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There have been a number of electric cars that have used two electric motors instead of a single motor and differential.
It works well with electrics, because the motors tend to be compact, compared to engines.
The reason a differential is needed is so that the two wheels can go at different speeds (usually for cornering, turns), but there's more than one way to skin a cat!
The Tropica was an electric roadster mad by the same guy who designed the Citicar. It was rear-wheel drive with one motor on each rear wheel (connected by a belt and pulleys for gear reduction).
It had two DC motor controllers, one for each motor. On DC, you just switch the polarity to reverse the motor direction. One motor has to spin backwards compared to the other, because they are mirror images of each other, but both need to drive the car forward.
The motor controllers were mounted right next to each other, with the bus bars on both facing each other. Then an "X" of bus bars connected the power to both, but opposite polarities.
It was kind of a cool setup.
No differential needed!
On a DC system, you MIGHT be able to get away with connecting two motors to one controller, but not on AC.
Another advantage with two motors and two controllers is that you can potentially double the power of your EV.
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