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bq78350 Wrong State of Charge

Other Parts Discussed in Thread: BQ76940EVM, BQ78350-R1, BQSTUDIO, BQ78350, GPCCEDV

hi

i have  bq76940EVM which is connected to my MCU.

for charging purpose i connect the power supply to the PACK- and PACK+ terminal while battery pack is connected to BATT- and BATT+ terminal.

i tried hundreds of ways to start charging and finally Charging started while ChargingStatus() returning 0 means neither PCHG and FCHG bits are not set.(don't no why)

i set the Design Capacity of Gauge to 3350 which is the capacity of my Battery cells.

first time i started to charging battery the Absolute state of charge was about 60 while the voltage of each cells was more than 4.0 volts , after some Discharge and Charging again voltage per each cell is more than 4.0v but the Absolute SOC is about 10 .

why it's acting like that ??



 
 

  • You probably need to reduce the value of the Design capacity parameter to increase the ASOC. If you have a log file, then I can probably offer a better assessment.
  • Is  "Design Capacity" the only parameter that need to be modified in order to getting correct SOC ??

    i set it to capacity of my cells. 3350.

  • as you mentioned in this forum for getting a good gauging we must set ChemID of the cells properly. but the problem is the only access to ChemId as Datasheet explained is through ManufacturerAccess() which have READ permission only , how can i change it to one i'am working with ??
  • The bq78350-R1 only uses the chemistry data after the cells have been attached or after the device has been reset, so a good ChemID match is not as critical for CEDV gauges. It uses coulomb counting to monitor the capacity after that. If you do want to change the chemistry data, then you have to uses bqStudio to update it. If you are not using bqStudio, then I can send you an srec file with the chemistry data updated to your ChemID.
  • Dear Thomas

    it would be great if you send me such a file . in fact i need a file in which all parameters of a functional bq78350 has been set that giving logical SOC (in order to compare with my parameters).  is there any source code about configuring bq78350??

    the below data are a part of  my log file that are captured from my MCU (during discharge cycle)

    Related State Of Charge : 0  //I do not know why it is Zero?

    Absolute State Of Charge : 0 //I do not know why it is Zero?

    Learned Full Charge Capacity : 3350 // this one changing occasionally

    Design Capacity : 3350

    ChargingSttus : 0  //this one is zero,always (charging/discharging)

    Temperature Enable : 11

    Temperature : 31.050

    Precharge Temp : 12

    GaugingStatus : 0

    Charging Voltage : 4200

    Charging Current : 1500

    Oprtion Status: 4

    pack Voltage c : 51415

    pack Current c : 0

    Remaining Cap : 0  // why it is zero ????

    Design Voltage: 3600

    FCC LearnUp : 3094

    QMAX Pack : 3350

    CUV : 2500

    SOH : 92

    Voltage 15: 2.968  

    Voltage 14: 3.331  

    Voltage 13: 3.413  

    Voltage 12: 3.507  

    Voltage 11: 3.535  

    Voltage 10: 3.436  

    Voltage 9: 3.512  

    Voltage 8: 3.491  

    Voltage 7: 2.972  

    Voltage 6: 3.542  

    Voltage 5: 3.549  

    Voltage 4: 3.545  

    Voltage 3: 3.545  

    Voltage 2: 3.538  

    Voltage 1: 3.538

  • Most of these parameters are located in RAM and not flash memory, but I can update the ones that are. Which ChemID did you need loaded into the device? Have you run the discharge profiles and calculated the CEDV coefficients yet?
  • bay default it has 1210 , i want : 2012 which is ncr18650b(3350mah) NICOMN/carbon

    "Have you run the discharge profiles and calculated the CEDV coefficients yet" no i didn't perform that . how can i calculate CEDV coefficients ??
  • Here is the default bq78250-R1 srec with ChemID 2012 programmed. I will not  have the time to program your other parameters into the DF today. Here is the link to the GPCCEDV tool to explain how to collect the data and submit it to create the CEDV coefficients.

    https://e2e.ti.com/cfs-file/__key/communityserver-discussions-components-files/196/bq78350_5F00_R1_5F00_v1_5F00_03_5F00_ChemID_5F00_2012.srec

