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BQ27520-G4: Learning cycle failing with update status remaining 0 after first full charge

Ross Johnson
Prodigy 230 points
Part Number: BQ27520-G4
Other Parts Discussed in Thread: BQ24192, BQEVSW, BQSTUDIO, GPCRA0

Hello,

I am having difficulty getting the update status to change from 0 to 1 during a learning cycle. I have previously done a successful learning cycle but we have changed cell brand/model to Panasonic NCR18650B (1S4P). The new pack has a design capacity of 12000mAh (previously 8800mAh). Except for the change in battery, all other hardware is unchanged.

The steps I have followed are:-

  1. Reprogram firmware (3.29) to clear any hidden flags (as the gauge has previously been programmed and sealed in production).
  2. Load the new chemistry 2030 (one of several recommended during a chemistry analysis with <2% max error).
  3. Write configuration settings (modified from the previous values for the new chemistry and design capacity) - file attached.
    AX18 Pre-Learn.gg.csv.txt 
    * Texas Instruments Data Flash File
* File created Mon May 08 12:24:02 2017
*
* Device Number 520
* Firmware Version 3.29
* Build Number not available
* Order Number not available
*
* bqz Device Number 0x0520
* bqz Firmware Version 0x0329
* bqz Build Number 3.29
*
* Field Order: Class name, Subclass name, Parameter name, Parameter Value,Display Units
Configuration,Safety,OT Chg,55.0,°C
Configuration,Safety,OT Chg Time,2,s
Configuration,Safety,OT Chg Recovery,50.0,°C
Configuration,Safety,OT Dsg,60.0,°C
Configuration,Safety,OT Dsg Time,2,s
Configuration,Safety,OT Dsg Recovery,55.0,°C
Configuration,Charge Inhibit Cfg,Chg Inhibit Temp Low,0,°C
Configuration,Charge Inhibit Cfg,Chg Inhibit Temp High,45.0,°C
Configuration,Charge Inhibit Cfg,Temp Hys,5.0,°C
Configuration,Charge,Charging Voltage,4200,mV
Configuration,Charge,Delta Temp,5.0,°C
Configuration,Charge,Suspend Low Temp,-5.0,°C
Configuration,Charge,Suspend High Temp,55.0,°C
Configuration,Charge Termination,Taper Current,384,mA
Configuration,Charge Termination,Taper Voltage,100,mV
Configuration,Charge Termination,TCA Set %,99,%
Configuration,Charge Termination,TCA Clear %,95,%
Configuration,Charge Termination,FC Set %,-1,%
Configuration,Charge Termination,FC Clear %,98,%
Configuration,Charge Termination,DODatEOC Delta T,5.0,°C
Configuration,Data,Initial Standby,-10,mA
Configuration,Data,CC Threshold,10800,mAh
Configuration,Data,Design Capacity,12000,mAh
Configuration,Data,Des Energy Scale,10,Num
Configuration,Data,SOH LoadI,-400,mA
Configuration,Data,Default Temperature,298.2,°K
Configuration,Data,Device Name,bq27520,String
Configuration,Data,Data Flash Version,0003,Hex
Configuration,Discharge,SOC1 Set Threshold,600,mAh
Configuration,Discharge,SOC1 Clear Threshold,720,mAh
Configuration,Discharge,SysDown Set Volt Threshold,3150,mV
Configuration,Discharge,SysDown Set Volt Time,2,s
Configuration,Discharge,SysDown Clear Volt,3400,mV
Configuration,Discharge,Final Voltage,3100,mV
Configuration,Discharge,Final Volt Time,2,s
