We can't afford anything but batteries for cars. The energy efficiency of wind->hydrogen/synth fuel->movement is just too bad. We don't have enough room for turbines to afford losing a factor 5 in energy efficiency.
https://www.researchgate.net/profile/Markus_Reuss/publicatio...
Not enough room? You can build a floating solar panel, that just ships over the ocean, generating charged LOHC which then is collected by a automated ship.
PS: If you look at the references of this paper you can see the BMW research that is referenced.