BQ78350-R1 : Use of ChemID in gauging apart from Initial Battery Capacity

Mugilan Aravazhi

Other Parts Discussed in Thread: BQ78350-R1

The TRM of bq78350-R1 mentions the use of Chem ID to estimate Initial Battery Capacity at Device Reset.

Is Chem ID also used in CEDV / Impedance track features of the host ? If so which are the parameters/registers affected with a change in Chem ID ?

Does the Host use Max Cell voltage or Min Cell Voltage or the ExtAvgCell Voltage for estimating the RemCap ?

Currently using Chemistry database Version 528

and host FW v1.03 build 22

over 8 years ago

0 ThomasCosby over 8 years ago

TI__Guru 73830 points

The bq78350-R1 uses the OCV from the ChemID to estimate the initial RemCap after a reset. The other parts of the ChemID are not used by the gauge at any time.

The gauge does not use Max Cell voltage or Min Cell Voltage or the ExtAvgCell Voltage for estimating the RemCap.

0 Mugilan Aravazhi over 8 years ago in reply to ThomasCosby

Prodigy 125 points

Thanks for clearing the usage of ChemID in gauge.
I am still not clear on how the initial RemCap is estimated without using Cell voltage data.

As I understood form the TRM 9.1.5 "When assessing the RC vs. OCV correlation, the bq78350-R1 uses the applicable CellVoltage1..15() data
even if ExtAveCellVoltage() data is available."

Out of CellVoltage1..15() data, is the Min/Max/Avg used for the RC vs OCV correlation?

Please correct me if I have understood this incorrectly.

0 ThomasCosby over 8 years ago in reply to Mugilan Aravazhi

TI__Guru 73830 points

The bq78350-R1 will use the cell voltages reported by the bq769xx device and compare them to the OCV table to estimate the RM. It will use the lowest cell voltage for the calculation.

0 Mugilan Aravazhi over 8 years ago in reply to ThomasCosby

Prodigy 125 points

Hi ,
Is self-discharge rate and BEL taken into account while determining CEDV or initial SoC (on BMS reset)?

Power management

Power management forum

BQ78350-R1 : Use of ChemID in gauging apart from Initial Battery Capacity