BQ40Z50-R1: FCC jumps at low temperature, recovers after being placed at room temperature

guoqing shi

Intellectual 355 points

Part Number: BQ40Z50-R1

Does the FCC change in real time with the temperature or it takes a certain amount of time，

Can the mechanism of FCC change with temperature be briefly introduced?

over 3 years ago

0 Wyatt Keller over 3 years ago

TI__Guru** 105810 points

Hello Guoqing,

The FCC update conditions can be found in SLUA450: https://e2echina.ti.com/cfs-file/__key/telligent-evolution-components-attachments/00-24-00-00-00-00-02-91/Theory-and-Implementation-of-Impedance-Track-Battery-Fuel_2D00_Gauging-Algorithm.pdf

Update of RM and FCC takes place after each resistance grid-point update, at the end of discharge, and at the exit of relaxation mode. FCC consists of three parts: DataRAM.Full Charge Capacity( ) = Qstart+ PassedCharge + RM()

It is also outlined in the TRM for the specific gauge being used:

• QMax update occurs

• Ra update occurs

• At onset of charge and discharge

• At exit of discharge

• Every 5 hours in RELAX mode

• If temperature changes more than 5°C

Sincerely,

Wyatt Keller

0 guoqing shi over 3 years ago in reply to Wyatt Keller

Intellectual 355 points

For the last item "If temperature changes more than 5°C", how to determine the end of the temperature change,

need to detect whether the temperature is constant or the temperature is changing (once it exceeds 5°C), the FCC update will occur

0 Wyatt Keller over 3 years ago in reply to guoqing shi

TI__Guru** 105810 points

Hello Guoqing,

Do you mean when the gauge will look at the temperature difference? If there is a 5degC change from the last FCC update that's when it will do another update.

Sincerely,

Wyatt Keller

Power management

Power management forum

BQ40Z50-R1: FCC jumps at low temperature, recovers after being placed at room temperature