He doesn’t expect to sell any cars nor does he even plan to go into production. This is PR to draw investors. If there were real-world benefits here he’d quietly make a deal with an established automaker.
The claimed performance stats does seem to be way out there. My general assumption is that if they were anywhere real, there would be a lot of interest.
But, although I have doubts, I couldn’t say for sure if salt-water had that much energy to draw out.