BQ27Z561-R2: Learning Cycle - Failure at update status 0x05

RDIS will be set during a discharge, if the chemistry isn't compatible or if Qmax is inaccurate. Please make sure that the chemistry is compatible. Even if the chemistry is compatible in principle, sometimes it doesn't cover your charging voltage so you may have to charge to a slightly lower voltage so that Depth Of Discharge(charging voltage, taper current, temperature) or DOD0(OCV, T) doesn't saturate at 0.0.

How can I verify my chemistry id is compatible? 

Yes, the updated qmax(424) is larger than the design capacity (385).  So, how can I overcome this issue? 

How did you obtain your ChemID?

By chemistry Id cycle 

Sharing the log files below

https://drive.google.com/drive/folders/17ABAXQcR8nLIDgV1Joys4UrfujvAxfK5

Please try charging at a lower voltage as a first test if this fixes the RDIS problem. This ChemID tops out at 4400mV and you charge a bit higher (4426mV@63mA). Please set your CV to 4400mV, not 4426mV.

How can I stop the charging at 4400V?

If possible, this would have to be configured with your charger. If your charger doesn't support this, you can, for a test, use a typical lab supply where you set the voltage to 4400mV and the current limiter to the constant charging current. The lab supply will then use a typical constant current followed by constant voltage charging sequence. Turn off the lab supply when the current, during the latter constant voltage phase, drops below taper current (e.g. C/10). If this resolves the RDIS error, then the cause is that the ChemID doesn't cover your 4426mV constant voltage charging setup.

Okay

So I am starting new learning cycle using this method with new chem-id derived from the Chem-id cycle.

Hello Dominik,

I have tried the learning cycle with the Chem Id cycle with the direct external supply. But I found that the charging is taking more time than using the charger module. I am sharing the logs of chem Id cycle with you, where at the C/2 charging rate battery has taken 2 and half hour to full charge. 

The External supply was set at 4.35V and 192 mA current ( as battery datasheet claims).

Chem_id_23_03_1.zip

Chem_id_23_03_1-report.zip

The chem report has the >10 deviation. 

One more thing I noticed is that the voltage that appears on the BQ studio differs by 50mA. While I calibrated the bq27z561, the difference has not gone. I'm also experiencing the noise in current of 3 and -3 mA. which also not gone by calibrating. 

Also sharing the battery datasheet with you. 

8737.GRP333736-3.8V-385mAh.pdf

Please elaborate on the 50mA difference. The log file shows 0mA in relax so I interpret the 50mA as a gain error, hence it should scale with the current. Is it the same scaling factor, regardless of current?

The log file shows behavior that is not consistent with how a cell normally behaves. Cell voltage increases immediately when the -43mA load is turned on, from 4281mV to 4316mV. Therefore the data looks suspicious(and this is likely the reason why GPC can't find a good ChemID match).

Sorry That is 50 mV, and calibrating the voltage did not eliminate that difference.  

Also There is 3 and -3 mA current noise at the time of the relaxed state. That noise appear in the charging and discharging cycle too.

Yes, Can you tell me the reason behind that? 

I have charged the battery directly using the external power supply at the C/2 rate and 4.35V. But in this charging takes two and half hour to reach the taper current and taper voltage.

Hello Jainam,

Are you using  a TI EVM or a custom board?

Hello,

No, I am using the Bq27z561evm board.  

That is strange. Physically disconnect everything and then connect a power supply to the batt terminals. Then log data through EV2400/bqStudio and see if you see the 3mA current reading. That should not happen.

Hello Shirish,

Sorry for the late reply. 

I have done setup as you suggested. But still getting the 3 and -3mA current reading. I am sharing the logs with you using the power supply at battery terminals.

Power_supply_30_0.log

Hello Jainam,

The log does not match a power supply. Make sure to disconnect the battery when using a power supply. The power supply must also be able to supply/sink any current that will flow.