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0 pointsAurornis6mo ago0 comments

> It drops a buck fifty per motor. That IS a game changer.

You’re reading their marketing material. You have to think of this like all of those PR releases you’ve seen over the years about new battery technology that is 4X smaller or new hard drive tech that is 10X more efficient. The real world improvements aren’t going to be as big as their one lab test.

A Model 3 motor is already well under 150lbs, unless you start including ancillaries like the inverter and power transmission parts.

They’re not dropping “a buck fifty” from typical EV motors.

0 comments

elihu6mo ago

Nah, the main thing is that electric motors are already far better than they need to be -- even assuming the claims are all true, it would only make a small difference.

Shaving a couple percent off the total vehicle weight would still be a very good thing, but improving batter energy density by 10% or so would be a bigger deal for most EVs.

There might be some niche applications where the battery weight isn't the biggest issue -- like very short-range, light-weight vehicles that need to have enormous amounts of power for some reason.

I could see motors like this being used in power tools if they can be scaled down. A light-weight plug-in electric chainsaw would be pretty awesome.

nandomrumber6mo ago

> A light-weight plug-in electric chainsaw would be pretty awesome.

These already exist, in both plug-in and cordless / battery powered.

elihu6mo ago

Small wimpy ones are widely available. I'd love to have an electric chainsaw that runs on 220v and has a respectably long bar, but those don't seem to be available in the US as far as I can tell.

At 30 amps and 220 volts, that would be about 8 horsepower. I think most motors that size rated for that much continuous power would be rather heavy.

catapart6mo ago

I'm not reading anyone's marketing material. If you want to dispute the shipping weight, feel free to correct this website whom I assume charges for shipping based on weight [0]. I'm sure they'd love to know they have it wrong.

According to purchasable equipment, the Model 3 engines weight ~175 lbs. If that's wrong, that's on them for claiming it. Subtract 28 lbs from that and you're at 147 lbs. That is very close to 150 lbs.

[0] https://evshop.eu/en/electric-motors/295-tesla-model-3-drive...

AurornisOP6mo ago

That’s a drive unit, which is more than the motor. Read the description:

> This kit includes the Tesla motor, inverter, gear box, power cables and drive shafts.

Drive shafts, gearbox, power cables, inverter. Also includes the mounts, which is likely not factored into the lab calculations for this marketing material.

You cannot drop 150lbs from the Model 3 motor because it doesn’t even weigh 150lbs.

catapart6mo ago

You're missing the forest for the trees. Dropping 10 lbs per motor is HUGE. Dropping 30 is amazing. Whatever is dropped, it's significant. Pretend that it isn't all you want, but anyone doing production work knows how important this is.

I'm happy to compare apples to apples when we can do that, and if you want me to say I was wrong about the Tesla motor size I'm happy to say that I was just going by what was available on the internet and skipped the details. But I did so in service of a point which you still haven't actually engaged with beyond "Nu uh!".

AurornisOP6mo ago

> Dropping 10 lbs per motor is HUGE.

Auto makers could drop 10lbs, 100lbs or even more from every EV right now by choosing more expensive materials, more expensive manufacturing processes, or simply cutting back on amenities.

10lbs is not significant in the grand scheme of things. The real question is how much it costs, what are the tradeoffs, and how practical is it.

> But I did so in service of a point which you still haven't actually engaged with beyond "Nu uh!".

That’s not a fair take on what I’ve been posting at all. I said every little bit helps, but pointed out that motor sizes are already small.l

2 more replies

hinkley6mo ago

Smaller motor can be one per wheel which means a shorter drive shaft, less rotating weight which means more torque to the road under acceleration and deceleration.

Tesla still doing a gearbox? Their marketing has been telling me they got rid of those. Typical.

j / k navigate · click thread line to collapse

0 comments

elihu6mo ago

Nah, the main thing is that electric motors are already far better than they need to be -- even assuming the claims are all true, it would only make a small difference.

Shaving a couple percent off the total vehicle weight would still be a very good thing, but improving batter energy density by 10% or so would be a bigger deal for most EVs.

There might be some niche applications where the battery weight isn't the biggest issue -- like very short-range, light-weight vehicles that need to have enormous amounts of power for some reason.

I could see motors like this being used in power tools if they can be scaled down. A light-weight plug-in electric chainsaw would be pretty awesome.

nandomrumber6mo ago

> A light-weight plug-in electric chainsaw would be pretty awesome.

These already exist, in both plug-in and cordless / battery powered.

elihu6mo ago

Small wimpy ones are widely available. I'd love to have an electric chainsaw that runs on 220v and has a respectably long bar, but those don't seem to be available in the US as far as I can tell.

At 30 amps and 220 volts, that would be about 8 horsepower. I think most motors that size rated for that much continuous power would be rather heavy.

catapart6mo ago

[0] https://evshop.eu/en/electric-motors/295-tesla-model-3-drive...

AurornisOP6mo ago

That’s a drive unit, which is more than the motor. Read the description:

> This kit includes the Tesla motor, inverter, gear box, power cables and drive shafts.

Drive shafts, gearbox, power cables, inverter. Also includes the mounts, which is likely not factored into the lab calculations for this marketing material.

You cannot drop 150lbs from the Model 3 motor because it doesn’t even weigh 150lbs.

catapart6mo ago

AurornisOP6mo ago

> Dropping 10 lbs per motor is HUGE.

Auto makers could drop 10lbs, 100lbs or even more from every EV right now by choosing more expensive materials, more expensive manufacturing processes, or simply cutting back on amenities.

10lbs is not significant in the grand scheme of things. The real question is how much it costs, what are the tradeoffs, and how practical is it.

> But I did so in service of a point which you still haven't actually engaged with beyond "Nu uh!".

That’s not a fair take on what I’ve been posting at all. I said every little bit helps, but pointed out that motor sizes are already small.l

2 more replies

hinkley6mo ago

Smaller motor can be one per wheel which means a shorter drive shaft, less rotating weight which means more torque to the road under acceleration and deceleration.

Tesla still doing a gearbox? Their marketing has been telling me they got rid of those. Typical.

j / k navigate · click thread line to collapse