Configuration,Discharge,Def Avg I Last Run,-10,mA
Configuration,Discharge,Def Avg P Last Run,-40,mW
Configuration,Registers,Op Config,0973,Flag
Configuration,Registers,SOC Delta,1,%
Configuration,Registers,i2c Timeout,4,0.5s
Configuration,Registers,DF Wr Ind Wait,0,100us
Configuration,Registers,OpConfig B,4a,Flag
Configuration,Registers,OpConfig C,2c,Flag
Configuration,Registers,OpConfig D,5e,Flag
Configuration,Registers,OpConfig E,00,Flag
Configuration,Power,Flash Update OK Voltage,2800,mV
Configuration,Power,Sleep Current,10,mA
Configuration,Power,Hibernate I,8,mA
Configuration,Power,Hibernate V,2550,mV
System Data,Manufacturer Info,Block 0,00,Hex
System Data,Manufacturer Info,Block 1,00,Hex
System Data,Manufacturer Info,Block 2,00,Hex
System Data,Manufacturer Info,Block 3,00,Hex
System Data,Manufacturer Info,Block 4,00,Hex
System Data,Manufacturer Info,Block 5,00,Hex
System Data,Manufacturer Info,Block 6,00,Hex
System Data,Manufacturer Info,Block 7,00,Hex
System Data,Manufacturer Info,Block 8,00,Hex
System Data,Manufacturer Info,Block 9,00,Hex
System Data,Manufacturer Info,Block 10,00,Hex
System Data,Manufacturer Info,Block 11,00,Hex
System Data,Manufacturer Info,Block 12,00,Hex
System Data,Manufacturer Info,Block 13,00,Hex
System Data,Manufacturer Info,Block 14,00,Hex
System Data,Manufacturer Info,Block 15,00,Hex
System Data,Manufacturer Info,Block 16,00,Hex
System Data,Manufacturer Info,Block 17,00,Hex
System Data,Manufacturer Info,Block 18,00,Hex
System Data,Manufacturer Info,Block 19,00,Hex
System Data,Manufacturer Info,Block 20,00,Hex
System Data,Manufacturer Info,Block 21,00,Hex
System Data,Manufacturer Info,Block 22,00,Hex
System Data,Manufacturer Info,Block 23,00,Hex
System Data,Manufacturer Info,Block 24,00,Hex
System Data,Manufacturer Info,Block 25,00,Hex
System Data,Manufacturer Info,Block 26,00,Hex
System Data,Manufacturer Info,Block 27,00,Hex
System Data,Manufacturer Info,Block 28,00,Hex
System Data,Manufacturer Info,Block 29,00,Hex
System Data,Manufacturer Info,Block 30,00,Hex
System Data,Manufacturer Info,Block 31,00,Hex
Gas Gauging,IT Cfg,Load Select,1,Num
Gas Gauging,IT Cfg,Load Mode,0,Num
Gas Gauging,IT Cfg,Max Res Factor,15,Num
Gas Gauging,IT Cfg,Min Res Factor,7,Num
Gas Gauging,IT Cfg,Ra Filter,800,Num
Gas Gauging,IT Cfg,Fast Qmax Start DOD %,92,%
Gas Gauging,IT Cfg,Fast Qmax End DOD %,96,%
Gas Gauging,IT Cfg,Fast Qm Start V Delta,125,mV
Gas Gauging,IT Cfg,Fast Qmax Current Threshold,4,Hr rate
Gas Gauging,IT Cfg,Fast Qmax Min Points,3,Num
Gas Gauging,IT Cfg,Min % Passed Chg for Qm,37,%
Gas Gauging,IT Cfg,Qmax Filter,96,Num
Gas Gauging,IT Cfg,Max % Default Qmax,110,%
Gas Gauging,IT Cfg,Terminate Voltage,3300,mV
Gas Gauging,IT Cfg,Term V Delta,200,mV
Gas Gauging,IT Cfg,ResRelax Time,500,s
Gas Gauging,IT Cfg,User Rate-mA,0,mA
Gas Gauging,IT Cfg,User Rate-m/cW,0,pwr
Gas Gauging,IT Cfg,Reserve Cap-mAh,600,mAh
Gas Gauging,IT Cfg,Reserve Cap-m/cWh,222,pwr
Gas Gauging,IT Cfg,Min Delta Voltage,0,mV
Gas Gauging,IT Cfg,Max Sim Rate,1,Hr rate
Gas Gauging,IT Cfg,Min Sim Rate,20,Hr rate
Gas Gauging,IT Cfg,Ra Max Delta,44,mOhm
