STBCFG01 I2C not working when Battery is not Charging

Hello ST Community

&sharpSTBCFG01

I been in a situation with the charger/ Fuel Gauge IC STBCFG01 where, when the USB supply is removed(ie VCC_5V_USB) the I2C communication is not working. Which mean i am not able to monitor the Fuel Guage value when the battery is not charging .(VCELL+ is the battery terminal)

It is written in the datasheet that the IC can be used in mobile phone and smart phone, Where we only plug the battery when we need to recharge.

So how can I read the register when there is only battery voltage .

Datasheet:-

https://www.st.com/resource/en/datasheet/stbcfg01.pdf

Scuderi.Giuseppe