Air bearings have been used in large centrifuges and gyroscopes.
It could be applicable to electric cars and also maybe more applicable in the AirCars that TATA is producing in India (and with plans here in the US). Where the air cars have a ready supply of compressed air they use for propulsion the electrics would need an electric motor to drive a compressor. The think is that since these bearings are frictionless the amount of energy used to feed the bearing only has to overcome the amount of energy normally consumed in friction. Not sure what bearings though... lots of bearings in any automobile, electric or otherwise. The thing is with air bearings the load has to be fairly constant. Could never use them in a recipocating mass like crankshaft, connecting rod bearings in an internal combustion engine. Would work in a turbo-charger though.
Yes they'd work, but not cost effective. Ball bearings already have very low friction. It's not worth the cost and compexity to go from maybe 2% friction to zero. You may even lose as it takes some energy to constantly pump up the bearings.
But air bearings are not typically exposed to shock and vibration, such as a car would experience when running over washboard roads or when hitting a pot hole. One good bump and your bearing would wipe itself out.
