
Shut Up About the Batteries: The Key to a Better Electric Car Is a Lighter Motor - mcspecter
http://spectrum.ieee.org/transportation/advanced-cars/shut-up-about-the-batteries-the-key-to-a-better-electric-car-is-a-lighter-motor
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sunstone
As I recall Siemens has an electric motor that weighs about 100lbs and puts
out over 300hp. So yeah, it's all about the batteries still.

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rurban
No, it's not. Doppelbauer is absolutely right. He just forget one key strategy
with these high dynamic dynos. You make them longer, called cigar. The longer,
the more area to apply the force. But then you've got a problem with the
tyredyno design. The best cigars are 150cm's long, the ones used to test the
best F1 engines. Those are handmade in low numbers, and extremely powerful and
sensitive. They always need to need to know the exact absolute angle of the
rotor, which is a hard mechanical problem. Wrong cooling fluid will break the
engine. Only very few such engines do exist, but they are multitudes better
than any cheap engine. Such dynos usually win F1 championships.

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schiffern
>There are two kinds of AC motor: asynchronous and synchronous. We will focus
on the synchronous ones because they generally perform better and more
efficiently.

fwiw Tesla disagrees. True the _peak_ efficiency is better, but the average
efficiency is worse.

[https://www.tesla.com/blog/induction-versus-dc-brushless-
mot...](https://www.tesla.com/blog/induction-versus-dc-brushless-motors)

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lithos
Synchronous motors can be nice where you have predictable loads, well thought
out maintenance schedules, and few surprises. Or worst case just can't deal
with AC.

Almost nothing falls in that category.

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FullyFunctional
The headline promised a lot but the article delivered "4.4 percent less
energy". Also, I find it interesting that the motor Tesla uses isn't even
mentioned (and AFAICT doesn't fall in categories they compare).

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anigbrowl
Good article & technological work, but good luck finding collaborators with
the arrogant attitude radiating from that headline

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qbrass
Made even worse since it probably wasn't the authors who gave it that
headline.

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SigmundA
Tesla S motor and inverter weighs 350 lbs on par with an ICE. The battery
however weighs 1200 lbs while 20 gallons of gas weighs about 120 lbs.

No its all about the battery weight, and cost.

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rausk
Could it still be about the batteries:
[https://en.wikipedia.org/wiki/Energy_density](https://en.wikipedia.org/wiki/Energy_density)

Seem it is hard to beat the WH/kg of chemical energy storages with
electrochemical energy storage.

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sliverstorm
I agree we could really use improved batteries, but- You may not have to beat
chemical energy if you can improve aero, weight, and efficiency.

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alberthartman
So if you make your motor 10 pounds lighter you win? Heck, my backpack is 10
pounds. And a motor can only be 100% efficient, and they're at 97% now. Naw,
I'll take my non-slipring motors.

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sc0ttyd
Not even gonna read it even though I might be interested, due to the patently
false clickbaity headline

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tdb7893
Generally it is perfectly valid to judge a book by it's cover but the article
is actually pretty different in tone from the headline so I think it's
actually worth a read.

