• State
  • Locked Locked
  • Replies 11 replies
  • Subscribers 65 subscribers
  • Views 4301 views
  • Users 0 members are here
Support feedback
Options
Options
Related

This thread has been locked.

If you have a related question, please click the "Ask a related question" button in the top right corner. The newly created question will be automatically linked to this question.

BQ34110: BQ34110 - SOC drop to 0% when discharging

Michael Desjardins
Intellectual 580 points
Part Number: BQ34110
Other Parts Discussed in Thread: GPCCEDV

Hi!

I'm evaluating the BQ34110 Fuel gauge with the BQ34110-EVM and 3 NiMH batteries (AAA). 

I have the CEDV parameters for the batteries, done a charge-discharge-charge cycle with the BQ34110 connected to the batteries, when the battery is fully charged, the remaining capacity is near the designed capacity (fully charged capacity).

The SOC seems to be evaluated on the Open circuit voltage only and not with the remaining capacity, the batteries are fully charged, the SOC is at 100% but when I discharge the batteries (at 0.75C rate), the voltage drop and the SOC drop to 0%!

Do you know what can be wrong or where I have to look to solve this issue?

Thank you!

Michael

  • 0
    Expert 2475 points
    Can you provide the log file and a gg file from the pack?
  • 0 in reply to TEC
    Intellectual 580 points

