I know electric cars don’t need multiple gears, but wouldn’t they benefit from them in anyway at high speed for example?
In: Technology
Internal combustion engines (almost all) have to convert up-and-down motion to pure rotational motion. If you are cruising along the highway, your engine is probably doing 3,000 rotations per minute. For each and every rotation, the piston has to come to a complete dead stop at the top (top dead center) and the bottom (bottom dead center). After it comes to a complete dead stop, it has to accelerate like mad, only to have to stop again at the bottom.
All this stopping and starting is hard on the internal bits. Most engines *really* don’t want to go past 5 or 6,000 RPM. The engine would literally fly apart because all those forces just got too crazy big. So it’s not just an efficiency thing that cars with gas or diesel engines need a transmission. It’s to keep the rpms down in the non-explody range.
Electric motors don’t have any reciprocating parts. It’s all rotational. No converting. No stopping and starting 6,000 times a minute. It is trivially easy to design an electric motor that zooms all the way to 20,000 rpm. Plus, they make waaaay more torque at very low rpms. They have a huge band of efficiency across a huge rpm range. Thus, no transmission.
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