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Comment by ape4 | Hacker News Reader

And now differentials are basically obsolete - not needed in electric cars.

Why is that? Tesla Model 3 for example uses 1 or 2 motors, not one per wheel, so they still need to add variable speed to left vs. right wheels, right?

I don't understand either. Somebody else made the same comment but typical electric cars still have diffs. Examples include Chevy Volt, Nissan Leaf, and Tesla Model 3, Tesla Model S. Where are the electric cars with independent left/right drive motors? Even cheap toy electric R/C cars have differentials.

Model S Plaid edition, in theory the top end cybertruck and the new roadster.

What's the point of a differential for wheels that aren't driven? Why even connect them at all?

https://en.m.wikipedia.org/wiki/Electronic_differential - and it indeed requires separate motors for each driven wheel.

Not true, only if you have each wheel powered can you dispense with a differential. Since that is not efficient (granted it sounds cool - that old pen/paper car wars game cool) most BEVs run one or two engines.

Remember, the idea is to handle the situation when torque on one wheel is not the same as the opposite wheel. Now it can be done with an electronic LSD which applies braking force

They aren’t needed in fossil fuel based cars either if you have an engine for each drive wheel. But most electric cars still employ a differential on one or more axles, even Tesla. Typically, due to cost, packaging, or performance, you have more drive wheels than motors and a differential is necessary.

They are totally needed in (parallel) hybrid cars. Two engines of possibly varying speed moving a car are very much like one engine moving two wheels of possibly varying speeds. Both need a differential.

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