    * Texas Instruments Data Flash File
    * File created Fri Aug 11 09:33:36 2017
    *
    * Device Number 110
    * Firmware Version 0.02
    * Build Number 9
    * Order Number 0
    *
    * bqz Device Number 110
    * bqz Firmware Version 0.02
    * bqz Build Number 9
    *
    * Field Order: Class name Subclass name Parameter name Parameter Value Display Units
    Calibration Data CC Gain 9.999 mOhm
    Calibration Data CC Delta 10 mOhm
    Calibration Data CC Offset -42.66 mA
    Calibration Data Board Offset 0 uA
    Calibration Data Int Temp Offset 0 °C
    Calibration Data Ext Temp Offset 0 °C
    Calibration Data Pack V Offset 0 mV
    Calibration Data Voltage Divider 5000 mV
    Calibration Temp Model Int Coeff 1 0 Num
    Calibration Temp Model Int Coeff 2 0 Num
    Calibration Temp Model Int Coeff 3 -12324 Num
    Calibration Temp Model Int Coeff 4 613.1 degK
    Calibration Temp Model Int Min AD 0 -
    Calibration Temp Model Int Max Temp 6131 0.1degK
    Calibration Temp Model Ext Coeff 1 20982 Num
    Calibration Temp Model Ext Coeff 2 -13836 Num
    Calibration Temp Model Ext Coeff 3 5202 Num
    Calibration Temp Model Ext Coeff 4 233.7 degK
    Calibration Temp Model Ext Min AD 12909 -
    Calibration Temp Model Vcomp Coeff 1 0 Num
    Calibration Temp Model Vcomp Coeff 2 14902 Num
    Calibration Temp Model Vcomp Coeff 3 -623 Num
    Calibration Temp Model Vcomp Coeff 4 37 Num
    Calibration Temp Model Vcomp Input Multiplier 48 Num
    Calibration Temp Model Vcomp Output Divisor 256 Num
    Calibration Current Filter 239 Num
    Calibration Current Deadband 5 mA
    Calibration Current CC Deadband 34 149nV
    Charger Control Charge Inhibit Cfg Chg Inhibit Temp Low 0 °C
    Charger Control Charge Inhibit Cfg Chg Inhibit Temp High 45 °C
    Charger Control Charge Inhibit Cfg Temp Hys 5 °C
    Charger Control JEITA Temperature T1 Temp 0 °C
    Charger Control JEITA Temperature T2 Temp 10 °C
    Charger Control JEITA Temperature T3 Temp 45 °C
    Charger Control JEITA Temperature T4 Temp 55 °C
    Charger Control JEITA Temperature Charge Current T1-T2 300 mA
    Charger Control JEITA Temperature Charge Current T2-T3 1100 mA
    Charger Control JEITA Temperature Charge Current T3-T4 660 mA
    Charger Control JEITA Temperature Charge Voltage T1-T2 4100 mV
    Charger Control JEITA Temperature Charge Voltage T2-T3 4200 mV
    Charger Control JEITA Temperature Charge Voltage T3-T4 4100 mA
    Charger Control Charge Termination Maintenance Current 0 mA
    Charger Control Charge Termination Taper Current 100 mA
    Charger Control Charge Termination Minimum Taper Capacity 25 0.01mAh
    Charger Control Charge Termination Taper Voltage 100 mV
    Charger Control Charge Termination Current Taper Window 40 s
    Charger Control WHr Charge Termination Max Charge Voltage 4200 mV
    Charger Control WHr Charge Termination WHr CV Step 50 mV
    Charger Control WHr Charge Termination WHr Termination Capacity 1100 mAh
    Charger Control WHr Charge Termination FC WHr Clear 1000 mAh
    Charger Control NiMH Charge Termination Delta Temperature 3 °C
    Charger Control NiMH Charge Termination Delta Temperature Time 100 s
    Charger Control NiMH Charge Termination Holdoff Time 180 s
    Charger Control NiMH Charge Termination Holdoff Current 240 mA
    Charger Control NiMH Charge Termination Holdoff Temperature 25 °C
    Charger Control NiMH Charge Termination Cell Negative Delta Voltage 17 mV
    Charger Control NiMH Charge Termination Cell Negative Delta Time 16 s
    Charger Control NiMH Charge Termination Cell Negative Delta Qual Voltage 3600 mV
    Charger Control Learned Charge Voltage Last Charge Voltage T1-T2 4100 mV
    Charger Control Learned Charge Voltage Last Charge Voltage T2-T3 4200 mV
    Charger Control Learned Charge Voltage Last Charge Voltage T3-T4 4100 mV
    Charger Control Charge Level Control Charge Voltage Level A 3900 mV
    Charger Control Charge Level Control Charge Voltage Level B 3950 mV
