If you are really warring about atmosphere, You should start working with government. Just government can create a law of saving a nature(atmosphere) and in the same time to help advertise an electromotor.
Moreover if US government will start work with another governments of the world, you can start selling your electromotor to the famous brands. But selling your electromotores does not mean that you should sell innovative elecromotores.
It will take time and money, but finally your car gonna have massive interest because your cars, with the same electromotors like famous brands have(your electromotor with updates), will have better speed and better car's design for works properly with electromotores.