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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

#421

Post by usrusr »

MadnessASAP wrote: post #360
mperham wrote: post #356

Earlier quoted context omitted.

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.

Listen, your world may not allow you to sell an e-bike with a 1000hp motor on it. But my world allows me to put a 1000hp motor on an e-bike and not tell anyone. Now hold my beer...

So that you can flip over in an uncontrolled wheelie at an even lower fraction of the throttle? Even if there was infinite energy throughput (aka power) at zero mass, the main limiter for power per total system mass would still be the battery. In any practical setup, even in super short runtime designs, getting, say, twice the power would not all that dramatic a runtime hit if it was achieved by scaling the same motor technology and paying for the extra mass with a little battery capacity. Unless of course you want to actually use that power increase for any meaningful fraction of the runtime, then you'll obviously drain the battery fast. But a zero-mass power increase would not change that a lot either.

Increasing power density (of the motor) just isn't worth much when it does not happen to coincide with an increase in efficiency (and then the battery mass saved for achieving the same range will quite literally outweigh the mass saved by a smaller engine for achieving the same power)

The good news is that those striving for power density aren't really at liberty to completely ignore efficiency in the process because cooling is a key issue for them.

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

#422

Post by murkt »

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.

That’s still around 2 km per kg of batteries.

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

#423

Post by dralley »

hinkley wrote: post #350

First motor I saw in this category was much larger because it had massive mount points to attach it to the car so the torque would go to the wheels and not to destroying the motor. This one has a narrow ring meant for 3/8” bolts? I guess if you’re buying a 1000 hp motor you can afford titanium carriage bolts.

I suspect this may end up in Mercedes Formula 1 power units, so that may not be off-base. Use whatever ridiculous materials you can to keep the weight and size down.

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

#424

Post by lunias »

hinkley wrote: post #377
testdelacc1 wrote: post #285

Earlier quoted context omitted.

Your intuition is correct. Americans’ Love Affair with Big Cars is Killing Them ( https://www.economist.com/interactive/united-states/2024/08/... ) - The Economist. > In a crash, the fatality rate of the occupants of the heavy pickup truck is about half that of the compact car. But they are also far more dangerous to the fatality rate of people in other cars. > The fatality rate is roughly seven times higher when col…

Well, hood and grill shapes are mandated for pedestrian safety but everyone else is fucked.

If a pedestrian gets hit by a tall vehicle, where the bumper is at waist level or above, then the pedestrian goes under the vehicle. This is what causes most of the fatalities these days. Breaking your legs is bad, but getting run over is the end.

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

#425

Post by NathanKP »

mywittyname wrote: post #403
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…

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.

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

#426

Post by xandrius »

mrguyorama wrote: post #338
xandrius wrote: post #99

Earlier quoted context omitted.

I don't think it's fair to insult all US citizens because of your personal shortcomings.

No, Americans are numerically illiterate. Which is why all the dumbest Americans insist that "Why didn't they teach us how to balance a check book?", while, well, they were taught that , and every single check book comes with clear and simple instructions for its use They were also taught how to calculate loan details and the extreme power of how interest grows, but they were too busy crying "Oh this is lame, when am…

Sorry for the ignorance, what what does "balancing a check book" mean? Is that an euphemism or an actual activity?

I can of course look up but interested in continuing the conversation.

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

#429

Post by hshdhdhehd »

superxpro12 wrote: post #213
FabHK wrote: post #8

Outperformance metric is basically power density. The model described is some 13 kg and delivers 750 kW peak, 350+ kW sustained. (That's 28 pounds, 1000 hp peak, 470+ hp sustained.) The 40% improvement is actually 36% and is versus the previous model of the same company.

Peak power is a number that can be manipulated. You just dump short circuit current into a winding. Even if that peak lasts for 1 microsecond, you can "claim" eye-watering horsepower numbers. I wonder if we defined peak as sustained peak over 100 milliseconds, or some more meaningful number, what that would do to the claims. You aren't really generating meaningful torque over 1 microsecond.

Surely they measure output not input?

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

#430

Post by bootlooped »

SR2Z wrote: post #385
mperham wrote: post #356

Earlier quoted context omitted.

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.

They are not allowed, but still commonly owned and used. The law needs to catch up. There are clearly good reasons for people to want extremely powerful e-bikes and they should be allowed to. They can't be treated like bicycles because they're too fast but aren't nearly as dangerous as motorcycles. We need a new category for light motorcycles. The real problem, IMO, is that the law is generally not deferential enough…

> The law needs to catch up. There are clearly good reasons for people to want extremely powerful e-bikes and they should be allowed to.

I'm not so sure about that.

I don't want a 6000kw Sur Ron riding in the bike lane with me. The whole point of the bike lane was to make a safe space for riding a bicycle. I want the bike lanes to be safe enough for children to ride their bikes in, and having something that powerful in it is not conducive to that goal. They are by and large too fast and too unlike a bicycle for bike lanes. Having things that powerful there is going to dissuade a lot of potential (non electric) cyclists. My girlfriend already gets too freaked out by how fast some of the legal e-bikes in the bike lane go.

Certainly they shouldn't be on the sidewalk. But what does that leave? Just the road. If that's the case they probably need to just adhere to whatever standards the state has for scooters or mopeds. Which probably means some kind of license, maybe registration, and possibly insurance.

But that type of e-bike manufacturer doesn't want to make a light electric scooter that's road legal, they want to make a thing that skirts regulations by being "for off road use only".

And the buyers by and large don't want to deal with license and registration, and certainly not insurance.

Just because people are doing an illegal thing a lot doesn't mean that the law needs to find a way to make it legal.

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