    Charger Control Charge Level Control Charge Voltage Level C 4000 mV
    Charger Control Charge Level Control Charge Voltage Level D 4050 mV
    Charger Control Charge Level Control Charge Voltage Level E 4100 mV
    Charger Control Charge Level Control Charge Voltage Level F 4150 mV
    Charger Control Charge Level Control Charge Voltage Level G 4200 mV
    Charger Control Charge Level Control Charge Voltage Level H 4250 mV
    Settings Configuration Direct Charge Pin Control 0 hex
    Settings Configuration Charge Level Pin Control 0 hex
    Settings Configuration Pin Control Config 0 hex
    Settings Configuration Alert1_0 Config 0 hex
    Settings Configuration Alert1_1 Config 0 hex
    Settings Configuration Alert1_2 Config 0 hex
    Settings Configuration Alert1_3 Config 0 hex
    Settings Configuration Alert1_4 Config 0 hex
    Settings Configuration Alert1_5 Config 0 hex
    Settings Configuration Alert1_6 Config 0 hex
    Settings Configuration Alert2_0 Config 0 hex
    Settings Configuration Alert2_1 Config 0 hex
    Settings Configuration Alert2_2 Config 0 hex
    Settings Configuration Alert2_3 Config 0 hex
    Settings Configuration Alert2_4 Config 0 hex
    Settings Configuration Alert2_5 Config 0 hex
    Settings Configuration Alert2_6 Config 0 hex
    Settings Configuration SOC Flag Config A 0c8c hex
    Settings Configuration SOC Flag Config B 8c hex
    Settings Configuration CEDV Gauging Configuration 1022 hex
    Settings Configuration EOS Configuration 1 hex
    Settings BLT Init Discharge Set 150 mAh
    Settings BLT Init Charge Set 175 mAh
    Settings Accumulated Charge Accum Charge Positive Threshold 1000 mAh
    Settings Accumulated Charge Accum Charge Negative Threshold 1000 mAh
    Settings Manufacturing Mfg Status Init 0 hex
    Safety OTC OT Chg 55 °C
    Safety OTC OT Chg Time 2 s
    Safety OTC OT Chg Recovery 50 °C
    Safety OTD OT Dsg 60 °C
    Safety OTD OT Dsg Time 2 s
    Safety OTD OT Dsg Recovery 55 °C
    Safety UTC UT Chg 0 °C
    Safety UTC UT Chg Time 2 s
    Safety UTC UT Chg Recovery 5 °C
    Safety UTD UT Dsg 0 °C
    Safety UTD UT Dsg Time 2 s
    Safety UTD UT Dsg Recovery 5 °C
    Safety BATLOW Battery Low Set Threshold 3150 mV
    Safety BATLOW Battery Low Time 2 s
    Safety BATLOW Battery Low Clear Threshold 3400 mV
    Safety BATHIGH Battery High Set Threshold 4300 mV
    Safety BATHIGH Battery High Time 2 s
    Safety BATHIGH Battery High Clear Threshold 4200 mV
    Safety SOCLOW SOC Low Threshold 10 %
    Safety SOCLOW SOC Low Recovery 30 %
    Configuration Registers Operation Config A 8204 hex
    Configuration Registers Device Type 110 Hex
    Configuration Registers Number of Series Cells 3 Num
    Configuration Power Flash Update OK Voltage 1000 mV
    Configuration Power Sleep Current 10 mA
    Configuration Power Bus Low Time 5 s
    Configuration Power Offset Cal Inhibit Temp Low 5 °C
    Configuration Power Offset Cal Inhibit Temp High 45 °C
    Configuration Power Sleep Voltage Time 20 s
    Configuration Power Sleep Current Time 20 s
    Configuration Current Thresholds Discharge Detection Threshold 60 mA
    Configuration Current Thresholds Charge Detection Threshold 75 mA
    Configuration Current Thresholds Quit Current 40 mA
    Configuration Current Thresholds Discharge Relax Time 60 s
    Configuration Current Thresholds Charge Relax Time 60 s
    Configuration Current Thresholds Quit Relax Time 1 s
    Configuration Data Default Temperature 298.2 K
    Configuration Data Device Name bq34110 -
    Configuration Data Data Flash Version ffff -
    Configuration Data Serial Number 1 hex
    Configuration Data Manufacture Date ######## Day + Mo*32 + (Yr -1980)*512
    Configuration Integrity Data DF Static Checksum 0 hex
    Configuration Integrity Data All DF Checksum 0 hex
    Configuration Integrity Data IF Checksum fbd3e090 hex
    Configuration Integrity Data Full Reset Counter 20 Num
    Configuration Integrity Data Reset Counter WD 0 Num
