BQ4050: inconsistent readout of battery capacity

Hello Tyler, 

We have assigned this trend and will reach out with a solution when possible.

Thank you,
Alan

Hello Tyler,

I would recommend using the EVM user guide to help you setup the battery gauge  but I would began by running a calibration of the different units in the calibration tab. Afterwards I would update the critical parameters within the data memory table. I would then run the GPCCHEM calculator and get a chemID that has a difference error of 3%. With the BQStudio I would rerun the learning cycle and you shouldn't see any issues on your end. 

EVM User Guide:
https://www.ti.com/lit/ug/sluubf9/sluubf9.pdf?ts=1743109008042&ref_url=https%253A%252F%252Fwww.ti.com%252Fproduct%252FBQ4050

Critical Parameters: 
Design Capacity, Design Voltage, Charge Term Taper Current, Discharge (Dsg) Current Threshold, Charge (Chg) Current Threshold, Quit Current and Term Voltage

GPCCHEM:
https://www.ti.com/tool/GPCCHEM

Learning cycle: 
https://www.ti.com/lit/an/slua903/slua903.pdf?ts=1741893409900&ref_url=https%253A%252F%252Fwww.ti.com%252Fsitesearch%252Fen-us%252Fdocs%252Funiversalsearch.tsp%253FlangPref%253Den-US%2526nr%253D85%2526searchTerm%253DHow+to+achieve+a+success+learning+cycle

Thank you,
Alan 

Hi Alan,

 Thanks for the reply. Just a few questions,

1. For BQ4050, should it be a single cell or a whole pack(for my case 2cells in series) paramters for these registers like Design Capacity, Design Voltage... etc?

2. Regarding the document for battery learning cycle, some question below, 

    in section 3.2.1, how to enable and disable the IT? RDIS bit seems also missing in reference manual of BQ4050.

    in section 3.2.7, seems no golden image tab in bqStudio. What shall I do in order to extract a golden image?

  Do we some document for guiding the learning cycle particularly of BQ4050? 

Best Regards,

Tyler

On more question Alan,

the document also says to "Program the ChemID that matches the cell to be used in the application", the cell I use is panasonic MCR21700T, could I have the ChemID file and could I know how to program the ChemID file into BQ4050? Thanks in advance.

Best Regards,

Tyler

Hello Tyler,

You could possibility find a chemID labeled Panasonic MCR21700T within the chemID library, however due to changes coming from suppliers it is still best practice  to use the GPCCHEM tool.

GPCCHEM:
https://www.ti.com/tool/GPCCHEM

Thank you,
Alan

Hi Alan,

Could you please advise where the chemID library could be accessed? The version of bqStudio I am using is 1.3.127.

Could I have answers to the these questions below?

1. For BQ4050, should it be a single cell or a whole pack(for my case 2 cells in series) paramters for these registers like Design Capacity, Design Voltage... etc?

2. Regarding the document(SLUA903) for battery learning cycle, some question below, 

    in section 3.2.1, how to enable and disable the IT? RDIS bit seems also missing in reference manual of BQ4050.

    in section 3.2.7, seems no golden image tab in bqStudio. What shall I do in order to extract a golden image?

    Is there some specific document for guiding the learning cycle of BQ4050? 

Best Regards,

Tyler Jia

Hello Tyler,

-Could you please advise where the chemID library could be accessed? The version of bqStudio I am using is 1.3.127.

I miss spoke on this product and thought it was a new gauge but since this is a CEDV you would have to follow these steps below..

GPC:
https://www.ti.com/lit/ug/sluub45b/sluub45b.pdf?ts=1743544464559&ref_url=https%253A%252F%252Fwww.ti.com%252Fproduct%252FBQ4050

-1. For BQ4050, should it be a single cell or a whole pack(for my case 2 cells in series) paramters for these registers like Design Capacity, Design Voltage... etc?

The design capacity and design voltage is based on cells in series, use the picture below for reference 

-2. Regarding the document(SLUA903) for battery learning cycle, some question below, 

    in section 3.2.1, how to enable and disable the IT? RDIS bit seems also missing in reference manual of BQ4050.

-Will get back to you 

    in section 3.2.7, seems no golden image tab in bqStudio. What shall I do in order to extract a golden image?

Review this e2e for help
https://e2e.ti.com/support/power-management-group/power-management/f/power-management-forum/1063428/bq4050-golden-file-format-confusion

    Is there some specific document for guiding the learning cycle of BQ4050? 

-Review this e2e for help
 https://e2e.ti.com/support/power-management-group/power-management/f/power-management-forum/1064246/bq4050-set-up-calibration-and-production