Yep totally agree about the batteries and that is well reported...

Yep totally agree about the batteries and that is well reported in the market place.
The Tesla Semi release is on 1st December when all will be revealed. It appears the 2170 batteries are being used currently transitioning into the 4680 when they get the 4680 battery production perfected. I did hear that the batteries may well be LFP versions out of the Shanghai factory long range Model 3/Y but not sure about that. That might just be the rumour mill.

Elon said, "We designed the Tesla truck to be like a bullet, whereas normal diesel trucks are designed more like a barn wall; this is a bullet," said the Tesla CEO. The Semi can generate the performance and the range due to the design. The drag coefficient or wind resistance of the regular diesel trucks is a 0.65 to 0.70. The Tesla Semi scores a 0.36, cutting the regular diesel truck drag in half and even beating the Bugatti Chiron score of 0.38.
Another article I read stated the Tesla Semi is expected to have a battery pack with 600kWh to 1MWh so should be a pretty significant battery pack.

Don't forget Elon has been using the Tesla Semi since 2018 running to and from the Fremont factory, so has been busy gathering data and performance in that time.