With respect to above specs.
Fully charged if I hit the highway at 60 mph the battery will be dead in 1.12 hours giving a range of 67 miles.
If I add a small trailer on the back with a small generator the following happens
1kw 1.20 hours 72 miles
2kw 1.29 hours 77 miles
3kw 1.4 hours 84 miles
4kw 1.5 hours 91 miles
5kw 1.6 hours 100 miles
6kw 1.8 hours 110 miles
7kw 123 miles
How hard would it be to wire in a 6k generator?