Gas Gauging,IT Cfg,Qmax Max Delta %,5,%
Gas Gauging,IT Cfg,DeltaV Max dV,10,mV
Gas Gauging,IT Cfg,Max Res Scale,5000,Num
Gas Gauging,IT Cfg,Min Res Scale,200,Num
Gas Gauging,IT Cfg,Fast Scale Start SOC,10,%
Gas Gauging,Current Thresholds,Dsg Current Threshold,60,mA
Gas Gauging,Current Thresholds,Chg Current Threshold,75,mA
Gas Gauging,Current Thresholds,Quit Current,40,mA
Gas Gauging,Current Thresholds,Dsg Relax Time,60,s
Gas Gauging,Current Thresholds,Chg Relax Time,60,s
Gas Gauging,Current Thresholds,Quit Relax Time,1,s
Gas Gauging,Current Thresholds,Transient Factor Charge,128,Num
Gas Gauging,Current Thresholds,Transient Factor Discharge,128,Num
Gas Gauging,Current Thresholds,Max IR Correct,400,mV
Gas Gauging,State,IT Enable,00,Hex
Gas Gauging,State,App Status,00,Flag
Gas Gauging,State,Qmax Cell 0,1000,mAh
Gas Gauging,State,Cycle Count 0,0,Num
Gas Gauging,State,Update Status 0,00,Hex
Gas Gauging,State,Qmax Cell 1,1000,mAh
Gas Gauging,State,Cycle Count 1,0,Num
Gas Gauging,State,Update Status 1,00,Hex
Gas Gauging,State,Avg I Last Run,-10,mA
Gas Gauging,State,Avg P Last Run,-4,pwr
Gas Gauging,State,Delta Voltage,2,mV
Gas Gauging,State,T Rise,2,Num
Gas Gauging,State,T Time Constant,1000,Num
Gas Gauging,State,Cell 0 V at Chg Term,4200,mV
Gas Gauging,State,Cell 1 V at Chg Term,4200,mV
OCV Tables,OCVa0 Table,Chem ID,2030,Flag
OCV Tables,OCVa0 Table,Qmax Cell,1000,mAh
OCV Tables,OCVa0 Table,Update Status,00,Hex
OCV Tables,OCVa1 Table,Chem ID,2030,Flag
OCV Tables,OCVa1 Table,Qmax Cell,1000,mAh
OCV Tables,OCVa1 Table,Update Status,00,Hex
Ra Tables,Ra0 Default,Ra Status,ff,Hex
Ra Tables,Ra0 Default,Ra Flag,55,Hex
Ra Tables,Ra0 Default,Ra Base,16,Num
Ra Tables,Ra0 Default,Ra Gain,0,Num
Ra Tables,Ra0 Default,Ra 1,1,Num
Ra Tables,Ra0 Default,Ra 2,4,Num
Ra Tables,Ra0 Default,Ra 3,8,Num
Ra Tables,Ra0 Default,Ra 4,-8,Num
Ra Tables,Ra0 Default,Ra 5,-1,Num
Ra Tables,Ra0 Default,Ra 6,2,Num
Ra Tables,Ra0 Default,Ra 7,-5,Num
Ra Tables,Ra0 Default,Ra 8,0,Num
Ra Tables,Ra0 Default,Ra 9,1,Num
Ra Tables,Ra0 Default,Ra 10,1,Num
Ra Tables,Ra0 Default,Ra 11,6,Num
Ra Tables,Ra0 Default,Ra 12,8,Num
Ra Tables,Ra0 Default,Ra 13,21,Num
Ra Tables,Ra0 Default,Ra 14,10,Num
Ra Tables,Ra1 Default,Ra Status,ff,Hex
Ra Tables,Ra1 Default,Ra Flag,55,Hex
Ra Tables,Ra1 Default,Ra Base,16,Num
Ra Tables,Ra1 Default,Ra Gain,0,Num
Ra Tables,Ra1 Default,Ra 1,1,Num
Ra Tables,Ra1 Default,Ra 2,4,Num
Ra Tables,Ra1 Default,Ra 3,8,Num
Ra Tables,Ra1 Default,Ra 4,-8,Num
Ra Tables,Ra1 Default,Ra 5,-1,Num
Ra Tables,Ra1 Default,Ra 6,2,Num
Ra Tables,Ra1 Default,Ra 7,-5,Num
Ra Tables,Ra1 Default,Ra 8,0,Num
Ra Tables,Ra1 Default,Ra 9,1,Num
Ra Tables,Ra1 Default,Ra 10,1,Num
Ra Tables,Ra1 Default,Ra 11,6,Num
Ra Tables,Ra1 Default,Ra 12,8,Num
Ra Tables,Ra1 Default,Ra 13,21,Num
Ra Tables,Ra1 Default,Ra 14,10,Num
Ra Tables,Ra0 Table,Ra Status,ff,Hex
Ra Tables,Ra0 Table,Ra Flag,55,Hex
Ra Tables,Ra0 Table,Ra Base,16,Num
Ra Tables,Ra0 Table,Ra Gain,0,Num
Ra Tables,Ra0 Table,Ra 1,1,Num
Ra Tables,Ra0 Table,Ra 2,4,Num
Ra Tables,Ra0 Table,Ra 3,8,Num
Ra Tables,Ra0 Table,Ra 4,-8,Num
Ra Tables,Ra0 Table,Ra 5,-1,Num
