Electric Cars Are Gearless ?

Abhishek
Member • Jul 5, 2013

Electric Cars Are Gearless ?

Here in Ahmedabad, I daily watch an old lady driving a small sized car, running with electricity. i have heard some of my friends discussing about it & they say that Electric cars / vehicles don't have gears.
I don't believe them, so I wanna re-confirm that whether it is true ?
If yes! then why Electric Cars don't have gears ?
Even solar cars don't have gears ?
Can anyone explain technical reason behind this ?

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Kaustubh Katdare

Administrator • Jul 5, 2013

The Torque produced is enough for the vehicle to get into motion at any speed. I read that the Tesla cars have gearboxes; but I'm not at all sure why'd they need one. Marking #-Link-Snipped-# .

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Harshad Italiya

Member • Jul 5, 2013

I think that is because of the motor being used in the CAR. As BLDC motor is used in Electric Bike. There may be same but powerful BLDC motor in Car too and that's why there is no gear mechanism.

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zaveri

Member • Jul 5, 2013

It all depends on the design.

if the motor produces enough torque to take the load of the car as well as the passenger then you dont need a gear box.

however you may still require a gear box to increase the speed, but at the cost of the motor torque.

#-Link-Snipped-#

is that car a Rewa ?

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Abhishek Rawal

Member • Jul 5, 2013

#-Link-Snipped-# Yes man, it's Rewa. I didn't remembered the name until you spelled it.

So, if we increase the passenger space we'll need the Gear box, right ?
Is there any electric running car with gear box ?

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zaveri

Member • Jul 5, 2013

Abhishek Rawal
#-Link-Snipped-# Yes man, it's Rewa. I didn't remembered the name until you spelled it.

So, if we increase the passenger space we'll need the Gear box, right ?
Is there any electric running car with gear box ?

Yes if you increase the passenger space or the kerb weight of the car, you will need a gear box to step up the torque.

so far rewa is the only electric car which i know can be found running on indian roads, and in Chennai they are extremely rare.

not sure whether rewa itself is geared or automatic.

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zaveri

Member • Jul 5, 2013

another such car is the renault twizzy.

There is another manufacturer called POLARIS who manufactures small cars which can be driven without licences.

but i am not sure whether those cars are powered by electric motor or I.C engine.

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Sarathkumar Chandrasekaran

Member • Jul 5, 2013

I searched on the web and found the interesting thing that electric cars produce sufficiant torque to move the car from a stand still position and also produces high rpm .
One of the main reason for usage of gearboxes in automobile is for reversal of vehicle. Hence gearboxes were used in ic engined cars.
But in the case of electric cars , the reversal or change of direction of current can move the car in reversal direction(I think so).
Hence electric cars dont require a gear box under normal conditions.

Solar cars follow the working of electric cars and I think they also dont need a gear box

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gohm

Member • Jul 8, 2013

They do indeed, the roadster for example had a single speed, fixed gear auto tranny. Not only would this assist in power delivery/transference but it also allow the car to have park, neutral and reverse.
Kaustubh Katdare
The Torque produced is enough for the vehicle to get into motion at any speed. I read that the Tesla cars have gearboxes; but I'm not at all sure why'd they need one. Marking #-Link-Snipped-# .

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Rishabh1234

Member • Sep 25, 2014

i have heard something about the use of planetary sun gears in electric vehicles . please anyone throw some light on it

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Shashank Moghe

Member • Sep 29, 2014

Does Mahindra Reva have a gear box?

Yes. #-Link-Snipped-#

Do all EVs have a gearbox?

No. #-Link-Snipped-#

Do EVs need a gearbox?
(I read this on some blog, this isn't entirely my answer. Forgot the name of the blog.)

- Partially No.And Yes. Electric motors have a flat torque curve, which means that they can produce high torques almost instantaneously. I read the motor can go to 20000 rpm producing peak torque, directly from standstill. Hence, all the motoring needs (load) can be achieved without a gearbox.

IC engines, on the contrary, have a max rpm limited to 10000 (being very optimistic, beyond most redlines), hence, need a gearbox to optimize torque and power delivery.

But as mentioned earlier, the power output from an electric motor can be optimized with a suitable gearbox. Of course, just because the motor can go to 20000 rpm doesn't mean it needs to.

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