Are you still sticking with that it is theoretically impossible?
For a car that can carry four people and their cargo, can achieve a good crash safety rating, has heating and air conditioning, and can cross mountain passes on I-70 in Colorado at night, while keeping up with traffic (and do all those things at the same time)? YES!
Did you also feel that way 15 years ago when someone said that a Tesla or Leaf were possible?
No, because electric cars charged from the grid have always been relatively feasible.
(I say "relatively," because even the Tesla or Leaf would have much better range and much lower "recharging" time if they stored their energy as hydrocarbons instead of in a battery! The reality is that even the "successful" Teslas and Leafs
are still niche products.)
Moreover, there is no fundamental limit determining the energy storage of the batteries we have now. Even if somebody proved that chemical batteries could not be improved versus the best battery tech today (or 15 years ago), we've always known that other kinds of energy storage (again, hydrocarbons -- or nuclear) with far greater densities are possible, and that it's generally possible to convert other forms of energy into electricity to drive an electric car. From that standpoint, electric cars have always been "possible."
Solar irradiance, on the other hand,
is a fundamental limit.
Will we need airbags 30 years from now when all cars are autonomous and there hasn't been an accident in a decade?
That depends: will we have exterminated all the deer, dogs, small children, and everything else that can jump into your path and cause an accident that even an autonomous car can't avoid by then?