• Resolved

BQ34Z100-G1: SOC estimation shows jumps during first discharge cycle

Intellectual 680 points

Replies: 3

Views: 85

Part Number: BQ34Z100-G1

Hello,

Below the description of two (2) situations which requires help for clarification:

1. The SOC estimation after the a 12.8V LifePo battery (10000mAh) get 100% SOC and is discharged with constant current shows jump of 10% at the end of the discharge. After the first cycle, the SOC estimation seems OK. Below the waveform with V, I and SOC.

2. The SOC estimation is hold during constant discharging. Some of the device present this situation while other not.

The SMOOTH is enabled.

Attached firmware file (srec) for reference.0100_0_16-bq34z100G1- Copy.zip

Thanks

  • Hi Lao,

    This is because of both the smoothing feature and the RSOC_HOLD feature.

    Smoothing has 2 points where it will allow a jump. One is from any value to 100% and the other is from any value to 0%. So, in your case, the IT simulation determined that your capacity was zero at the point where it dropped to 0%. Therefore RSOC jumped to 0.

    In the second case, we have what we call as IT simulations or remaining capacity simulations that run during dsg at certain points called grid points. It is explained here, . So at these grid points, if you have smoothing enabled, RSOC will stay flat at dsg to allow charge to catch up if the estimated capacity is higher.

    Regards,

    Batt.

  • In reply to Batt:

    Hi Batt, thanks for the description of both situations and the application report reference!

  • In reply to Lao Hu:

    Hi Lao,

    You are very welcome. Thank you for using the gauge.

    Regards,

    Batt.