Why do electric cars only have 1 gear?

>>9153235
Because gearing is unnecessary. You wouldn't need gears on an internal combustion engine setup either if they could handle the broad range of torque and speed an electric motor can.

>>9153235
why the fuck would you need a gear ? you get all the power at any angular velocity of the wheels .making shit that requires gears is kinda stupid in comparison .

>>9153251
Yeah but changing gears at redline rpm is cool

Why doesn't [insert appliance with electric motor] have a gear?

Formula E uses gears and it's 100% electric
Sage

>>9153235
Internal combustion engines have a very high and narrow peak when you graph their power output versus their rpm. So isca narrow optimum band you want to keep the engine at. In contrast electric engines have a very broad and flat peak so there is a very broad range rpms that are at or near optimum power output.

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>>9153235
because electric motors tend to have flat torque speed curves and combustion engines don't.

Making electric motors with changeable gears has been proposed to change operating characteristics. IE changing between characteristics best for offroad or on-road driving.

pic related

Because of the electric motor having it's highest torque starting from zero rpm up to a resonably high rpm that we can do without shifting gears. That is, you can drive the electric Formula E car from zero to more than 100km/h in just one gear (3rd gear, may be). But in racing they require higher torques for higher accelerations (1st and 2nd gears) and high speeds (4th and 5th gears).

The electric motor torque does drop at very high rpm. And the old combustion engines torque peaks at mid rpm, not to mention it does not run below 700 rpm.

>>9153272
It's not unusual for a reduction box to be used on conjunction with an electric motor.
It increases torque, lowers/controls speeds and cuts down amperage.
Electric cars have gears.

>>9153235
For those within this thread who have no idea, a transmission in your typical car has various gears, and these gears determine how fast the output shaft rotates compared to the input shaft (crankshaft). For example, I will be using a 4R70W:

First 2.84:1
Second 1.63:1
Third 1.00:1
Fourth 0.78:1

At the third gear, the crankshaft and output shaft turn at the same speed. A car is limited by its transmission highest gear ratio and maximum engine RPM. A car has a maximum speed that it reaches that it can no longer top.

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one gear
or
∞ gear
?

>>9153273
SOME forumla E cars use gears as a design choice by the various team because they provide benefits in RACE scenarios, read a fucking book idiot.

You dont need gears for an highway electric car because electric motors have very high torque and operate at high revs.

electrical cars have only one gear because the maximum speed of the car, FOR AC MOTORS is mainly determined by the frequency of the voltage applied to the stator windings.the speed itself is a function of the voltage amplitude/frequency/load conditions and particular motors characteristics but with inverters you can easily control both the amplitude and the frequency of the voltage so in theory you don't need gears but i dunno if EV actually use them, FOR DC MOTORS you can really only manipulate the voltage applied to the motor so for those cars there might be a need for gearing but again this is only in theory, even for AC there's differences with using low or a high frequency, for low frequencies there might be too much losses due to way too high magnetizing current vs actual load current needed to develop torque and for higher frequencies you start having core losses and joule losses due to skin effect

>>9153945
*higher core losses and joule losses

>>9153860
>OP: Why doesn't X use Y
>Him: X does sometimes use Y
>You: SOME X uses Y because it has advantages retard
wat

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>the you don't want electric cars because it means no more shifting while on the touge

>>9154212
well you could use software to replicate the feel of shifting.

Or you could put hub motors on ever wheel with active suspension, camber adjustment, independent turning, and use a controller that optimizes for maneuvering performance rather than comfort and let it jerk you around. We're talking being able to turn 90 degrees on a dime going fast.

electric cars can benefits from having multiple gears. it just isn't worth the extra weight and cost for most cars.

in fact the dual motor awd Teslas use different gearing for each motor set. so one motor is geared to be more efficient at highway speeds, and the other is geared to be better for acceleration at low speeds.

Why do internal combustion engines have such highly variable power outputs at different RPM?

>>9153235
>Why do I not know some electric cars have multiple gears?
because ignorant

>>9153270
>electric
>rpm