I’ve never seen an ICE car need two engines to drive all four wheels. Why do EVs need 2 motors? Wouldn’t a transmission be cheaper than another motor?
Thanks everybody!
Eclectic drive is MUCH easier to implement and two systems at 1/2 Power or capacity is much easier - - and the need to have the “tunnel” through the floor plan is a big design negative.
Basically ICE suck - aside from all of the efficiency issues -
While you could have an all-wheel drive system with a transfer-case/center-differential in an EV, it would have worse performance in most scenarios coupled with much higher losses. By minimizing the amount of parts the electric motor(s) have to spin, you reduce losses and improve efficiency.
Needing to package drive shafts throughout the length of the car eats into passenger room too, that’s why so many ICE cars have rear transmission-tunnels.
The one scenario I can think of where a center-differential/transfer-case would fare better is with lockers in an off-road situation.
Because it’s a lot simpler and less prone to breaking. Tough break for automakers that pride themselves on their transmissions but great for the consumers.
Electric motors are crazy cheap compared to the rest of the car.
And making 2/4 small ones is cheaper than making 1 really big one plus all the transmissions and drive axles needed to move power around the vehicle.
Likely cheaper doing it with two motors vs. one motor and a transmission system to all four wheels. More weight, more friction losses, more stuff to go wrong and less control vs. two motor. Only plus would be larger motors are more efficient, maybe 5% between 2 x 100 and 1 x 200 motor?
Could Subaru put a 200 HP electric motor in an Outback and run the wheels on the existing transmission?
Cost and opportunity. A transmission is hundreds to thousands of parts and requires a whole assembly line just for it. Motors are required no matter what and they’re simple to build compared to a transmission. They can be controlled via software, which is more reliable and cheaper than making a mechanical link with all real estate, personnel, energy, and resources required to make such systems.
Not an expert but my understanding is that electric motors are pretty cheap. In fact, all of the key components of an EV are cheaper than ICE – except the battery and HV systems.
So it’s relatively easy to add another motor, something that’d be much harder an more expensive in an ICE.