Ra Tables,Ra0 Table,Ra 6,2,Num
Ra Tables,Ra0 Table,Ra 7,-5,Num
Ra Tables,Ra0 Table,Ra 8,0,Num
Ra Tables,Ra0 Table,Ra 9,1,Num
Ra Tables,Ra0 Table,Ra 10,1,Num
Ra Tables,Ra0 Table,Ra 11,6,Num
Ra Tables,Ra0 Table,Ra 12,8,Num
Ra Tables,Ra0 Table,Ra 13,21,Num
Ra Tables,Ra0 Table,Ra 14,10,Num
Ra Tables,Ra1 Table,Ra Status,ff,Hex
Ra Tables,Ra1 Table,Ra Flag,55,Hex
Ra Tables,Ra1 Table,Ra Base,16,Num
Ra Tables,Ra1 Table,Ra Gain,0,Num
Ra Tables,Ra1 Table,Ra 1,1,Num
Ra Tables,Ra1 Table,Ra 2,4,Num
Ra Tables,Ra1 Table,Ra 3,8,Num
Ra Tables,Ra1 Table,Ra 4,-8,Num
Ra Tables,Ra1 Table,Ra 5,-1,Num
Ra Tables,Ra1 Table,Ra 6,2,Num
Ra Tables,Ra1 Table,Ra 7,-5,Num
Ra Tables,Ra1 Table,Ra 8,0,Num
Ra Tables,Ra1 Table,Ra 9,1,Num
Ra Tables,Ra1 Table,Ra 10,1,Num
Ra Tables,Ra1 Table,Ra 11,6,Num
Ra Tables,Ra1 Table,Ra 12,8,Num
Ra Tables,Ra1 Table,Ra 13,21,Num
Ra Tables,Ra1 Table,Ra 14,10,Num
Ra Tables,Ra0x Table,Ra Status,ff,Hex
Ra Tables,Ra0x Table,Ra Flag,ff,Hex
Ra Tables,Ra0x Table,Ra Base,16,Num
Ra Tables,Ra0x Table,Ra Gain,0,Num
Ra Tables,Ra0x Table,Ra 1,1,Num
Ra Tables,Ra0x Table,Ra 2,4,Num
Ra Tables,Ra0x Table,Ra 3,8,Num
Ra Tables,Ra0x Table,Ra 4,-8,Num
Ra Tables,Ra0x Table,Ra 5,-1,Num
Ra Tables,Ra0x Table,Ra 6,2,Num
Ra Tables,Ra0x Table,Ra 7,-5,Num
Ra Tables,Ra0x Table,Ra 8,0,Num
Ra Tables,Ra0x Table,Ra 9,1,Num
Ra Tables,Ra0x Table,Ra 10,1,Num
Ra Tables,Ra0x Table,Ra 11,6,Num
Ra Tables,Ra0x Table,Ra 12,8,Num
Ra Tables,Ra0x Table,Ra 13,21,Num
Ra Tables,Ra0x Table,Ra 14,10,Num
Ra Tables,Ra1x Table,Ra Status,ff,Hex
Ra Tables,Ra1x Table,Ra Flag,ff,Hex
Ra Tables,Ra1x Table,Ra Base,16,Num
Ra Tables,Ra1x Table,Ra Gain,0,Num
Ra Tables,Ra1x Table,Ra 1,1,Num
Ra Tables,Ra1x Table,Ra 2,4,Num
Ra Tables,Ra1x Table,Ra 3,8,Num
Ra Tables,Ra1x Table,Ra 4,-8,Num
Ra Tables,Ra1x Table,Ra 5,-1,Num
Ra Tables,Ra1x Table,Ra 6,2,Num
Ra Tables,Ra1x Table,Ra 7,-5,Num
Ra Tables,Ra1x Table,Ra 8,0,Num
Ra Tables,Ra1x Table,Ra 9,1,Num
Ra Tables,Ra1x Table,Ra 10,1,Num
Ra Tables,Ra1x Table,Ra 11,6,Num
Ra Tables,Ra1x Table,Ra 12,8,Num
Ra Tables,Ra1x Table,Ra 13,21,Num
Ra Tables,Ra1x Table,Ra 14,10,Num
Calibration,Data,CC Gain,12.166,mOhm
Calibration,Data,CC Delta,12.144,mOhm
Calibration,Data,CC Offset,-1432,Counts
Calibration,Data,Board Offset,11,Counts
Calibration,Data,Int Temp Offset,1.9,°C
Calibration,Data,Ext Temp Offset,1.0,°C
Calibration,Data,Pack V Offset,-22,mV
Calibration,Temp Model,Ext a Coef 1,-11130,Num
Calibration,Temp Model,Ext a Coef 2,19142,Num
Calibration,Temp Model,Ext a Coef 3,-19262,Num
Calibration,Temp Model,Ext a Coef 4,28203,Num
Calibration,Temp Model,Ext a Coef 5,892,Num
Calibration,Temp Model,Ext b Coef 1,328,Num
Calibration,Temp Model,Ext b Coef 2,-605,Num
Calibration,Temp Model,Ext b Coef 3,-2443,Num
Calibration,Temp Model,Ext b Coef 4,4696,Num
Calibration,Temp Model,Ext Ideal AD at Tcal,11703,Num
Calibration,Temp Model,Ext True AD at Tcal,11338,Num
Calibration,Current,Deadband,5,mA
Security,Codes,Sealed to Unsealed,36720414,Hex
Security,Codes,Unsealed to Full,ffffffff,Hex
  4. Run the learning cycle with 2000mA discharge (CC load) and 2050mA charge (BQ24192).