  • As far as i understand this srec file is a collection of bytes that should be uploaded to bq78350 in order to make it work (am i true ??)

    is there any manual to guide me how can i upload it with my MCU(not EV2300/2400)??
  • Thomas

    in last couple of day i wrote a software to parse the srec file you gave to me . but i found that some parameter i out of the value that is in DataSheet .

    any way i update my BQ78350(not R1 type) with your parameter but i steel getting wrong SOC.

    for example i'am reading "FCC LearnUp" (SBS 0x10) =  -3601 and "Remaining Capacity = 61935". with ASOC = 182 and RSOC = 100 and all cell voltage is around 3.5v.

    please thomas if there is any srec file that is working good in a device . send it to me to check and try it's parameters. and pleas note that my ChemID is 2012.

    if there is not  , help me another way.

    in attachment i send you the extracted parameter from file to sent to me.

    CC Gain  : 1.648318E+32
    Capacity Gain  : 9.214514E+22
    Cell1 Offset  : 0
    Cell2 Offset  : 0
    Cell3 Offset  : 0
    Cell4 Offset  : 0
    Cell5 Offset  : 0
    Cell6 Offset  : 0
    Cell7 Offset  : 0
    Cell8 Offset  : 0
    Cell9 Offset  : 0
    Cell10 Offset  : 0
    Cell11 Offset  : 0
    Cell12 Offset  : 0
    Cell13 Offset  : 0
    Cell14 Offset  : 0
    Cell15 Offset  : 0
    CC Offset  : 0
    Coulomb Counter Offset Samples  : 64
    T1 Temp Offset  : 0
    T2 Temp Offset  : 0
    T3 Temp Offset  : 136
    Ext Cell Divider Gain  : 0
    VAux Gain  : 327745535
    Int Gain  : -11130
    Int base offset  : 19142
    Int Minimum AD  : -19262
    Int Maximum Temp  : 28203
    Coeff a1  : 892
    Coeff a2  : 328
    Coeff a3  : 29970
    Coeff a4  : 22573
    Coeff a5  : -18643
    Coeff b1  : -18688
    Coeff b2  : 70
    Coeff b3  : 20687
    Coeff b4  : -31976
    Rc0  : 22528
    Adc0  : 24
    Deadband  : 5
    Coulomb Counter  : 1
    FET Options  : 05C2
    Sbs Gauging Configuration  : 05
    Smb Configuration  : 14
    LED Configuration  : 43
    Temperature Enable  : 0B
    DA Configuration  : 10
    AFE Cell Map  : CC02
    CEDV Gauging Configuration  : 9F00
    SOC Flag Config  : 645F
    Balancing Configuration  : FF
    PF SAFE A  : 06
    PF SAFE B  : D6
    PF SAFE C  : 0A
    Fuse Blow Timeout  : 10
    Addr Reads  : 0
    SMBTAR_ADDR0  : 0A
    SMBTAR_ADDR1  : 14
    SMBTAR_ADDR2  : 05
    SMBTAR_ADDR3  : A0
    SMBTAR_ADDR4  : 02
    SMBTAR_ADDR5  : 00
    SMBTAR_ADDR6  : 02
    SMBTAR_ADDR7  : 00
    Host Address  : 00
    Charger Address  : 64
    Alarm Timer  : 16
    Charger Request Timer  : 10
    Protection Configuration  : 02
    Enabled Protections A  : 26
    Enabled Protections B  : 02
    Enabled Protections C  : 01
    Enabled PF A  : 64
    Enabled PF B  : 02
    Mfg Status init  : 3B80
    Charge Inhibit/SuspendLow Temp  : 9
    Precharge Temp  : 196
    Charge Inhibit High Temp  : 11
    Charge Suspend High Temp  : 84
    Hysteresis Temp  : 0
    Voltage  : -1536
    Current  : 16384
    Current  : 19240
    Start Voltage  : 14
    Recovery Voltage  : 29696
    Charge Term Taper Current  : 25631
    Charge Term Voltage  : 60
