Electric motors with no rare earths • Hacker News Board

Re: Electric motors with no rare earths

#101

Post by bgarbiak » Sat, Jun 13, 2026, 6:54 AM UTC

tencentshill wrote: post #91

PedroBatista wrote: post #11

Earlier quoted context omitted.

The cheapest EV model Renault sells is around €20K, the cheapest BMW EV is around €65K. It's safe to say the companies are not in the market bracket, no?

BMW also produces Mini EVs, which start at £26,840

The cheapest Minis are made by GWM in China, and are using different motors and batteries.

However, comparing prices between cars nowadays is a complicated matter. BMW's iX1 and iX2 (they use the BMW EESM motors) theoretically cost about €55k, but they have been very recently available to lease for about €250 euro per month - so pretty much for the same price as the cheapest electric Renault if leased.

Re: Electric motors with no rare earths

#102

Post by nandomrumber » Sat, Jun 13, 2026, 6:56 AM UTC

throwaway2037 wrote: post #99

lostlogin wrote: post #41

Earlier quoted context omitted.

The bit the gets me more than the sale price is servicing. BMWs have a terrible record for needing expensive repairs. I know you shouldn’t rely on anecdote, but it seems I do.

> BMWs have a terrible record for needing expensive repairs. EVs? That makes no sense. EVs are so much simpler to maintain compared to ICEs.

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Re: Electric motors with no rare earths

#103

Post by nandomrumber » Sat, Jun 13, 2026, 6:58 AM UTC

irishcoffee wrote: post #85

scheme271 wrote: post #82

Earlier quoted context omitted.

It's more than that though. Any repairs due to wear and tear or whatever, ends up being really expensive. Although you can probably reduce the costs a bit if you get the non-branded OEM part or potentially the same part from another manufacturer (e.g. the toyota supra uses a lot of bmw parts so if the toyota part might be cheaper than the same bmw part).

That was my whole point actually, the wear and tear is really minimal if you get regular oil changes. Things don’t just break and need replacing. Tires, rotors, brakes, those wear out. The tires are not cheap, rotors and pads aren’t crazy expensive and super easy to DIY. What other wear and tear things are expensive?

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Re: Electric motors with no rare earths

#104

Post by PowerElectronix » Sat, Jun 13, 2026, 7:12 AM UTC

Rare earth magnets are just too good for electric motors to go this way. Europe and the US just need to get the rare earth manufacturing going and stop being reliant on china for this stuff.

Re: Electric motors with no rare earths

#105

Post by general_error » Sat, Jun 13, 2026, 7:14 AM UTC

I own a Zoe for that reason

Re: Electric motors with no rare earths

#106

Post by regularfry » Sat, Jun 13, 2026, 7:28 AM UTC

sroussey wrote: post #92

irishcoffee wrote: post #85

Earlier quoted context omitted.

That was my whole point actually, the wear and tear is really minimal if you get regular oil changes. Things don’t just break and need replacing. Tires, rotors, brakes, those wear out. The tires are not cheap, rotors and pads aren’t crazy expensive and super easy to DIY. What other wear and tear things are expensive?

After 22 years, my z4 has needed batteries and a starter. Recently, there was a problem with the engine misfiring but it was $200. LA, California

If you had bought a 7 or 5 Series at that time, you would not have had that experience. The 2001 7 Series had something like a 25% roadside breakdown rate.

Re: Electric motors with no rare earths

#107

Post by regularfry » Sat, Jun 13, 2026, 7:36 AM UTC

hnav wrote: post #34

Jblx2 wrote: post #18

Earlier quoted context omitted.

Synchronous motors: running on software since the 1880s. Nikola really was ahead of his time!

He invented the induction motor which runs right off the grid.

Other way round. He invented the induction motor (1887) which the three-phase grid was then demonstrated to drive (1891). That's how influential it was. There are other reasons a three-phase grid is handy but being able to drive these brushless contraptions must have seemed utterly wild at the time.

Re: Electric motors with no rare earths

#108

Post by gmac » Sat, Jun 13, 2026, 7:45 AM UTC

ipbrown wrote: post #35

Electrically excited synchronous machines (EESMs), also known as wound field synchronous machines (WFSMs) have a number of potential advantages and disadvantages compared to interior permanent magnet synchronous machines (IPMSMs). IPMSMs are the dominant motor topology currently in use for North American electric vehicles. Advantages: - Not subject to the price and supply chain volatility of rare earth permanent magn…

It’s interesting that EESMs can be more efficient at high/highway speeds, and it’s something I had read before. This seems to me to be a key advantage of EESMs, because when people worry about EV range, they worry mainly about range on long-distance, high-speed journeys.

(I have a Renault EV and it’s excellent. Aside from the motor technology, it’s relatively light, has a heat pump as standard, and a good-sized battery).

Re: Electric motors with no rare earths

#109

Post by euroderf » Sat, Jun 13, 2026, 7:54 AM UTC

echoangle wrote: post #90

fragmede wrote: post #88

Earlier quoted context omitted.

there's also a plastic liner on them that I'm sure helps.

It also helps that they are made from aluminum which doesn’t rust like iron does.

And epoxy binds to aluminum just fine ? Epoxy is weird. What solid material does it NOT bond to ?

Re: Electric motors with no rare earths

#110

Post by IshKebab » Sat, Jun 13, 2026, 8:00 AM UTC

throwaway2037 wrote: post #99

lostlogin wrote: post #41

Earlier quoted context omitted.

The bit the gets me more than the sale price is servicing. BMWs have a terrible record for needing expensive repairs. I know you shouldn’t rely on anecdote, but it seems I do.

> BMWs have a terrible record for needing expensive repairs. EVs? That makes no sense. EVs are so much simpler to maintain compared to ICEs.

In theory they should be, but EVs also tend to be more computerised, proprietary and locked down than ICE cars, so in practice I think it's not as simple as that.

For example there was that case of the car that needed an entire new sealed €5k battery controller because it was in a minor crash and blew a fuse.

My garage charges 50% more for labour on EVs. I'm sure part of that is price discrimination but I bet part is also because working on them is more difficult. I would not be surprised if they need to pay more for access to the manufacturer's diagnostic tools too, which are becoming increasingly required.