BQ40Z50EVM-561: Problem with updating FC flag in BQstudio

Neelakshi Talukdar

Part Number: BQ40Z50EVM-561
Other Parts Discussed in Thread: EV2400,

Tool/software:

I have a BQ40Z50EVM-561 board and a EV2400 Controller. I have made the connections as per manual and connected a fully charged 3S battery. The charge has been done externally with a battery charger which shows full charge. When I reconnect this battery pack to my BMS setup I'd expect the FC flag to be set. But it still shows green. I have done the battery calliberation correctly as well by setting the measured cell voltage and pack voltage. I am not able to caliberate the bms as I am not able to complete a battery cycle as the software doesn't detect a full charge. Can you please help me with something that I am probably missing out?
PS - New to BMS circuits.
Thanks!

3 months ago

0 Alan Frias 3 months ago

TI__Mastermind 26045 points

Hello Neelakshi,

Typical we recommend charge or discharge the cells with the battery gauge connected to it the entire time. If you perform a discharge and relax cycle the the SOC will update as-well. Please connect the charger to the EVM when charging the system and follow the EVM for brining up the battery gauge.

EVM:
https://www.ti.com/lit/ug/sluuav7c/sluuav7c.pdf?ts=1747673597752&ref_url=https%253A%252F%252Fwww.ti.com%252Ftool%252FBQ40Z50EVM-561

Thank you,
Alan

0 Neelakshi Talukdar 3 months ago in reply to Alan Frias

Prodigy 10 points

Hi, as instructed, I did the necessary connections and tried to charge my battery pack. Now, the pack pin voltage goes upto the full charge capacity. The Batt Voltage also goes upto the full charge capacity. The charger indicates full charge, but the FC flag in the software is still not set. On removing the charger, the voltage drops. I am not able to identify where I am going wrong?
While the battery is charging theirs a certain current consumption as well. and as the charger is removed, the current goes back to 0 and the voltage drops

0 Alan Frias 3 months ago in reply to Neelakshi Talukdar

TI__Mastermind 26045 points

Hello Neelaskshi,

It seems that you haven't done the proper steps to set up your battery gauge and I would recommend following the steps in order.

-Perform calibration
https://www.ti.com/lit/an/slua734a/slua734a.pdf?ts=1748961661656&ref_url=https%253A%252F%252Fwww.ti.com%252Fproduct%252FBQ40Z50

-Update Data memory parameters
Critical Parameters:Design Capacity, Design Voltage, Charge Term Taper Current, Discharge (Dsg) Current Threshold, Charge (Chg) Current Threshold, Quit Current and Term Voltage

-Get correct chemID
https://www.ti.com/tool/GPCCHEM

-Perform a learning cycle
https://www.ti.com/lit/an/slua903/slua903.pdf?ts=1748961567313&ref_url=https%253A%252F%252Fwww.ti.com%252Fproduct%252FBQ40Z50

Thank you,
Alan

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BQ40Z50EVM-561: Problem with updating FC flag in BQstudio