I might be wrong and I likely am. It just seems to me that the auto engineers have bypassed the opportunity to rid electric cars of one of the weaknesses of cars, the differential. Ever since cars have made their entry on the scene they have had a weakness. Getting power from both power wheels and still allow them to turn at different speeds. It is why it is called a differential.

Many things have been done to resolve this problem with some success. Even so, at best it is at substantial cost and reliability. Positraction helps in situations where one of the power wheels may slip. Some of these possibilities include sand, ice or even loss of contact with the road.

As far as I know, all or most electric cars have one electric motor for each set of drive wheels. The 4 wheel drive cars use two motors, one for each set of wheels. At least this has some advantage. Power is delivered to the front and rear wheels separately which does permit maximum torque for front wheel and rear wheels independently. However, in this situation, there are two differentials, on each on the back and front wheels.

So, when they came up with electric cars, why one motor? Why not one motor for each wheel?

Well, as I said, it’s outside my knowledge. Still, it does make me wonder just how successful a car would be with two motors. I guess, a single motor failure might be a problem, but how often is that going to happen. Moreover, the car could be designed so that if one motor quit, the other one would too.

Then the question comes to mind, is the cost of two motors more than the cost of a differential. Also, the differential does add weight and reliability considerations.

The one thing I certainly have no understanding of, how would the car drive with two motors, with perhaps different torque to the wheels. Perhaps, tests would have to be made on the motors to get two matched motors. That in itself would add costs.

I don’t know. My wife is always telling me I think too much. Maybe I do.