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Comment by carlmr | Hacker News Reader

In some special cases a transmission may make sense on an EV.

Electric motors are very inefficient at low revs. Most cars don't spend much time at low revs with a lot of torque output so this doesn't matter. But a car like a jeep that may haul a high load at low revs up a hill may be more efficient with a transmission.

Of course you have to account for the weight of the transmission and its inefficiency as well to see if it makes sense overall.

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Most EVs already have gearboxes, this also isn’t really a transmission it’s just emulating one with haptic and auditory feedback.

When you say "gearboxes" as in traditional multi ratio transmissions? If so, are you 100% sure about that?

IIRC the Tesla Roadster had a 2-speed transmission initially, due to engineering challenges with high-rpm bearings. But they struggled with the engineering challenges of high-torque transmissions, and eventually sorted out the bearing issues and went back to 1-speed.

Most EVs have a single-speed gearbox. A few have multiple gear ratios, but it's not common.

(It's not unusually for ICE vehicles converted to EV to retain a manual transmission, but conversions aren't being done in large numbers.)

For conversions you usually find an optimal reduction ratio for your motor and whilst you can reuse the transmission it’s fairly rare that you continue to operate it.

They have gearboxes with a fixed ratio that is optimal for the vehicle, some have variable speed gear boxes 2-3.

The motor isn’t just connected to the drive train in 1:1 that won’t end up well for neither the drive train or the motor.

Porsche Taycan has a 2 speed transmission: https://www.caranddriver.com/news/a28903274/porsche-taycan-t...

The article is about a fake transmission, but that's separate and mostly unrelated topic from whether other manufacturers might want to use a real transmission.

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