    System Data Manufacturer Data Manufacturer Info Block A01 0 Hex
    System Data Manufacturer Data Manufacturer Info Block A02 0 Hex
    System Data Manufacturer Data Manufacturer Info Block A03 0 Hex
    System Data Manufacturer Data Manufacturer Info Block A04 0 Hex
    System Data Manufacturer Data Manufacturer Info Block A05 0 Hex
    System Data Manufacturer Data Manufacturer Info Block A06 0 Hex
    System Data Manufacturer Data Manufacturer Info Block A07 0 Hex
    System Data Manufacturer Data Manufacturer Info Block A08 0 Hex
    System Data Manufacturer Data Manufacturer Info Block A09 0 Hex
    System Data Manufacturer Data Manufacturer Info Block A10 0 Hex
    System Data Manufacturer Data Manufacturer Info Block A11 0 Hex
    System Data Manufacturer Data Manufacturer Info Block A12 0 Hex
    System Data Manufacturer Data Manufacturer Info Block A13 0 Hex
    System Data Manufacturer Data Manufacturer Info Block A14 0 Hex
    System Data Manufacturer Data Manufacturer Info Block A15 0 Hex
    System Data Manufacturer Data Manufacturer Info Block A16 0 Hex
    System Data Manufacturer Data Manufacturer Info Block A17 0 Hex
    System Data Manufacturer Data Manufacturer Info Block A18 0 Hex
    System Data Manufacturer Data Manufacturer Info Block A19 0 Hex
    System Data Manufacturer Data Manufacturer Info Block A20 0 Hex
    System Data Manufacturer Data Manufacturer Info Block A21 0 Hex
    System Data Manufacturer Data Manufacturer Info Block A22 0 Hex
    System Data Manufacturer Data Manufacturer Info Block A23 0 Hex
    System Data Manufacturer Data Manufacturer Info Block A24 0 Hex
    System Data Manufacturer Data Manufacturer Info Block A25 0 Hex
    System Data Manufacturer Data Manufacturer Info Block A26 0 Hex
    System Data Manufacturer Data Manufacturer Info Block A27 0 Hex
    System Data Manufacturer Data Manufacturer Info Block A28 0 Hex
    System Data Manufacturer Data Manufacturer Info Block A29 0 Hex
    System Data Manufacturer Data Manufacturer Info Block A30 0 Hex
    System Data Manufacturer Data Manufacturer Info Block A31 0 Hex
    System Data Manufacturer Data Manufacturer Info Block A32 0 Hex
    Lifetimes Lifetime Resolution Temperature Resolution 1 C
    Lifetimes Lifetime Resolution Current Resolution 100 mA
    Lifetimes Lifetime Resolution Voltage Resolution 1 20mV
    Lifetimes Temperature Max Temperature 30 C
    Lifetimes Temperature Min Temperature 20 C
    Lifetimes Current Max Charge Current 0 mA
    Lifetimes Current Max Discharge Current 0 mA
    Lifetimes Voltage Max Pack Voltage 160 20mV
    Lifetimes Voltage Min Pack Voltage 175 20mV
    Gas Gauging CEDV Profile Design Capacity mAh 900 mAh
    Gas Gauging CEDV Profile EMF 3510 -
    Gas Gauging CEDV Profile C0 436 -
    Gas Gauging CEDV Profile R0 38115 -
    Gas Gauging CEDV Profile T0 5854 -
    Gas Gauging CEDV Profile R1 1 -
    Gas Gauging CEDV Profile TC 9 -
    Gas Gauging CEDV Profile C1 0 -
    Gas Gauging CEDV Profile Age Factor 0 -
    Gas Gauging CEDV Profile Fixed EDV 0 3031 -
    Gas Gauging CEDV Profile EDV 0 Hold Time 1 s
    Gas Gauging CEDV Profile Fixed EDV 1 3385 -
    Gas Gauging CEDV Profile EDV 1 Hold Time 1 s
    Gas Gauging CEDV Profile Fixed EDV 2 3501 -
    Gas Gauging CEDV Profile EDV 2 Hold Time 1 s
    Gas Gauging CEDV Profile Voltage 0% DOD 1274 mV
    Gas Gauging CEDV Profile Voltage 10% DOD 1182 mV
    Gas Gauging CEDV Profile Voltage 20% DOD 1176 mV
    Gas Gauging CEDV Profile Voltage 30% DOD 1176 mV
    Gas Gauging CEDV Profile Voltage 40% DOD 1172 mV
    Gas Gauging CEDV Profile Voltage 50% DOD 1167 mV
    Gas Gauging CEDV Profile Voltage 60% DOD 1159 mV
    Gas Gauging CEDV Profile Voltage 70% DOD 1146 mV
    Gas Gauging CEDV Profile Voltage 80% DOD 1125 mV
    Gas Gauging CEDV Profile Voltage 90% DOD 1087 mV
    Gas Gauging CEDV Profile Voltage 100% DOD 1001 mV
    Gas Gauging Design Design Voltage 1200 mV
    Gas Gauging Cycle Cycle Count Percentage 90 %
