BQ40Z50-R2: Cell Balancing Cannot Be Enabled

Aji Santoso89

Part Number: BQ40Z50-R2
Other Parts Discussed in Thread: BQ40Z50

Hi,

I want to ask some question about Internal Cell Balancing problems.

Is there any something wrong with calculation or the settings ? I use Lithium Polymer Battery 3S Configuration and have already calculated the cell balancing time based on commands manual.

Here i attach file gg.csv file in ZIP format

Thank you

Best Regards

Aji

11 March 2020_config BATT PACK EXISTING 13.24.gg.zip

over 5 years ago

0 Aji Santoso89 over 5 years ago

Prodigy 230 points

0 Steven Yao over 5 years ago in reply to Aji Santoso89

TI__Genius 12215 points

Aji

There should be no issue for the balance setting parameters, for the balance time, it is calculated by using the cell voltage to be divided by the resistance of resistors and FET in series in each closed loop circuit for cell voltage monitoring

0 Aji Santoso89 over 5 years ago in reply to Steven Yao

Prodigy 230 points

Hi Steven

Do you mean FET in series is internal or with external balancing circuit? and also follow this equation (based on bq40z50 commands manual)?

Does it mean the balancing time calculated automatically or else?

Regards

Aji

0 Steven Yao over 5 years ago in reply to Aji Santoso89

TI__Genius 12215 points

Hi， Aji

The Rcb in above equations refers to internal FET resistance, if you use external cell balancing, you need to calculate Rext, with the example diagram as attached, Rext for the top closed balancing loop is R2+Rds(U1), the balancing time is always calculated manually.

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BQ40Z50-R2: Cell Balancing Cannot Be Enabled