Wireless Electric Power Transmission

I read in a Popular Sience Issue from around 1950 to 1960 that they where developing a Car that would be feed trough the air with Electric Power, i also remember something about Tesla having used just such a car.
What where the reason that they never were build?

Uncle Cecil covered this is a column titled What’s up with “Broadcast Power”? Short answer: the technology either didn’t really work, or was horribly limited and inefficient.