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Tiny electric motor can produce more than 1,000 horsepower

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

#491

Post by RajT88 »

gambiting wrote: post #474
RajT88 wrote: post #409

Earlier quoted context omitted.

> 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 peda…

>>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. Where do you live - over here(North of England) most kids ride bikes, especially to school. And not ebikes either - actual regular pedal bikes.

Chicago suburbs. Cultural difference, mayhap.

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

#492

Post by beefnugs »

mperham wrote: post #356
Empact wrote: post #354

Earlier quoted context omitted.

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…

There’s no area in the world that allows e-bikes with more than 750w motors. A 3kw motor is illegal (cf Surron), unless you are talking about an e-moped requiring registration.

Oh nooo i have to put a sticker on it, and only allow my control to go to some arbitrary value when the cops are watching

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

#493

Post by dotancohen »

mattlutze wrote: post #400
huijzer wrote: post #389

Earlier quoted context omitted.

Exactly. Main problem is battery energy density. Cars can drive about 20 kilometers on 1 liter of gasoline. In comparison, Tesla's 4680 cells are at about 272-296 Wh/kg and CATL's Kirin Battery at about 255 Wh/kg. A bit efficient EV often uses 200 Wh/km, so for 1 kg of battery the electric vehicle can only reach 1-2 km. An order of magnitude difference. Theoretically, batteries could go to 1000 Wh/kg some day, which…

https://ev-database.org/cheatsheet/energy-consumption-electr... The Model 3 manages < 140 Wh/km, and many seem to be under 150/160/170.

I'm at 115,000 km, at 133 Wh/km since the last (inadvertent) trip reset. The previous one (for the life of the vehicle) was at a similar number.

This is on a 2022 Long Range Model 3.

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

#494

Post by RajT88 »

fukka42 wrote: post #490
RajT88 wrote: post #406

Earlier quoted context omitted.

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. A…

Right, so they sell guns at a super market? Walmart is a super market and like you say, they sell guns. How is this "not really"?

Calling Wal-Mart a supermarket is a giant stretch. As TFA says, some Wal-marts have groceries, and some have guns, and there is some small overlap between the two, but Wal-Mart is not what anyone would call a "Supermarket" - they are more an "Everything Store" where the "Everything" can vary by location which sometimes includes guns and groceries, but always includes TV's and frozen food and fishing supplies and clothing and shoes and candy and shampoo and razors and so on...

Most people are not buying groceries there, they go to actual supermarkets - near me Jewel-Osco, Mariano's, Aldi, Whole Foods, Kroger - none of which sell guns. Grocery stores do not sell guns by any common definition of the term "grocery store". You've got a corner case off of which your talking point is built. Corner cases do not make good foundations of arguments.

My advice: Come to the US and do some grocery shopping before making more such arguments.

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

#495

Post by asynchronous13 »

danjermaus wrote: post #455
dghlsakjg wrote: post #401

Earlier quoted context omitted.

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 l…

Very curious about this because there are electric planes in testing, so how do they do it?

The existing electric planes are designed to be trainers. They are primarily for takeoff and landing and flying in the pattern at an airport. Less than 1-hour endurance, and useful load that can barely accommodate two people.

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

#496

Post by ElijahLynn »

Aurornis wrote: post #251
davedx wrote: post #6

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. YASA was founded in 2009, a spin out from Oxford University following the PhD of founder and still CTO, Dr Tim Woolmer. "Over the decades that followed both of these technologies were explored. But despite the potential for weight reduction, smaller…

> 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…

Nice observation that the weight isn't that much of a deal compared to batteries for electric vehicles!

It does seem like with this advancement, and the size of these axial flux motors that maybe, all wheel drive vehicles will be the default. As well as sub 3 second acceleration, which can make vehicles safer, for example getting out of the way of an incoming object. Of course it could also make them less safe because that vast of acceleration is kind of dangerous.

But I do wonder if the weight reduction (over 30%) of lithium sulfur batteries paired with these is really going to make a great recipe for all sorts of quiet, long lasting, powerful electric vehicles and robots!

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

#498

Post by jesse__ »

Aurornis wrote: post #251
davedx wrote: post #6

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. YASA was founded in 2009, a spin out from Oxford University following the PhD of founder and still CTO, Dr Tim Woolmer. "Over the decades that followed both of these technologies were explored. But despite the potential for weight reduction, smaller…

> 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…

Somebody's probably already pointed this out, but in the case of motors, making them lighter can make a big difference.

For example, by making the flywheel in a clutch lighter, you reduce the amount of torque it takes to spin the flywheel. Saving 10 pounds there is not a 10/3000lb difference.. it could be a huge percentage of total power output.

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

#499

Post by RajT88 »

jacquesm wrote: post #465
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…

A kid died right in front of my door on one of those. They call them fatbikes around here and they're super dangerous to operate. Way too much torque and speed for kids (and, fairly, most adults) to handle responsibly.

See - you nailed it. I did plenty of dumb shit when I was a kid, but like the specific number I quoted - 13mph - wiping out at that speed, which I have numerous times even as an adult - is a totally different level of bodily harm compared to the speeds I see kids doing on eBikes.

Would I have as a kid blasted around at 40mph if I could have? Goddamn right. That's actually my point - I'm not dead or permanently damaged, just the recipient of quite a lot of road rash. Worst injury I ever had on a bike was a broken trapezium, as an adult, for something totally not speed related (~13mph, yes), when a tree fell in front of me and I braked and flew across the handlebars. Game that out doing even 20mph and that's a different outcome.

Classic case of, "I've been there, done that, and this situation is nuts".

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

#500

Post by jacquesm »

NathanKP wrote: post #425
mywittyname wrote: post #403

Earlier quoted context omitted.

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. E…

I'm more fascinated by the question of whether it scales up... imagine much smaller and more efficient electric engines for cruise liners and cargo ships.

On a cargo ship the last thing you worry about is weight. To the point that they add ballast.
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