I was wondering if the Tesla Semi truck had a bed.  

As far as we know, the Tesla semi-truck does not come with a bed.

A semi-truck is a huge, cab-over-engine truck that is commonly used to move cargo.  

The Tesla Semi's ability to haul up to 80,000 pounds of freight comes from two battery packs mounted

on either side of the cab, in place of the standard boxy cargo bed. It has a one-of-a-kind layout  

and can accommodate up to four people; it also comes equipped with high-tech sensors, radar,  

and a full-circle video system. The vehicle's four motors are all separate but complement each other,  

In addition, extended trips and heavy loads don't degrade battery performance because to Tesla's active battery management