The following log shows the state changes during discharge (to 2900mV) and subsequent full charge (to 4200mA and 256mA taper). A detailed log of the actual voltage/current logs is attached. learn log 1.txt

2017-05-18 12:29:48  Discharge  controlStatus=0294, flags=013C, qmax=1000, updateStatus=0, raUpdates=1
2017-05-18 12:29:51  Discharge  controlStatus=0284, flags=013D, qmax=1000, updateStatus=0, raUpdates=1  (dsg=1)
2017-05-18 16:27:46  Discharge  controlStatus=0284, flags=013F, qmax=1000, updateStatus=0, raUpdates=1  (sysdown=1)
2017-05-18 17:54:21  Relax      controlStatus=0284, flags=013F, qmax=1000, updateStatus=0, raUpdates=1
2017-05-18 17:55:26  Relax      controlStatus=0294, flags=013E, qmax=1000, updateStatus=0, raUpdates=1  (dsg=0)
2017-05-18 17:56:26  Relax      controlStatus=0A84, flags=013E, qmax=1000, updateStatus=0, raUpdates=1  (cca=1)
2017-05-18 17:56:41  Relax      controlStatus=0294, flags=013E, qmax=1000, updateStatus=0, raUpdates=1    (cca=0)
2017-05-18 18:55:31  Relax      controlStatus=0A84, flags=013E, qmax=1000, updateStatus=0, raUpdates=1  (cca=1)
2017-05-18 18:55:46  Relax      controlStatus=0284, flags=013E, qmax=1000, updateStatus=0, raUpdates=1  (cca=0)
2017-05-18 19:54:21  Relax      controlStatus=0294, flags=013E, qmax=1000, updateStatus=0, raUpdates=1  (IT ENABLED)
2017-05-18 19:54:26  Relax      controlStatus=0293, flags=013E, qmax=1000, updateStatus=0, raUpdates=1  (qen=1, vok=1, rup_dis=0)
2017-05-18 20:00:51  Charge     controlStatus=0291, flags=013E, qmax=1000, updateStatus=0, raUpdates=1  (vok=0)
2017-05-18 20:00:58  Charge     controlStatus=0283, flags=013C, qmax=1000, updateStatus=0, raUpdates=1  (vok=1, sysdown=0)
2017-05-18 20:22:00  Charge     controlStatus=0283, flags=0138, qmax=1000, updateStatus=0, raUpdates=1  (soc1=0)
2017-05-18 20:27:29  Charge     controlStatus=0283, flags=0038, qmax=1000, updateStatus=0, raUpdates=1  (chg=0)
2017-05-19 03:48:20  Charge     controlStatus=0283, flags=0238, qmax=1000, updateStatus=0, raUpdates=1  (fc=1)
2017-05-19 04:08:37  Relax      controlStatus=0283, flags=0238, qmax=1000, updateStatus=0, raUpdates=1
2017-05-19 04:09:39  Relax      controlStatus=0A83, flags=0238, qmax=1000, updateStatus=0, raUpdates=1  (cca=1)
2017-05-19 04:09:59  Relax      controlStatus=0293, flags=0238, qmax=1000, updateStatus=0, raUpdates=1  (cca=0)
2017-05-19 04:46:59  Relax      controlStatus=0291, flags=0238, qmax=1000, updateStatus=0, raUpdates=1  (vok=0)
2017-05-19 05:08:54  Relax      controlStatus=0291, flags=0138, qmax=1000, updateStatus=0, raUpdates=1  (chg=1, fc=0)

