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Tiny electric motor can produce more than 1,000 horsepower

supercarblondie.com

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Re: Tiny electric motor can produce more than 1,000 horsepower

#401

Post by dghlsakjg »

amluto wrote: post #383
eightysixfour wrote: post #319

Earlier quoted context omitted.

The size of this motor is moderately interesting, but the power density doesn't really matter for most of the things you just mentioned. Almost every one of them is limited by the amount of batteries you can put in for both weight and power output reasons.

What do you mean? Modern LFP cells have quite high power density. LTO is even higher. An e-bike with a 100Wh battery and a 300W motor would be extremely useful if it were light enough: you could carry it up stairs, onto trains, etc easily, and it would give plenty of boost to navigate traffic for short distances and make it easier to go up hills. The idea would be that most of the energy would come from the rider. 10…

I'm super excited to fly an electric plane, but a lightweight motor isn't what's gonna make that possible. My current plane carries 561 kwh of energy in a 100 pound/ 17gal gas tank.

Even if you say the engine is only 30% efficient, I am still carrying an absolute shitload of energy compared to what I could get out of 100 lbs of lithium batteries.

The actual motor only weighs 84 lbs.

So I have a weight budget of 184 lbs (call it 200 just to be safe), and current capability is a peak output of 50hp (37 kw) and a cruise endurance of 3 hours at 40 hp / 30 kw. So just to math it out, lets say I will need about 90kwh of battery to come close to my current gas capabilities. At an extremely generous 5 kg per kwh, I need a battery that weighs more than my entire airplane's max gross takeoff weight. The weight of the engine is completely irrelevant when the battery weighs 450kg.

Re: Tiny electric motor can produce more than 1,000 horsepower

#402

Post by nomel »

reactordev wrote: post #57

Axial flux motors are so next level. Very little power needed per rpm. I’ve built a few tiny ones for FPV and they are a joy to work with. I’ll die a happy man if I never have to coil again.

Coils are still required for axial flux motors, they're just in a different orientation [1].

[1] https://www.youtube.com/watch?v=dCO633KE7RA&t=510s

Re: Tiny electric motor can produce more than 1,000 horsepower

#403

Post by mywittyname »

Empact wrote: post #354
Aurornis wrote: post #251

Earlier quoted context omitted.

> Could lead to significant efficiency gains for EV's, because 1/4 of the motor weight means better power-to-weight ratio... a lot of things will automatically get better. EV motors are already lightweight. The electric motor in a vehicle like a Tesla Model 3 already weighs less than you do. Reducing that one component by 75% would be a weight savings equivalent to about a half of a passenger. Not a significant effic…

This, or a miniaturized version thereof could change the game for light electric vehicles - imagine an electric motorcycle that weighs substantially more like an electric bicycle. Right now it takes about 10-15lbs of motor to produce a 3KW motor for an electric bike, this motor is about 10 times that in power density afaict. The Livewire electric motorcycles use something like 100-200 lbs of motor to produce 1/4 as m…

Does this motor design scale down? It's not clear from the article - the article focuses more on the relative efficiency gains over the previous model.

A 30lb 1000hp motor doesn't necessarily mean that they can also produce a 3lb, 100hp motor. It would be cool if it did, but I doubt that it does because usually component strength doesn't scale linearly.

That being said, these are still valuable for traditional EVs. Even if they are only a modest weight savings in the grand scheme of modern vehicle weight, their ability to improve packaging options will be a boon. One thing the industry has dicovered is that the generic "skateboard" platform doesn't make for the best vehicles, in terms of packaging.

Re: Tiny electric motor can produce more than 1,000 horsepower

#404

Post by nsxwolf »

eikenberry wrote: post #363
bhhaskin wrote: post #361

Earlier quoted context omitted.

There is a big issue in the US currently with people buying electric motorcycles that look like e-bikes.

What is the issue? I've seen people on those bikes and they look fun to ride.

My neighborhood is full of kids on these things. The safety dynamics of driving around have changed completely. Small children flying on and off road at high speeds. It's crazy.

