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0 pointspjc5016d ago0 comments

The Chinese EV industry is actually lead by development of batteries, especially CATL. Along with the pack engineering, which is good old Mech.E stuff about heat transfer and physical strength.

Secondarily power electronics; at that scale, you can't just pick a bigger transistor and call it a day.

By comparison the motors seem to be a mostly solved problem, although I'm sure there's still some scope for power-to-weight engineering there, it's not as critical as the battery pack.

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7 comments · 3 top-level

DrBazza16d ago· 3 in thread

And is development of batteries (and better magnetics) not just chemical engineering and material science?

Motors might be a 'solved problem' - there might not be much innovation, Maxwell's laws aren't changing any time soon, but there will surely be a lot of incremental improvement - an early 1900s ICE is considerably worse than a 2000s ICE.

bluGill16d ago

> n early 1900s ICE is considerably worse than a 2000s ICE.

But how much worse is a early 1900s electric motor from a modern one? I can't find data, but I suspect the first electric motor from the 1830s is more efficient than a modern ICE (even if we assume the ICE is built for efficiency, screw emissions). There is some room for improvement, but there isn't much difference between our best motors and perfection (a carnot cycle by contrast is as best much worse than perfection)

crote16d ago

Early electric motors were awful, because there was no good way to control their speed.

For example, DC motors used in some late-1900s trains still had a giant variable resistor in series with their motor, burning away a huge chunk of the power as heat to force the motor to run at a lower speed during acceleration. AC motors weren't much better.

Electric motors only became truly efficient when variable-frequency drive became viable, which was in the 1980s due to semiconductor innovation.

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lazide16d ago

Helped along by the somewhat Wild West attitude towards worker safety and industrial regulation - high energy density batteries are hard to get right, and extremely dangerous if done wrong. During manufacturing in particular.

And only get cheap at scale.

ajross16d ago· 1 in thread

> The Chinese EV industry is actually lead by development of batteries

This is the core point, but it applies for the whole of the industry. Motors just don't matter. An electric motor is an almost vanishing component of the weight and complexity of an electric vehicle. Cut the mass of the thing *in half* and you're looking at 100kg savings, tops. You could do that with a Model Y by just changing the roof material to something boring and not glass. You could almost do it by shrinking the oversized-as-is-the-fashion wheels.

So... it's great that Mercedez-Benz is producing these, I guess. But it won't make their cars anything more than incrementally better. Which is why we're seeing them crow about it in a press release and not a spec sheet.

dcrazy16d ago

If they’re small, light, and cheap, you can put 4 of them on the car and get independent all-wheel drive and insane acceleration.

We have a dual-motor EV and our lease is expiring this year. We have our eyes on the GLC EV, which will land in the U.S. with a tri-motor design at first. There’s no fun in a single-motor EV.

sgt10116d ago

I thought that for a long time the german supply chain had an advantage in terms of the precision engineering to create drive chains for ICE - but EV's don't have the same number of moving parts and hence... end of advantage?

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