    Cell Balance Threshold  : -1
    Cell Balance Window  : -1
    Cell Balance Min  : 255
    Cell Balance Interval  : 255
    Valid Update Voltage  : 20
    Shutdown Voltage  : 10300
    Shutdown Time  : 80
    PF Shutdown Voltage  : 8960
    PF Shutdown Time  : 0
    Charger Present Threshold  : 192
    Sleep Current  : 300
    Bus Timeout  : 1
    Voltage Time  : 9
    Current Time  : 0
    FET Off Time  : 0
    Delay  : 19
    Time  : 24
    LED Flash Period  : 0
    LED Blink Period  : 20652
    LED Delay  : 38681
    LED Hold Time  : 100
    LED Flash Alarm  : 16
    LED Thresh 1  : 254
    LED Thresh 2  : 6
    LED Thresh 3  : 214
    LED Thresh 4  : 250
    LED Thresh 5  : 10
    LCD Refresh Rate  : 0
    GPIO Configuration  : 64
    GPIO Output Enable  : 00
    GPIO Default Output Enable  : 32
    GPIO Type  : 00
    Manufacturer Info A  : 102
    Manufacturer Info Block A01  : 67
    Manufacturer Info Block A02  : 68
    Manufacturer Info Block A03  : 69
    Manufacturer Info Block A04  : 6A
    Manufacturer Info Block A05  : 6B
    Manufacturer Info Block A06  : 6C
    Manufacturer Info Block A07  : 6D
    Manufacturer Info Block A08  : 6E
    Manufacturer Info Block A09  : 6F
    Manufacturer Info Block A10  : 70
    Manufacturer Info Block A11  : 71
    Manufacturer Info Block A12  : 72
    Manufacturer Info Block A13  : 73
    Manufacturer Info  Block A14  : 74
    Manufacturer Info Block A15  : 75
    Manufacturer Info Block A16  : 76
    Manufacturer Info Block A17  : 77
    Manufacturer Info Block A18  : 7A
    Manufacturer Info Block A19  : 78
    Manufacturer Info Block A20  : 79
    Manufacturer Info Block A21  : 30
    Manufacturer Info Block A22  : 31
    Manufacturer Info Block A23  : 32
    Manufacturer Info Block A24  : 33
    Manufacturer Info Block A25  : 34
    Manufacturer Info Block A26  : 35
    Manufacturer Info Block A27  : 00
    Manufacturer Info Block A28  : 00
    Manufacturer Info Block A29  : 64
    Manufacturer Info Block A30  : 84
    Manufacturer Info Block A31  : 00
    Manufacturer Info Block A32  : F1
    Manufacture Date  : 29472
    Serial Number  : 496E
    Manufacturer Name  : 737472756D656E7473202020076271373820202020
    Device Name  : 202020202020202020044C494F4E00000000000000
    Device Chemistry  : 0000000000
    Remaining AH Cap. Alarm  : 2561
    Remaining WH Cap. Alarm  : 15360
    Remaining Time Alarm  : 0
    Initial Battery Mode  : 0009
    Specification Information  : C402
    Cell 1 Max Voltage  : 0
    Cell 2 Max Voltage  : 0
    Cell 3 Max Voltage  : 0
    Cell 4 Max Voltage  : 0
    Cell 5 Max Voltage  : 0
    Cell 6 Max Voltage  : 0
    Cell 7 Max Voltage  : 0
    Cell 8 Max Voltage  : 0
    Cell 9 Max Voltage  : 0
    Cell 10 Max Voltage  : 0
    Cell 11 Max Voltage  : 0
    Cell 12 Max Voltage  : 0
    Cell 13 Max Voltage  : 0
    Cell 14 Max Voltage  : 0
    Cell 15 Max Voltage  : 127
    Cell 1 Min Voltage  : 127
    Cell 2 Min Voltage  : 255
    Cell 3 Min Voltage  : 127
    Cell 4 Min Voltage  : 255
    Cell 5 Min Voltage  : 127
    Cell 6 Min Voltage  : 255
    Cell 7 Min Voltage  : 127
    Cell 8 Min Voltage  : 255
