time,60,Seconds
Gas Gauging,Current Thresholds,Chg Relax Time,60,Seconds
Gas Gauging,Current Thresholds,Cell Max IR Correct,400,mV
Gas Gauging,State,Qmax Cell 0,7339,mAmpHr
Gas Gauging,State,Cycle Count,21,num
Gas Gauging,State,Update Status,06,num
Gas Gauging,State,Cell V at Chg Term,2305,mVolt
Gas Gauging,State,Avg I Last Run,-899,mAmp
Gas Gauging,State,Avg P Last Run,-1801,MilliWattHour
Gas Gauging,State,Cell Delta Voltage,1,mVolt
Gas Gauging,State,T Rise,20,Num
Gas Gauging,State,T Time Constant,1000,Num
Ra Tables,Ra0 Table,Ra Flag,0055,Hex
Ra Tables,Ra0 Table,Ra 0,34,Num
Ra Tables,Ra0 Table,Ra 1,31,Num
Ra Tables,Ra0 Table,Ra 2,28,Num
Ra Tables,Ra0 Table,Ra 3,24,Num
Ra Tables,Ra0 Table,Ra 4,23,Num
Ra Tables,Ra0 Table,Ra 5,23,Num
Ra Tables,Ra0 Table,Ra 6,23,Num
Ra Tables,Ra0 Table,Ra 7,16,Num
Ra Tables,Ra0 Table,Ra 8,27,Num
Ra Tables,Ra0 Table,Ra 9,40,Num
Ra Tables,Ra0 Table,Ra 10,57,Num
Ra Tables,Ra0 Table,Ra 11,98,Num
Ra Tables,Ra0 Table,Ra 12,349,Num
Ra Tables,Ra0 Table,Ra 13,778,Num
Ra Tables,Ra0 Table,Ra 14,1247,Num
Ra Tables,Ra0x Table,Ra Flag,ffff,Hex
Ra Tables,Ra0x Table,Ra 0,34,Num
Ra Tables,Ra0x Table,Ra 1,31,Num
Ra Tables,Ra0x Table,Ra 2,28,Num
Ra Tables,Ra0x Table,Ra 3,24,Num
Ra Tables,Ra0x Table,Ra 4,23,Num
Ra Tables,Ra0x Table,Ra 5,23,Num
Ra Tables,Ra0x Table,Ra 6,23,Num
Ra Tables,Ra0x Table,Ra 7,25,Num
Ra Tables,Ra0x Table,Ra 8,27,Num
Ra Tables,Ra0x Table,Ra 9,30,Num
Ra Tables,Ra0x Table,Ra 10,35,Num
Ra Tables,Ra0x Table,Ra 11,45,Num
Ra Tables,Ra0x Table,Ra 12,121,Num
Ra Tables,Ra0x Table,Ra 13,268,Num
Ra Tables,Ra0x Table,Ra 14,429,Num
Calibration,Data,CC Gain,10.173,mohm
Calibration,Data,CC Delta,10.153,mohm
Calibration,Data,CC Offset,-1468,num
Calibration,Data,Board Offset,-6,num
Calibration,Data,Int Temp Offset,-0.3,degC
Calibration,Data,Ext Temp Offset,-0.3,degC
Calibration,Data,Voltage Divider,19235,mVolt
Calibration,Current,Deadband,5,mAmp
Security,Codes,Sealed to Unsealed,00000000,hex
Security,Codes,Unsealed to Full,00000000,hex
Security,Codes,Authen Key3,00000000,hex
Security,Codes,Authen Key2,00000000,hex
Security,Codes,Authen Key1,00000000,hex
Security,Codes,Authen Key0,00000000,hex
    Tom,

    Sorry I made a reply but it seems lost.  So I try again

    The exported file is a .gg.csv changed in .txt.   I hope it's what you expect.

    Thank you to look at.

    Mickael

  • 0 in reply to MickaelWhite
    TI__Guru 73830 points
    Mickael
    I need the srec and a log file showing the problem. I may be able to find the problem with some Mathcad programs.
    Tom
  • 0 in reply to ThomasCosby
    Prodigy 240 points

    Tom,

    I get a complete Qmax and Ra table Calibration again. Thank you to look at  .srec  and  .log files. 

    Mickael0100_0_16-bq34z100G1.7z8625.Qmax_Ra_Calibration.7z

  • 0 in reply to MickaelWhite
    TI__Guru 73830 points

    Mickael

    I checked your log data with the Mathcad program and it did not find a good ChemID match. I checked ChemID 805 with another program and it shows that ChemID 805 can yield negative resistances in the Ra table. The device will reject negative resistances, but it could prevent Ra table updates. You can try running some profiles to see how it performs. Maybe there is just something wrong with that set of data.
    Tom