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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

#271

Post by VikingCoder »

floo wrote: post #177
fainpul wrote: post #149

Earlier quoted context omitted.

> 59kW/kg At this point why don't we get rid of the k prefix and write 59W/g? Edit: I was half joking, but various answers mention kW being standard for motors, kg being the SI unit for mass etc. All true, but as used here in a combined unit, which means "power density" it still would make sense IMO. It's not like the "59" tells you that it's a strong motor and hence you want kW to compare it to other motors. You can…

Because kg is the fundamental unit of mass and kW is typically used for electric motors. Same reason you wouldn't use m²/s³ even though that's also technically correct.

If "kg" is the fundamental unit of mass, then honestly, why isn't a gram referred to as a "millikilogram"?

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

#272

Post by jabl »

throw-qqqqq wrote: post #187
mort96 wrote: post #53

Earlier quoted context omitted.

Range being worse with a fully loaded car than with a lightly loaded car isn't exactly news, and not exactly limited to electric cars. I can clearly feel my old diesel struggling more when I'm driving 3 friends and with loads of heavy stuff in the back than when I'm alone. That makes the gas bill more expensive.

You probably know already, but ICE cars only convert about 20–30% of fuel energy into motion, while EVs are often +90% efficient. So when an EV has to work harder (extra battery weight or colder weather), you notice the drop in range more. In an ICE, the same load is less visible because most energy gets wasted as heat. This is also why cold weather seems to affect EV range more.

> You probably know already, but ICE cars only convert about 20–30% of fuel energy into motion, while EVs are often +90% efficient. So when an EV has to work harder (extra battery weight or colder weather), you notice the drop in range more.

There's a kernel of truth here in that Otto engines suffer lower efficiency at part load, however I suspect the real reason is that gas car range is "good enough" and refilling is fast, so one doesn't tend to obsess about remaining range.

> This is also why cold weather seems to affect EV range more.

That's because a) some batteries suffer degraded performance at low temperature, and b) ICE cars use the plentiful waste heat for cabin heating whereas an EV needs a heat pump or even resistive heating of the cabin air.

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

#274

Post by DrScientist »

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.

I'm not an expert - but the axial flux design while old is been largely ignored due to manufacturing problems that have now been overcome ( so most of the dev has been on the radial flux variety ).

And apparently axial flux motors have shorter magnetic flux paths which reduces losses.

ie the efficiency gain is due to the switch from radial to axial flux - not some incremental gain on radial flux.

Having said that the efficiency gains are relatively small - 1-2%.

However again there is a compounding effect, in that the reduction of loss of energy as heat, leads to requiring less cooling - and/or the motor is able to operate a full efficiency over a wider power output range ( as heating the copper increases the electrical resistance ).

https://www.stanfordmagnets.com/advantages-and-disadvantages...

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

#275

Post by hedora »

linsomniac wrote: post #205
JKCalhoun wrote: post #197

Earlier quoted context omitted.

I'm more excited about light electric vehicles. (Bikes, tuk-tuks, what-have-you).

...with 1,000 horsepower. =:-)

In fairness, ICE engines have been able to provide too much horsepower for those use cases for a long time.

Cutting the motor weight probably matters more for smaller vehicles than bigger ones though.

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

#276

Post by margalabargala »

fainpul wrote: post #149
chris_overseas wrote: post #2

A link to the press release https://yasa.com/news/yasa-smashes-own-unofficial-power-dens...

> 59kW/kg At this point why don't we get rid of the k prefix and write 59W/g? Edit: I was half joking, but various answers mention kW being standard for motors, kg being the SI unit for mass etc. All true, but as used here in a combined unit, which means "power density" it still would make sense IMO. It's not like the "59" tells you that it's a strong motor and hence you want kW to compare it to other motors. You can…

It gives a sense of the functional size required.

Could the motor in question be shrunk down to 1kg, producing 59kW? Probably.

Could it be shrunk down to 1g? No.

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

#278

Post by sollewitt »

neuroelectron wrote: post #220
gwbas1c wrote: post #210

It's easy to forget that most of the weight in an electric car is the battery . It's ICE cars where a lot of the weight is in the motor. That being said, could this be adapted so that a 2.8lb motor produces 100 hp? That would allow putting a small motor in each wheel, thus completely eliminating axels, driveshafts, and allow recapturing the space they used to occupy. It also wouldn't significantly impact unsprung wei…

Is it really easy to forget?

Really easy, I've just forgotten again.

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

#279

Post by parineum »

ajuc wrote: post #225
ehnto wrote: post #221

Earlier quoted context omitted.

I agree with you however I believe weight and safety are in a complex relationship right now, which has nothing to do with performance and handling. Unfortunately I feel much less safe in a Fiat 500 when a significant portion of cars in the road weigh nearly 3 tonnes and perhaps can't even see me. I suspect most people are in SUVs because they're the pragmatic trade off between safety and convenience, not because the…

Tax SUVs out of existence.

Ironically, they've been taxed into existence.

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

#280

Post by mattmaroon »

thelastgallon wrote: post #131
mattmaroon wrote: post #117

Earlier quoted context omitted.

Huh? Britons get locked up for social media posts. Most of the world doesn’t have guns. And among the first world we’re the only ones free to go bankrupt from medical bills! Our problems don’t stem from lack of freedom, they stem from too much of it.

> Most of the world doesn’t have guns. No guns, but they have solar panels, batteries, EVs, etc.

You have the sort of view of America that I can only imagine comes from somebody who has never been here. I don’t know what you mean by batteries, I’m not aware of any we don’t have available.

We have the second most electric vehicles after China, and nearly all new power generation being built here is renewable. I’m not sure how you managed to turn this into some anti-American rant, but at least do a better job of it, it’s very easy.

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