Thanks for all the replies. I had a look at the video and I looked
under the hood, and sure enough there's a generator there.
I still find it curious that there is need for a generator when the big Li ion battery is charged by the sync motor.
There is no lead-acid 12 volt battery used as far as i know. I've heard that they have taken a little slice of the big battery to do the 12 volt work. Also, I've listened to radio while the ignition is in 'acc' mode and a notice comes up almost immediately suggesting that I run the engine so not to discharge the battery.
I wonder what the watt-hour rating of the 12 volt slice is??
Just one more thing, the generator appears to be liquid cooled! There are a couple of hoses connected to the body of the generator (even shown in the video). That should be a very high output device if it needs liquid cooling.