    Gas Gauging FD Set Voltage Threshold 3000 mV
    Gas Gauging FD Clear Voltage Threshold 3100 mV
    Gas Gauging FD Set % RSOC Threshold 0 %
    Gas Gauging FD Clear % RSOC Threshold 5 %
    Gas Gauging FC Set Voltage Threshold 4200 mV
    Gas Gauging FC Clear Voltage Threshold 4100 mV
    Gas Gauging FC Set % RSOC Threshold 100 %
    Gas Gauging FC Clear % RSOC Threshold 95 %
    Gas Gauging TD Set Voltage Threshold 3200 mV
    Gas Gauging TD Clear Voltage Threshold 3300 mV
    Gas Gauging TD Set % RSOC Threshold 6 %
    Gas Gauging TD Clear % RSOC Threshold 8 %
    Gas Gauging TC Set Voltage Threshold 4200 mV
    Gas Gauging TC Clear Voltage Threshold 4100 mV
    Gas Gauging TC Set % RSOC Threshold 100 %
    Gas Gauging TC Clear % RSOC Threshold 95 %
    Gas Gauging State Profile Cycle Count 0 -
    Gas Gauging State Profile Learned Full Charge Capacity 900 mAh
    Gas Gauging State Profile Stored Remaining Capacity 0 mAh
    Gas Gauging CEDV Cfg Battery Low % 7 %
    Gas Gauging CEDV Cfg Learning Low Temp 119 0.1°C
    Gas Gauging CEDV Cfg OverLoad Current 3400 mA
    Gas Gauging CEDV Cfg Self Discharge Rate 20 0.01%/day
    Gas Gauging CEDV Cfg Electronics Load 0 3uA
    Gas Gauging CEDV Cfg Near Full 200 mAh
    Gas Gauging CEDV Cfg Reserve Capacity 0 mAh
    Gas Gauging CEDV Cfg Chg Eff 100 %
    Gas Gauging CEDV Cfg Dsg Eff 100 %
    Gas Gauging CEDV Cfg RemCap Init Percent 100 %
    Gas Gauging CEDV Smoothing Config Smoothing Config 8 hex
    Gas Gauging CEDV Smoothing Config Smoothing Start Voltage 3700 mV
    Gas Gauging CEDV Smoothing Config Smoothing Delta Voltage 100 mV
    Gas Gauging CEDV Smoothing Config Max Smoothing Current 8000 mA
    Gas Gauging CEDV Smoothing Config EOC Smooth Current 0.2 %
    Gas Gauging CEDV Smoothing Config EOC Smooth Current Time 60 s
    End Of Service Resistance Learning Auto Learn Time 1500 Hours
    End Of Service Resistance Learning Auto Learn Retry Time 1 Hours
    End Of Service Resistance Learning Minimum Learn Time 750 Hours
    End Of Service Resistance Learning Alert-Warn Learn Time 750 Hours
    End Of Service Resistance Learning Initial Learn Pulse Number 1 Counts
    End Of Service Resistance Learning Learn Charge Voltage Delta 100 mV
    End Of Service Resistance Learning Learn Charge Time Limit 3600 s
    End Of Service Resistance Learning Learn Discharge Current 220 mA
    End Of Service Resistance Learning Learn Discharge Current Boundary 25 %
    End Of Service Resistance Learning Learn Discharge Time 500 s
    End Of Service Resistance Learning Learn Request Timeout 4 s
    End Of Service Resistance Learning Learn Min Temperature 10 1°C
    End Of Service Resistance Learning Learn Max Temperature 40 1°C
    End Of Service Resistance Learning Learn Target Temperature 25 1°C
    End Of Service Resistance Learning Rcell High Temp Coefficient 0 2^-16/0.1°C
    End Of Service Resistance Learning Rcell Low Temp Coefficient 0 2^-16/0.1°C
    End Of Service Direct Resistance Decision DRD Alert Level 45 %
    End Of Service Direct Resistance Decision DRD Alert Counts 3 Counts
    End Of Service Direct Resistance Decision DRD Warning Level 60 %
    End Of Service Direct Resistance Decision DRD Warning Counts 3 Counts
    End Of Service Direct Resistance Decision Initial Rcell 0 mOhm
    End Of Service Direct Resistance Decision Initial Rcell Learned 0 -
    End Of Service Resistance Slope Decision RSD Alert Level 15 %
    End Of Service Resistance Slope Decision RSD Alert Counts 3 Counts
    End Of Service Resistance Slope Decision RSD Warning Level 30 %
    End Of Service Resistance Slope Decision RSD Warning Counts 3 Counts
    End Of Service Resistance Slope Decision RSDL Alert Level 15 %
    End Of Service Resistance Slope Decision RSDL Warning Level 30 %
    End Of Service Resistance Slope Decision Initial RRate 0 -
    End Of Service Resistance Slope Decision Initial RRate Learned 0 -
    End Of Service Safety Status Warning Status 0 hex

