BQ27500-V100: Calibrating fuel gauge or can a default profile be used?

Amy Douglas

Part Number: BQ27500-V100
Other Parts Discussed in Thread: BQ27500

Hello,

I am using this fuel gauge with 18650 cells but I am confused as to whether I need to calibrate the fuel gauge to work with these cells or not.

In the datasheet it says "The bq27500/1 acquires and updates the battery-impedance profile during normal battery usage.". Does this means that I can just plug in my cell and run it and the fuel gauge will update over time? Or does it still require calibration using the bqEASY software?

If it does require calibration then is there a default profile for 18650 cells that I can use?

Thanks in advance!

Amy

over 3 years ago

0 Wyatt Keller over 3 years ago

TI__Guru** 103235 points

Hello Amy,

You should calibrate the current and voltage of the gauge, you can follow the app note for quick start with the gauge: www.ti.com/.../slua448.pdf

Sincerely,

Wyatt Keller

0 Amy Douglas over 3 years ago in reply to Wyatt Keller

Prodigy 130 points

Hi Wyatt,

Thank you for your quick response. Can you please confirm for me, does this mean using the bq Gas Gauge Evaluation Software that I only need to calibrate the current and voltage under the calibrate tab for the fuel gauge to work accurately with my cell? Meaning I do not need to complete the full bqEASY calibration cycle, etc.

Thanks!

Amy

0 Wyatt Keller over 3 years ago in reply to Amy Douglas

TI__Guru** 103235 points

Hello Amy,

This gauge is older and only has 2 chemistry profiles to choose from, but a learning cycle is needed for the gauge to calculate the Qmax and Ra values.

Sincerely,

Wyatt Keller

0 Amy Douglas over 3 years ago in reply to Wyatt Keller

Prodigy 130 points

Hello Wyatt,

Thanks again for your response. Are there any default .dfi files that can be used for specific cell types to provide the Qmax and Ra values or is a bqEASY calibration cycle the only way to achieve these values?

Thanks again!

Amy

0 Wyatt Keller over 3 years ago in reply to Amy Douglas

TI__Guru** 103235 points

Hello Amy,

The only way is to cycle the batteries, the Ra and Qmax are specific for your pack and cannot be programmed with a default configuration file.

Sincerely,

Wyatt Keller

Power management

Power management forum

BQ27500-V100: Calibrating fuel gauge or can a default profile be used?