    Cell 9 Min Voltage  : 127
    Cell 10 Min Voltage  : 255
    Cell 11 Min Voltage  : 127
    Cell 12 Min Voltage  : 255
    Cell 13 Min Voltage  : 127
    Cell 14 Min Voltage  : 255
    Cell 15 Min Voltage  : 127
    Max Delta Cell Voltage  : 255
    Max Charge Current  : 32767
    Max Discharge Current  : 32767
    Max Avg Dsg Current  : 32767
    Max Avg Dsg Power  : 32767
    Max Temp Cell  : 127
    Min Temp Cell  : 255
    Max Delta Cell Temp  : 0
    No Of COV Events  : 0
    Last COV Event  : 0
    No Of CUV Events  : 0
    Last CUV Event  : 0
    No Of OCD Events  : 128
    Last OCD Event  : 32512
    No Of OCC Events  : 32896
    Last OCC Event  : 32512
    No Of AOLD Events  : 0
    Last AOLD Event  : 0
    No Of ASCD Events  : 0
    Last ASCD Event  : 0
    No Of OTC Events  : 0
    Last OTC Event  : 0
    No Of OTD Events  : 0
    Last OTD Event  : 0
    No Valid Charge Term  : 0
    Last Valid Charge Term  : 0
    No of FCC Updates  : 0
    Last FCC Update  : 0
    No Of Shutdowns  : 0
    Cb Time Cell 1  : 0
    Cb Time Cell 2  : 0
    Cb Time Cell 3  : 0
    Cb Time Cell 4  : 0
    Cb Time Cell 5  : 0
    Cb Time Cell 6  : 0
    Cb Time Cell 7  : 0
    Cb Time Cell 8  : 0
    Cb Time Cell 9  : 0
    Cb Time Cell 10  : 0
    Cb Time Cell 11  : 0
    Cb Time Cell 12  : 0
    Cb Time Cell 13  : 0
    Cb Time Cell 14  : 0
    Cb Time Cell 15  : 0
    Total Fw Runtime  : 0
    Time Spent In UT  : 0
    Time Spent In LT  : 0
    Time Spent In ST  : 0
    Time Spent In HT  : 0
    Time Spent In OT  : 0
    Time Since Last Charge  : 0
    Threshold  : 600
    Delay  : 2
    Recovery  : 550
    Threshold  : 800
    Delay  : 2
    Recovery  : 650
    Threshold  : 0
    Delay  : 2
    Recovery Threshold  : 50
    Recovery Delay  : 0
    Threshold  : 2
    Delay  : 0
    Recovery Threshold  : 12805
    Recovery Delay  : 2
    Threshold and Delay  : 70
    Latch Limit  : 7
    Counter Dec Delay  : 208
    Recovery  : 7
    Reset  : 8
    Threshold and Delay  : 17
    Latch Limit  : 2
    Counter Dec Delay  : 9
    Recovery  : 196
    Reset  : 7
    Threshold  : -12078
    Delay  : 240
    Recovery  : 2
    Threshold  : 300
    Delay  : 0
    Recovery  : 602
    Threshold  : 0
    Delay  : 0
    Recovery  : 39
    Threshold  : 4101
    Delay  : 216
    Recovery  : -4091
    Charge Threshold  : 650
    Suspend Threshold  : 1283
    Delay  : 59397
    Reset  : 2232
    Charge Threshold  : 10
    Suspend Threshold  : 500
    Delay  : 1280
    Reset  : 25600
    Threshold  : 1285
    Recovery  : -5
    RSOC Recovery  : 5
    Threshold  : 1380
    Delay  : 5
    Threshold  : 5120
    Delay  : 42
    Threshold  : 6232
    Delay  : 0
    Threshold  : 24
    Delay  : 88
    Check Voltage  : -11130
    Check Current  : 19054
    Delta Threshold  : 11011
    Delta Delay  : 124
    Duration  : 328
    OFF Threshold  : -605
    OFF Delay  : 246
    OFF Threshold  : 29970
    OFF Delay  : 88
    Threshold  : 45
    Delay Period  : 183
    Compare Period  : 45
    Threshold  : 183
    Delay Period  : 0
    Threshold  : 0
    Delay Period  : 70
    Delay  : 80
    SOV and SUV Delay  : 06
    Threshold  : -28666
    Threshold  : 200
