now, I have logged the I2C communication to BQ24150 for a whole charge-discharge-cycle.
I deleted lots of unnecessary lines from the logfile, but kept some stuff which is not directly related to i2c.
All i2c entries are just to device 0x6b (ensured by if-statement in the kernel sourcefile, logging all i2c-messages would be way too much to analyze)

I found out the following times which might be interesting:
- 00:29:07 started charging
- 02:16:23 battery is full (after that: sometimes charging, sometimes not => patented battery management )
- 09:07:11 unplugged charger
- 19:28:19 shutdown because of empty battery

the whole day, nothing was plugged into the usb port (I only played lots of videos to discharge the battery quickly )

attached you find an image from batterygraph showing the charge/discharge. the log is too large, therefor its here (2,5MB)