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by orra 593 days ago
Precisely. Electric cars almost universally have one fixed gear, with the engine smoothly providing variable torque.
3 comments

This is a nitpick for sure, but as I understand it, electric motors provide pretty much constant torque throughout their operating range, which is one of their benefits. It's the speed of the motor that varies, and consequently the power, which is a function of torque times speed.
No, electric motors exert the most torque at zero RPM. That's where you can put the most current through the coil, because there's no back-EMF. It's why EVs are so zippy from a stop. The torque-speed curve is a straight line, with 0 torque at max RPM and a constant power.
For synchronous motors. Induction motors (like the auxiliary/dual motors used on something like the Chevy Equinox EV) have a different torque/speed characteristic.

https://www.engineeringtoolbox.com/electrical-motors-torques...

Sorry - not constant power, obviously, since at the extremes the power is 0.
I believe multi-motor EVs sometimes tune the motors to different uses, switching between one or the other (or both) to provide a similar effect as a gear shift.
this is a cost savings feature that was enabled by electric motor torque at low speed and the consumer's willingness to sacrifice high speed operation to focus on city driving.

electric motors hugely benefit from gearboxes, they're not used as a means to simplify and encheapen.