    Safety Alert A  : 00
    Safety Status A  : 00
    Safety Alert B  : 00
    Safety Status B  : 00
    Safety Alert C  : 00
    Safety Status C  : 00
    PF Alert A  : 00
    PF Status A  : 00
    PF Alert B  : 00
    PF Status B  : 00
    PF Alert C  : 00
    PF Status C  : 00
    Fuse Flag  : 0000
    Operation Status A  : 0000
    Operation Status B  : 0000
    Temp Range  : 00
    Charging Status  : 00
    Gauging Status  : 00
    CEDV Status  : 00
    Cell 1 Voltage  : 0
    Cell 2 Voltage  : 0
    Cell 3 Voltage  : 0
    Cell 4 Voltage  : 0
    Cell 5 Voltage  : 0
    Cell 6 Voltage  : 0
    Cell 7 Voltage  : 0
    Cell 8 Voltage  : 0
    Cell 9 Voltage  : 0
    Cell 10 Voltage  : 0
    Cell 11 Voltage  : 0
    Cell 12 Voltage  : 0
    Cell 13 Voltage  : 0
    Cell 14 Voltage  : 0
    Cell 15 Voltage  : 0
    Battery Direct Voltage  : 0
    Current  : 0
    TS1 Temperature  : 0
    TS2 Temperature  : 0
    TS3 Temperature  : 0
    AFE SYS Stat  : 00
    AFE Cell Balance1  : 00
    AFE Cell Balance2  : 00
    AFE Cell Balance3  : 00
    AFE Sys Control1  : 00
    AFE Sys Control2  : 00
    AFE Protection1  : 00
    AFE Protection2  : 00
    AFE Protection3  : 00
    AFE OV Trip  : 00
    AFE UV Trip  : 00
    1st Status Status A  : 00
    1st Status Status B  : 00
    1st Safety Status C  : 00
    1st Time to Next Event  : 0
    2nd Status Status A  : 00
    2nd Status Status B  : 00
    2nd Safety Status C  : 00
    2nd Time to Next Event  : 0
    3rd Status Status A  : 00
    3rd Status Status B  : 00
    3rd Safety Status C  : 00
    3rd Time to Next Event  : 0
    1st PF Status A  : 00
    1st PF Status B  : 00
    1st PF Status C  : 00
    1st Time to Next Event  : 0
    2nd PF Status A  : 00
    2nd PF Status B  : 00
    2nd PF Status C  : 00
    2nd Time to Next Event  : 0
    3rd PF Status A  : 00
    3rd PF Status B  : 00
    3rd PF Status C  : 00
    3rd Time to Next Event  : 0
    EMF  : 38147
    C0  : 25359
    R0  : 48641
    T0  : 15369
    R1  : 55041
    TC  : 13
    C1  : 57
    Age Factor  : 1
    Fixed EDV 0  : 3501
    EDV 0 Hold Time  : 1
    Fixed EDV 1  : 0
    EDV 1 Hold Time  : 1
    Fixed EDV 2  : 11266
    EDV 2 Hold Time  : 188
    Battery Low %  : 512
    Min Delta V Filter  : 2050
    FCC Learn Up  : 25600
    FCC Learn Down  : 30474
    Learning Low Temp  : 19
    Requested Learning cycle count  : 200
    OverLoad Current  : 0
    Self Discharge Rate  : 100
    Electronics Load  : 4400
    Near Full  : 6336
    Reserve Capacity  : 3600
    Qmax Pack  : -1
    Learned Full Charge Capacity  : -1
    Dod at EDV2  : 4400
    Cycle Count  : 4400
    Dsg Current Threshold  : 1290
    Chg Current Threshold  : 3840
    Quit Current  : 2565
    Dsg Relax Time  : 15
    Chg Relax Time  : 15
    Design Capacity mAh  : 763
    Design Capacity cWh  : 5
    Design Voltage  : 25695
    Cycle Count Percentage  : 6
    Set % RSOC Threshold  : 45
    Clear % RSOC Threshold  : 55
      Set % RSOC Threshold  : 3
    Clear % RSOC Threshold  : 16
    Set % RSOC Threshold  : 104
    Clear % RSOC Threshold  : 11
    Set % RSOC Threshold  : 184
    Clear % RSOC Thresh+E1:E441old  : 0