I thought this range extender patent was cool until I started to do the math.Ford has patented an in bed 'range extender' aka generator. It will be interesting to see if they actually bring it to market and if you could possibly rent one for a weekend from the local ford dealer.
As far as putting a standard generator in the bed. From what I have seen on YouTube, people have a very hard time getting an ev to actually charge from an inverter generator like you would use for camping.
Even if Ford would find a way to enable Lvl2 charging while in motion, I don't think it will be feasible (OEM or otherwise) to use a portable generator as a range extender for such an inefficient vehicle. There have only been 4 vehicles that have used range extenders (ELR, Volt, i3 and Karma) and all of them were compact cars. Only one of them is still on the market (i3) which says a lot about the economics of series hybrids in general.
A 32-amp EVSE will add 10-15 miles of range per hour at best. The most analogous setup to the Ford patent is a bed-mounted home standby generator capable of powering the 80 amp EVSE. Even, then you'd have to deal with >500 pounds and >$5000 worth of generator and would probably only get 40 miles of extra range per hour. For that payload and price penalty, ford would better off making a bigger built-in battery pack or offering an external battery pack.
That said, I will probably travel with a portable generator as a safety blanket on longer trips with the RV.