    Here is the gg file.

    I will send the log file later today.

    Thank you!

    Michael

  • 0 in reply to Michael Desjardins
    Expert 2475 points
    I reviewed the gg file and there are a lot of parameters that are still setup to support Li-Ion cells. They will need to be adjusted to support your NiMH cells. The CEDV coefficients have been updated, but the values look like Li_Ion values and not NiMH. Did you enter 3S when having the GPCCEDV tool calculate these parameters?
  • 0 in reply to TEC
    Intellectual 580 points
    I've done the discharge curves with 1 NiMH battery, send it to the GPCCEDV tool and I have put the CEDV coefficients in the Gas Gauging data memory. In the Configuration, I've entered 3 in the Number of Series Cells field.
  • 0 in reply to Michael Desjardins
    Intellectual 580 points
    I use 3 NiMH series cells in my application. Did the tool recalculate the parameters for 3 series cells?
  • 0 in reply to Michael Desjardins
    Expert 2475 points
    That should be the correct process, so maybe the CEDV coefficients are okay. The EMF just looks high to me. The gauge will gauge at a 1S level, so it should not adjust the parameters. Please send the log file when it is available.
  • 0 in reply to Michael Desjardins
    Expert 2475 points
    The log file shows that the gauge is updating the EDV Thresholds, but it is using the FIXED EDV settings. Try setting the FIXED_EDV bit to 0 and the EDV_CMP bit to 1 to allow the gauge to calculate the EDV Thresholds. The log file also indicates that the gauge did not reach charge termination and the pack may not be fully charged. There are also a lot of spurious data values in the log file. This could indicate that there are noise issues in your setup.
  • 0 in reply to TEC
    Prodigy 150 points
    About the noise issue, we are using the eval kit with wires that are longer than the real product will have. We are expecting soon the real product PCB fully assembled, so shorter wires may help to cut down the noise (if noise is the issue).

    Since the beginning, Michael has been using the BQ studio software in these parametrisations tests. Is there documentation about doing the equivalent on our PCB where we have a micro controller connected to the BQ I2C, not the eval kit I2C?

    Is there also documentation on how to write the golden parameters in the BQ using the I2C from the MCU, not BQ studio? We are planning the testing - production benches.

    Michael is currently out of the office and will try the register changes you proposed when he is back the 28.
  • 0 in reply to Cédric St-Amand
    Prodigy 150 points
    In order to validate with short real short PCB trace these informations would be userful:
    -Since the beginning, Michael has been using the BQ studio software in these parametrisations tests. Is there documentation about doing the equivalent on our PCB where we have a micro controller connected to the BQ I2C, not the eval kit I2C?
    -Is there also documentation on how to write the golden parameters in the BQ using the I2C from the MCU, not BQ studio? This would allow to test using golden on a second board, not using the parametrisation tests.

    Michael will be back on Monday and work on this as a top priority, if you could point out documentations or example code it would be very helpful.