Other Parts Discussed in Thread: BQSTUDIO
ADC measurements are taken only once per second. Due to this it is recommended data only be read at a 1Hz rate. The firmware is not designed to be read from at a rate faster than 1 second for a single register, most of the resulting data will be the same as the previous read until it updates again at the 1Hz frequency.
If you are using BQStudio ensure that it is the test version as s it is the most updated and has the most features. Auto-refresh should be disabled in addition to any logging/scanning before reading any data to avoid communication collisions.
For a detailed guide on I2C communication with this gauge look at this app note: