BQ28Z610: Qmax did not appear

Roland Melad

Intellectual 1185 points

Part Number: BQ28Z610
Other Parts Discussed in Thread: GPCCHEM,

Hi,

We have a customer who has concern below:

They have done charging lesson, but at the end, Qmax did not appear.

① BAT discharge in initial nominal state

② Relax over 5h

③ BAT full charge

④ FC(Full Charge)/TC(Terminate Charge) rises, charging is automatically cut off

⑤ After 2h of Relax, the Qmax flag does not appear, and the Update Status does not change from 0x04 → 0x05.

⑥ Qmax flag does not appear even if left over 10h overnight

- Looking at the LOG, [MaxErr] of the BattStatus register is changed from 100 → 3 (this is only updated Qmax),

- But actually, the Qmax flag and Update Status values do not change.

Please check the attached file for the settings and logs.[EXTERNAL] CS0310659 - BQ_Studio_Setting.zip

over 4 years ago

0 Wyatt Keller over 4 years ago

TI__Guru** 105760 points

Hello Roland,

The first step before the learning cycle is to program the matching chemistry ID, otherwise the learning cycle will most likely fail.

We use the GPCCHEM tool and a relax-discharge-relax log to find a good match for the battery.

Sincerely,

Wyatt Keller

0 Yongki Jeong over 4 years ago in reply to Wyatt Keller

Prodigy 100 points

Hi Keller

Thank you for your active help.

Please understand that I am not good at English.
BQ studio and firmware were all updated.
Before asking the question, I did a lot of search for related keywords and tried several tests, but couldn't find a clear cause.
For a question that is weird or difficult to answer, be sure to add an answer such as "I can't understand the question" or "I need to find out more".

201109_Pack.zip

1.BAT: 2S1P

2. BAT Spec: INR21700-50E
1) Standard discharge Capacity: 4900mAh
2) Charging Voltage: 4.2V
3) Nominal Voltage: 3.63V

3. Design plan
1) Full charge voltage: 8320mV / 4160mV per cell
2) 0% discharge voltage: 6600mV / 3300mV per cell
this is not protection value

4. How to proceed
1) Chem ID setting
2) Perform calibration
3) Change multiple parameter values (refer to attached GG file)
4) Start the cycle by referring to the TRM below
-How to Complete a Successful Learning Cycle for the BQ28Z610_(slua777)

5. Question
1) Where is the 'Sense Resistor' setting?
- EVM B/D's sensing resistance is 1mΩ, but BB uses 2mΩ (Range 1~3mΩ)

2) All the register voltages monitored in real time are wrong: Voltage / vBAT / vPACK. (Voltage = CellVol1 + CellVol2)
- Can I ignore the difference between vBAT and vPACK voltage? Should I correct it separately?
- Which voltage should be monitored by major?

4) When learning, is it correct to set so that Protection is not applied?
- Even if VCT or EDV flag is set If protection is activated, does it affect the learning cycle?

5) Is it correct to set the Gauging range tighter than the BAT Voltage Protection range?
Or can I set it narrower?

6) When learning Cycle BAT, what is range of BAT Voltage?
- BAT 2s1p : 6V- 8.4V
- Need Range : 6.6V - 8.36V (for BAT safety)

7) Is it possible to change only the Protection setting after creating the Golden image?

8) Relax 2h after charging: Qmax cannot be toggled. No Update Status 0x05 (maintain 0x04)
- Other Flags are changed normally (FC, REST = 1 / VOK, RDIS = 0)
- When Qmax update occurs, [Qmax] Flag toggles afterwards.
- What does “Toggle” mean? (Blinking / Off→On / On→Off ??)
- If it is not Update Status 0x05, what is the problem? (Maintaining status 0x04)
- Can I discharge with Update Status 0x04? (Originally, it is changed to 0x06 after discharge is completed)

9) During charging, if the charging current is lower than the taper current, is it correct that charging is complete?
- Are these flags only for checking on the CPU? FC, TC, FD, TD
- If the Current() is lower than the Tape Current for tens of seconds, does the charge complete?

10) When charging, when crossing the CC → CV section
- Should I go to CV near the charging voltage? Or is it correct to proceed as shown in the graph below?
- In Setting, what value does the CV section go to? (enter the CV section too quickly)

11) Are there any additional details or explanations for Valid Charge Termination?
- Setting guides, etc. necessary for effective charging termination

12) When discharging, RSOC suddenly changes from 11% to 0%
- Did the ‘FD/TD’ flag occur and the RSOC (RelativeStateOfCharge) suddenly became 0%?
- Is the ‘FD/TD’ flag generated because the RSOC suddenly became 0%?
- Why did RSOC suddenly change from 11% to 0%?

