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BMW using a brushed motor

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My first thought is, "Ah, well of course the Germans would put a wear item deep inside the powertrain that will eventually cost a fortune to replace." Curious to know what others think of this choice of technology.
 
Well, I've had one Tesla induction motor fail on me. Actually two if I count loaners, though I don't know for sure what the diagnosis was on the loaner, I suppose it could have been an electrical issue that didn't require a drive unit replacement to fix...

Still, I would rather bet on my newer Tesla's motors for long term reliability than these brushed BMW motors. Motor Trend says they asked BMW for a life expectancy of the brushes and commutators, and BMW wouldn't give one. Does BMW not know or not want to say? Either way this looks bad...
 
Well, I've had one Tesla induction motor fail on me. Actually two if I count loaners, though I don't know for sure what the diagnosis was on the loaner, I suppose it could have been an electrical issue that didn't require a drive unit replacement to fix...

Still, I would rather bet on my newer Tesla's motors for long term reliability than these brushed BMW motors. Motor Trend says they asked BMW for a life expectancy of the brushes and commutators, and BMW wouldn't give one. Does BMW not know or not want to say? Either way this looks bad...
Automotive life cycle testing typically runs 100k to 150k miles before failure depending on the component. Sometimes the only difference is the duration of the test.
 
Interesting concept. Not using rare earth minerals fits with BMW's social conscience philosophy, but brushes are maintenance items. Pros and Cons to each approach.
BMW and social conscience ... is it why it took them just over 70 years to apologies for using slave labor and supporting Nazis?
 

My first thought is, "Ah, well of course the Germans would put a wear item deep inside the powertrain that will eventually cost a fortune to replace." Curious to know what others think of this choice of technology.
Thank you. This is an interesting article. My guess, BMW is trying to find ways to produce somewhat competitive and profitable cars. The i3 was selling okay IMHO in the vacuum of the competition, but it hardly was profitable. Brush motor has two big issues - (1) obviously, lifespan and (2) heat generated at high rpms. The main advantage has nothing to do with the use of RE metals IMHO; it is in using a MUCH cheaper and easier controller. You basically can run it from your AC home power.
 
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There's nothing positive about brushed motors, Even RC cars are leaving brushed motors behind lol. In fact they are imo taking thhe movement backwards. It's already more expensive to go electric, and now they are adding more deferred pain to that equation. It's two steps forward, one back.
Right, but it just wouldn’t be a BMW if it didn’t come with some sort of design flaw that leads to very high maintenance or repair costs. I like the comment in the article that mentions how BMW keeps the brushes sealed so dust doesn’t contaminate other parts of the motor. Ah yes, just like how they do such a good job keeping oil and coolant passages sealed on their ICE powertrains?
 
Thank you. This is an interesting article. My guess, BMW is trying to find ways to produce somewhat competitive and profitable cars. The i3 was selling okay IMHO in the vacuum of the competition, but it hardly was profitable. Brush motor has two big issues - (1) obviously, lifespan and (2) heat generated at high rpms. The main advantage has nothing to do with the use of RE metals IMHO; it is in using a MUCH cheaper and easier controller. You basically can run it from your AC home power.
You missed the biggest one with respect to EVs; brush motors are less efficient than brushless ones because the brush is always in contact with the rotor, and add friction to the power train. Any gains by using brushes motors will most likely be lost by how much more batteries you will need to keep the range competitive. yeah no idea where BMW is going with this one.
 
I get that this is a Tesla echo chamber and to expect irrational negativity towards other brands, but the banter here couldn't be more uninformed. BMW's motors are 3-phase AC synchronous motors and the brush is of a slip ring design that only delivers a small DC excitation current to the rotor. It's nothing like the "DC brushed motors" that some here are using as comparison. BMW's radical new design allows for very fine control of power and torque—far more than Tesla's induction motors. BMW's design also allows for true coasting that is impossible with magnet motors.

The part in question is also located on the side of the motor that is accessible for servicing. How serviceable are Tesla's drive units? 🤣 Model S goes through an average of one motor replacement every 25,000 miles. There is something seriously wrong with Tesla's design and engineering. My impression of Tesla engineering is a room filled with farting teenagers playing video games.

BMW's magnet-free design is more resilient to supply chain issues and less reliant on China. The less anyone depends on China the better. There are no rare earth metals used in the BMW iX. To head off the poorly informed, the lithium and cobalt used in batteries are not rare earth metals. China is the #1 producer of rare earth metals used in magnets, such as neodymium.

The Tesla faithful point to a marginally faster 0-60 time for their favorite brand, but what they neglect to mention is that no Tesla has a properly designed suspension to actually handle that acceleration. The suspensions are identical whether you get the base model or the P. The only difference is the P might be a few tenths of an inch lower, which on its own does not create a performance suspension except in Tesla's imagination.

The car least capable of handling its power output is the Plaid. Try some cornering in that jalopy and you'll know what I'm talking about. It can't even hold a straight line when accelerating due to torque steer. This is due to poorly designed suspension geometry and vehicle dynamics. To get decent braking for a Plaid you have to spend $20k on upgraded brakes that other performance brands already include.

This one-time Tesla owner and fan sold his Model S and ordered a BMW iX M60. I did it over the phone with the local BMW dealer. No markup. No BS. And no reservation fee! I can no longer support a company like Tesla, where a true performance driving experience and vehicle dynamics don't even make it onto Elon's to-do list. The non-existent sound dampening and rough suspensions in Teslas should be embarrassing to all of you. Keep patting yourselves on the back for making misinformed comments.

The car ownership experience and thrill of driving encompasses far more than just a fast 0-60 time. People who value quality materials, fit and finish, build quality, and a refined driving experience will not buy a Tesla. My client dumped his Model S in favor of an Audi e-tron GT and he's never looking back. He said his Tesla was a dumpster fire by comparison. And before you take another swig of koolaid and start quoting the e-tron's EPA range, you probably had no clue that real-world range is closer to 300 miles and significantly higher than EPA rating. Tell me, how many of you have actually hit Tesla's EPA range, ever?

It might behoove some of you to open your minds. Maybe it's been so long since you've driven a properly designed vehicle that you no longer remember how that feels and sounds.