A few observations...

  1. The charger (bq24192) actually stopped at a taper current of 323mA (256+27%) which is higher than the maximum in the datasheet but all our units behave that way although I don't know why. The taper current was still low enough for the gauge to register end of charge and set fc.

  2. Integrating the current passed during charge yields a figure of almost 98% of design capacity 11725mAh. I've read in a post that there is a 90% threshold that must be met during the learning cycle (which it is).

  3. The SOC reported by the gauge rises from 0 to 100% during charge in about 20min, presumably because the qmax is incorrect (default).


Following through the 'Achieving The Successful Learning Cycle' application report, I am at a loss to explain what is going wrong. Any help would be greatly appreciated.

Cheers, Ross

  • 0
    TI__Intellectual 1735 points
    Hi,
    Have you sent a IT enable command to the gauge before starting the learning cycle?
    If you have a default unused 27520 in hand, you can export a gg file from the devive and compare with the gauge that you have programmed the 3.29 version firmware. If there is some differences between them, that may cause the problem.
  • 0 in reply to answer
    Prodigy 230 points
    Hi Terry,

    Yes I issued the IT enable command at the timestamp 2017-05-18 19:54:21 above (marked IT ENABLED). The qen=1, vok=1 and rup_dis=0 flag changes wouldn't have occurred otherwise.

