BQ40Z60EVM-578: Charging with BQ40Z60 does not working

R D2

Part Number: BQ40Z60EVM-578
Other Parts Discussed in Thread: BQ40Z60

Hi there,

Steps that i have done:

choose the chemID 2059 for INR18650MJ1
configure the "Data Memory"
run the "Calibration" – Current Calibration and Voltage Calibration, Temperature Calibration was not done
start a "Learning Cycle"
1. DISCHARGING
  1. when "Learning Cycle" was started -> press GAUGE_EN and RESET at "Commands" view, so that QEN = high/red and RDIS = high/red
  2. start discharging DC load
  3. relaxing after discharging or wait until REST = high/red

I'm performing a learning cycle with a batterypack (2S2P of INR18650MJ1 chemid 2059) and it seems that step 4. a. - DISCHARGING was succesfully (but something strange happens – while Discharging NSFM was high/red in IT Status (low) register).

Now the learning cycle says "Charge Mode - Connect charger now.", so i connect my lab power supply (9V@3,4A) and the message does not changed.

Then i'm looked at the "DashBoard" and see there is no current flowing. The "Registers" view show that the bit ACLW at "Operation Status A" Register is high/red.

After changing the voltage at 9,7V the bit ACLW at "Operation Status A" Register is low/green and the ACFET is high/red, the bit CHGR at "Charger Status" register change from low/green to high/red.

At the "Registers" view i'm observing that the "AC Adapter voltage" is 6149mV.

1. Question: What does NSFM or Negative Ra Scale Factor Mode mean? Was step 4. a. successfully?

2. Question: Why the gauge does not charge the batterypack? Is the data memory not configured properly?

Could someone help me please?

here a screenshot and some data

Data-Memory-Config.gg.csv

RegisterLogFolder.zip

DataMemoryLogFolder.zip

kind regards and thanks

over 5 years ago

0 Dominik Hartl11 over 5 years ago

TI__Guru 61536 points

Your log file shows that Vacp is erratic when you try to charge. The gauge will only allow charging if Vacp > (vBAT + VacpHysteresis). VacpHysteresis is 0mV by default so you must make sure the Vacp > vBAT and that it stays above vBAT.

0 Andy Liu (BMS) over 5 years ago

TI__Guru 52115 points

The learning cycle has two modes, which are Manual Mode or Automation Mode? Have you tried the Manual Mode?

Andy

0 R D2 over 5 years ago in reply to Andy Liu (BMS)

Intellectual 265 points

I'm using the manual mode.

0 R D2 over 5 years ago in reply to Dominik Hartl11

Intellectual 265 points

The erratic voltage is my debt. Should i measure the voltage between VSYS to PGND or between the psu voltage for calibrating the "Applied Pack Voltage"?

When i'm using the voltage displayed on my psu for calibrating the voltage corresponds to the "Registers" view (AC Adapter voltage).

When i'm using the voltage between VSYS to PGND the voltage is different from the psu one.

0 Andy Liu (BMS) over 5 years ago in reply to R D2

TI__Guru 52115 points

See 3.3.1 Voltage Calibration of bq40z60 EVM user's guide. I would suggest you follow the instructions there.

Andy

0 R D2 over 5 years ago in reply to Andy Liu (BMS)

Intellectual 265 points

I followed the instructions of the document SLUUB71, but without any successful result.

thanks for your response

Riccardo

0 R D2 over 5 years ago in reply to R D2

Intellectual 265 points

Which register should be set of the gauge, when the gauge is charging?
Could I start manually a charging cycle?

0 Dominik Hartl11 over 5 years ago in reply to R D2

TI__Guru 61536 points

The gauge indicates with ChargerStatus() CHRG that the charger is enabled. ChargingStatus() gives you clues what is currently happening with the charger.

If the AC FET is on and you apply a voltage that is high enough for charging to ACP/VAC and all conditions for charging (CHG FET is on, all protection parameters are ok) then the bq40z60 will charge the cells. There is no need to manually start this.

0 R D2 over 5 years ago in reply to Dominik Hartl11

Intellectual 265 points

Thank you very much for your answer. This does not solve the problem. I have now loaded an old configuration with different parameters and charging works now, but I can not understand why?

I have specifically changed the values in "Advanced Charge Algorithm" in the subsection "Voltage Range" and "Charger" and set the bit in SOC Flag Config A & B for TC and FC this seems that does the job. But the termination of the charging process seems not to work correctly and the "VCT" bit of the "Charging Status(low)" register is not set. It toggles between charge and charging termination. Is that a normal behaviour?

The datasheet "bq40z60 Programmable Battery Pack Manager Technical Reference Manual Literature Number: SLUUA04D" says that the condition is: All of the following conditions must occur for two consecutive 40-s periods: Charging (that is, BatteryStatus[DSG] = 0) AND AverageCurrent() < Charge Term Taper Current AND Max cell voltage1..4 + Charge Term Voltage ≥ ChargingVoltage() / number of cells in series AND The accumulated change in capacity > 0.25 mAh.

Then there is an other problem that in "Safety Alert C+D(low)" the OC bit is set. Which parameter is responsible for the "OC" bit?

Finally, my working configuration for which it is of interest.

Data-Memory-Config-working.gg.csv

old one:

Data-Memory-Config-old.gg.csv

0 Andy Liu (BMS) over 5 years ago in reply to R D2

TI__Guru 52115 points

The OC means overcharge. See 2.19 Overcharge Protection of the bq40z60 TRM.

Andy

0 R D2 over 5 years ago in reply to Andy Liu (BMS)

Intellectual 265 points

Ok thanks for your replies.

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BQ40Z60EVM-578: Charging with BQ40Z60 does not working