Re: Tiny electric motor can produce more than 1,000 horsepower

#406

Post by RajT88 »

fukka42 wrote: post #393
RajT88 wrote: post #375

Earlier quoted context omitted.

I see kids blasting around at high speeds without helmets. Kids treat them like fast bikes you do not have to pedal. Wiping out on a bike at 13mph is a very different proposition to wiping out on a bike at higher speeds. I saw just a couple nights ago some kid doing what appeared to be about 40mph on an eBike. Wind in his hair, not pedaling, just blasting it. I am sure new regulations will come to speed limit them, b…

[flagged]

Not really...

https://www.reddit.com/r/AskAmericans/comments/184oag8/can_y...

That assertion seems to be a disconnect of language. But - Selling firearms in Wal-Mart is bad enough, but it does tend to be more rural Wal-Marts than suburban (and not at all urban).

Said firearms are under lock and key in the same way they would be at gun stores. There are many gun shops in the same areas where Wal-Mart sells firearms. At least - where I live, which is a blue state. All bets are off for Texas.

Re: Tiny electric motor can produce more than 1,000 horsepower

#408

Post by Qwertious »

hamdingers wrote: post #260
DrScientist wrote: post #157

Earlier quoted context omitted.

It compounds. If you have a lighter more efficient motor you need a smaller battery for the same range, that combined weight loss means you meed lighter brakes etc etc, and because the car is now lighter you size of your motor you need is less..... They claim, this compounding effect works out to basically double the effective weight saving from battery and motor. ie if you start with saving 50kg on motor, and 50kg o…

> If you have a lighter more efficient motor you need a smaller battery for the same range Nitpick: You can have a lighter motor, but you're never going to have a significantly more efficient motor because existing EV motor systems are already 95% efficient or better. The electric motor is an old and refined technology.

Suppose you go from a 95% efficient electric motor to a 99% efficient motor. How much more efficient is it? You might say 1.04x (or actually 99/95 efficient). Except, that's not the whole story - electric motors need cooling, and you've just dropped the heat output five-fold (going from 5% heat to 1% heat). Lower heat output means less venting needed and thus better aerodynamics.

Re: Tiny electric motor can produce more than 1,000 horsepower

#409

Post by RajT88 »

bhhaskin wrote: post #380
RajT88 wrote: post #375

Earlier quoted context omitted.

I see kids blasting around at high speeds without helmets. Kids treat them like fast bikes you do not have to pedal. Wiping out on a bike at 13mph is a very different proposition to wiping out on a bike at higher speeds. I saw just a couple nights ago some kid doing what appeared to be about 40mph on an eBike. Wind in his hair, not pedaling, just blasting it. I am sure new regulations will come to speed limit them, b…

And here is the problem. They are already supposed to be speed limited if it's an e-bike. It's easy to tell the difference between a bicycle and a motorcycle, but the difference between an e-bike and electric motorcycle is far more subtle. And most electric motorcycles lie and market themselves as e-bikes.

> And most electric motorcycles lie and market themselves as e-bikes.

Because they have pedals which nobody uses. In theory, it's pedal assist, but kids aren't really pedaling eBikes, they are using them like electric motorcycles.

You might think: Hey, how can you tell the difference between somebody using an eBike with pedal assist if so many of them look just like regular bikes?

I don't really see young people pedaling bikes at all of any kind. It's adults who don't have cars, or adults who are exercising pedaling bikes.

Re: Tiny electric motor can produce more than 1,000 horsepower

#410

Post by hiccuphippo »

port3000 wrote: post #124
bigtones wrote: post #100

Earlier quoted context omitted.

Americans are very weird when it comes to metric. They often quote mobile phones as having something like "a six inch screen size but now only 12mm thick" - pick a measurement system people !

The inch thing is because it's a screen: all screens are measured in inches pretty much everywhere, even in the EU

And I hate that. Wish screen sizes were measured in centimeters.
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