    Unfortunatly I don't have any brand new bq27520-G4s to try, as I'm retrofitting a new/better battery into existing units and we have no immediate plans to run a new production run. However, I did reprogram the 3.29 firmware from the downloaded .senc file using bqEVSW. My understanding is that there are some hidden flags which aren't directly reachable by bqStudio that a complete firmware refresh does clear.

    /Ross
  • 0 in reply to Ross Johnson
    TI__Guru* 76230 points
    Ross,
    Your understanding is correct. Programming the firmware wipes the device clean as though it is brand new.

    If your learning is failing, i wouldn't suggest you struggle figuring out why. Simply use our online tool gpcRa0

    www.ti.com/.../GPCRA0


    This will help you calculate qmax and Ra tables and provide you with a gg file to program on the gauge.


    If you are bent on doing the learing cycle, then make sure to charge the battery to the max cell voltage and discharge down to the min voltage stated in the manufacturer data sheet.

    Ensure you have the right rest times as well.

    thanks
    Onyx
  • 0 in reply to Onyx Ahiakwo
    Prodigy 230 points

    Hi Onyx,

    Thanks for the response. I'll look into the GPCRA0 tool.

    Since my original post, I have been able to run a successful learning cycle, but with a different chem id.

    I am using genuine Panasonic NCR18650B cells. The chemistry analysis resulted in 9 possibilities within a 3% error; 2018 (1.6%), 202 (1.64%), 2030 (2%), ... I opted for 2030 as this is the first choice which actually matched my cell by manufacturer and name/model. I made 4 learning cycle attempts (trying various tweak in the config), all of which failed, as described earlier. I changed the chemistry to 2018 (best match) and the learning cycle was successful.

    The previous cell type we were using had a best chem match of over 5%, but I never had trouble running a learning cycle. Is it possible that there is a problem with the chem id 2030 data?

    There was one additional change that I made as well as changing chem id. I changed the 'Configuration/Data/Data Flash Version' from 3 to 0. Previously I had left setting this parameter until preparing the golden image. I assume it has no impact on the learning cycle?

    Regarding your questions... The learning cycle I run consists of; RESET, discharge to 2900mV, wait 2 hours, IT ENABLED, wait for first OCV reading (vok=1->0), charge to 4200mV with 323mA (80mA/cell) taper, observe fc=0->1, wait for second OCV reading (vok=1->0). At this point Qmax remains unchanged and update status is still 0 (even after 12 hours from end of charge).

    The charge rate used is around 2050mA (0.16C). Is this too low? I can possibly get 3A (0.23C) if that would help but the charger (bq24192) jumps significantly in temperature above 2A.

    One final question... After preparing the golden image, I wrote it to the guage and issued RESET, IT ENABLED and SEALED commands. I subsequently realised I needed it unsealed (as my firmware accesses some parameters that are restricted). So I issued RESET, UNSEAL and IT ENABLED commands before running a test cycle. Would any of these commands (especially RESET) impact any of the data loaded from the golden image?

    Regards, Ross

  • 0 in reply to Ross Johnson
    TI__Guru* 76230 points
    HI Ross,
    Sorry for the delay. A reset doesn't change df paramaters. It just reinitializes the RAM of the gauge. it doesn't afftect your golden file programmed on the gauge.

    Since you got successful learning with the best match the tool returned which is 2018, use that. Cell manufacturers tend to change their manufacturing processes and that could affect the electrical properties of the battery. That change of df version is of no consequence. Doesn't affect anything.


    thanks
    Onyx
  • 0 in reply to Onyx Ahiakwo
    Prodigy 230 points
    Thanks Onyx for your assistance.
    /Ross