BQ4050: VCT does not get set when the criteria is met in section 4.6 of sluuaq3.

Hi Cliff,

We will take a look and get back to you.

Andy

Hi Cliff,

Our device expert on this device is on vacation, I can comment based on my limited experience with this device.

Can you export more parameters in your log file?  It is best to simply export everything, then you have all data that may be useful.  For example, you exported Current() here, but not AverageCurrent(), which will be a little different.  It would also be good to see what the gauge reports for ChargingVoltage() throughout the log.

While I am not certain about this device, I recall another device had a typo in the documentation about the accumulated passed charge threshold.  Rather than 0.25mAh it was instead actually 25mAh.  So while doing another log, you might run it long enough to ensure that capacity has also passed after the other conditions are met.

Thanks,

Terry

Hi Terry,

I'll start another log which has everything and post it to this thread.  I'll also increase the Charge Term Taper Current to make sure it's not the accumulated energy.

Thanks,

Cliff

Here is the full log of every register during a charge from completely dead until the current goes below the 250mA threshold.  I stopped the log when it reached 180mA which was 11 minutes after the 150mA threshold and 19mAh of energy accumulation.  For some reason, the "Remaining Capacity" register sopped counting at 4058 even though the charging current wasn't at 0mA.  The "CEDV RC" register still increased until the logging stopped though.  

I'm trying to get the "ChargingStatus" register to enable the VCT bit and change the "Remaining Capacity" register to equal the "Full Charge Capacity" register (4100mAh) but the "ChargingStatus" register stays at 0x8008.  

5153.Full log for TI.log.xlsx

This thread says "TI thinks resolved" so I just wanted to make sure my responses below did not accidentally flag this thread as being resolved.  My setup will still not set the VCT flag.

Thanks,

Cliff

Hi Kang,

All of the VCT conditions were met at 12/30/2019  5:28:26 AM and I stopped the log at 12/30/2019  5:39:46 AM.  

Here are is the GG file from the gas gauge used to create the log.

Thanks,

Cliff1_10_2020.gg.csv

Hello Cliff,

Are you sure you attached the right gg.csv file?

Can you send me the gg.csv file after you ran the test?

Also, could you run the following

1. Log with bqStudio a relaxed portion of the pack with no current

2. Start charging.

3. Go to taper conditions

I would like to see a repeat test with a known gg.csv file at the beginning of step 1 and end of step 3.

Hi Kang,

Here is the information you requested.  The "1_17_charge for TI.xlsx" log contains 14 minutes of relaxed time before the charging started.  The "1_17_relaxed.gg.csv" GG file was taken before the charging started and the "1_17 after charge for TI.gg.csv" was taken after the charging stopped.  

This log also shows the other issue I'm seeing with this setup.  The "Remaining Capacity" register gets stuck at 4058mAh and doesn't increase even though there is current going to the batteries.  The CEDV RC register keeps counting though.  I'm not sure if these two issues are related.

Thanks in advanced for your help.

Cliff

1_17 after charge for TI.gg.csv

1_17_charge for TI.xlsx

1_17_charge for TI.log

Hi Kang,

I do not believe the GAUGE_EN bit can be read from the ManufacturerAccess() 0x0057 ManufacturingStatus register.  This is the register which is stored in the log I provided.  In section 13.1.39 of sluuaq3, the bit descriptions of this register does not have GAUGE_EN.  I believe it would be bit 3 but this bit is RSVD.  

I do have GAUGE_EN set in the Manufacturing Status Init register (Section 14.3.1) although this bit shows up as RSVD in the TI Battery Management Studio when you select the BQ4050.  I'm not sure if this is a bug with the BMS or if the BQ4050 really doesn't have this GAUGE_EN bit.  There isn't a command to set it described in the sluuaq3.

On another note, it seems like the CEDV RC register is more accurate at measuring the capacity but the RSOC doesn't use this register.  What is this register used for?

Thanks,

Cliff