13) The problem is that even if the EDV floats, the discharge continues. Accordingly, after the user intervenes, the discharge rod is forcibly cut off.
- When discharge is complete, does the fuel gauge automatically shut down after detection? Should users be involved?
- If the EDV (End-of-Discharge Termination Voltage) flag is displayed, can the user stop the load? Or is it correct to ignore the EDV and apply UVP (Under Voltage Protection) to the load and cut it off?

- When performing TEST, when EDV appears, BATT Status is changed: 0x00C0 → 0x08D0 (TDA: Terminate Discharge Alarm), Does the TDA alarm affect the learning cycle?

14) When charging/discharging, what are the Flag and Registor values that should be observed?

I am very, very sorry for the many questions. However, even though I searched a lot of data and tried the test, it didn't proceed and I wasted only time.

We ask for your patience, and I hope this forum will help many people.

Thanks

Jeong

0 Wyatt Keller over 4 years ago in reply to Yongki Jeong

TI__Guru** 105760 points

1) Where is the 'Sense Resistor' setting?
- EVM B/D's sensing resistance is 1mΩ, but BB uses 2mΩ (Range 1~3mΩ)

During the current calibration process this will be set, there's no option to set the sense resistor value.

Not sure what is meant by they're all wrong, the gauge updates every 1 second and should be correct at the time of measurement if the gauge is calibrated.

4) When learning, is it correct to set so that Protection is not applied?
- Even if VCT or EDV flag is set If protection is activated, does it affect the learning cycle?

Leave the protections disabled for the learning cycle so the learning process isn't interrupted.

5) Is it correct to set the Gauging range tighter than the BAT Voltage Protection range?
Or can I set it narrower?

You must set the protections depending on your applications needs.

6) When learning Cycle BAT, what is range of BAT Voltage?
- BAT 2s1p : 6V- 8.4V
- Need Range : 6.6V - 8.36V (for BAT safety)

The learning cycle and relax-discharge-relax should be to the same voltage, the voltage specified in the battery manufacturer, you can reduce it to your application later.

7) Is it possible to change only the Protection setting after creating the Golden image?

Yes

You are most likely not meeting on of the criteria defined in SLUA903

All of this is in the TRM, the charge term taper current will signal a full charge to the gauge.

The constant voltage should be set to the battery manufacturers specifications.

11) Are there any additional details or explanations for Valid Charge Termination?
- Setting guides, etc. necessary for effective charging termination

The VCT operation is explained in the TRM.

There's not accurate gauging until the chem ID and learning cycle is complete.

- When performing TEST, when EDV appears, BATT Status is changed: 0x00C0 → 0x08D0 (TDA: Terminate Discharge Alarm), Does the TDA alarm affect the learning cycle?

The protections should be turned off during the learning cycle so they don't interfere.

14) When charging/discharging, what are the Flag and Registor values that should be observed?

The flags you should watch are described in SLUA903, RDIS, VOK, REST, and QMAX are some important flags.

Sincerely,

Wyatt Keller

0 lim sehoon over 4 years ago in reply to Wyatt Keller

Prodigy 80 points

Hello, TI.

I'm Sehun in Bluebird HW Engineer.

Upload the BQ-Studio Setting and LOG files.

- Refer attachment.

Please check why the 'update status' does not change to 0x05 after charging is complete.

(It keeps the update state 0x04.)

Thank you.

Setting&LOG_201104.zip

0 Nick Brylski over 4 years ago in reply to lim sehoon

TI__Mastermind 19195 points

Hi,

You can search our forum for "bq28z610 update status = 0x05", many other have had this same issue.

Best regards,

0 Dexter Choi over 4 years ago in reply to Nick Brylski

Expert 2795 points

Hi Nick,

We found below link and We will test manually change it for 'update status' does not change to 0x05 after charging is complete' issue.

Could you please review Setting & Log file.

1376.Setting&LOG_201104.zip

0 Wyatt Keller over 4 years ago in reply to Dexter Choi

TI__Guru** 105760 points

Hello Dexter and Lim,

The log you shared is not getting a 90% in DOD (It looks to be around 80%) This may be from a bad chem ID or you are not charging and discharging the battery according the battery specifications.

Sincerely,

Wyatt Keller