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Mercedes‑Benz starts large‑scale production of electric axial flux motor

media.mercedes-benz.com

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Re: Mercedes‑Benz starts large‑scale production of electric axial flux motor

#231

Post by throwway120385 »

Gracana wrote: post #144
chrisweekly wrote: post #81

Earlier quoted context omitted.

In terms of traction control, does this translate to something between "4WD" and "AWD"? Or is it orthogonal?

Kind of orthogonal. Traditional AWD and part-time 4WD systems are solutions to get power from a single motor to both the front and rear of a vehicle. AWD has a center differential to account for differences in front and rear driveshaft speeds when driving on high-traction surfaces. 4WD just locks the front and rear driveshaft rotation together, which is a simple and robust solution that only works on loose surfaces.…

This is probably the most succinct explanation I've ever read of the differences and the advantages of one over the other. I've been trying to understand this from different sources for years now.

Re: Mercedes‑Benz starts large‑scale production of electric axial flux motor

#232

Post by SoftTalker »

superxpro12 wrote: post #139
aitchnyu wrote: post #29

Tangential, how much regen can this system support? For example, can a car with 200kW propulsion have a 400kW regen (Tesla has upto 65) and are cost effective like friction brakes?

All motors are generators. It's only a matter of how you are creating the magnetic field with the stator windings. In order to generate a higher regen, you'd have to somehow get more energy in the motor first... and since its only rated for 200kW, good ol' physics limits you, IF thats all the energy you put into the system. If you roll it down a hill, or do something exotic like inverting the magnetic fields .... you…

You're also ultimately limited at the point where the tires lose grip and start sliding. Which can vary a lot based on road surface and conditions.

Re: Mercedes‑Benz starts large‑scale production of electric axial flux motor

#233

Post by SoftTalker »

pbmonster wrote: post #195
pjc50 wrote: post #159

Earlier quoted context omitted.

400kW regen is going to be a fairly alarming level of stopping for a normal vehicle. It's OK to leave emergencies to the friction brakes.

The idea is deleting the friction brakes entirely, saving costs, maintenance and weight. And 400kW isn't really all that much for a sports car. I remember 911 ads from the '80s that boasted "brakes with more than 1000 horse power".

So how do you stop then if the batteries are (close to) fully charged? You'd need to shunt that power into a big resistive load, and then dump that heat.

Re: Mercedes‑Benz starts large‑scale production of electric axial flux motor

#234

Post by sgt101 »

pjc50 wrote: post #153
originalvichy wrote: post #97

Earlier quoted context omitted.

I wonder how developing electric motors compares to combustion engines. My hunch says that it’s the main reason the Chinese high-tech electronics industry was able to develop and iterate leading electric vehicles so fast. (Edit: My more clarified point is regarding the machinery required + place to accommodate them to work on electric motors vs. ICE metal parts and all the intermediary parts transfering power in the…

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-wei…

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?

Re: Mercedes‑Benz starts large‑scale production of electric axial flux motor

#235

Post by tredre3 »

tw04 wrote: post #156
originalvichy wrote: post #97

Earlier quoted context omitted.

I wonder how developing electric motors compares to combustion engines. My hunch says that it’s the main reason the Chinese high-tech electronics industry was able to develop and iterate leading electric vehicles so fast. (Edit: My more clarified point is regarding the machinery required + place to accommodate them to work on electric motors vs. ICE metal parts and all the intermediary parts transfering power in the…

>I wonder how developing electric motors compares to combustion engines. My hunch says that it’s the main reason the Chinese high-tech electronics industry was able to develop and iterate leading electric vehicles so fast. The talent had very little impact to be honest. The primary factor was a government looking 50 years down the road seeing that: 1. ICE engines have little to no long-term future in transportation.…

> The US' lack of breakthroughs in EVs has little to do with technology or expertise and everything to do with an administration that is openly hostile towards EVs and renewable energy in general.

It has nothing to do with the current administration either. For one thing, China's dominance predates it. For another, the EU and Japan have failed equally hard at capturing any meaningful EV marketshare.

Re: Mercedes‑Benz starts large‑scale production of electric axial flux motor

#237

Post by zardo »

klaff wrote: post #175
0-_-0 wrote: post #131

Earlier quoted context omitted.

No, it means the motor is smaller and it can be put into the wheel

It doesn't make that a good idea. Armature losses are proportional to torque squared - doesn't matter if it is radial or axial design. That's why all the EVs today have gear boxes with ratios like 13:1. Get rid of that gearbox and the steady-state losses go up with the square of that ratio. Then there are the issues of sprung mass, and where to put the mechanical brakes.

YASA claims their integrated brake/wheel motor is lighter than comparable (supercar) disc brake systems.

Re: Mercedes‑Benz starts large‑scale production of electric axial flux motor

#238

Post by ajuc »

FabHK wrote: post #212
j_maffe wrote: post #209

Earlier quoted context omitted.

I think the cited weight loss comes from energy efficiency gains leading to less battery capacity needed.

Electric engines are already very efficient (particularly compared to internal combustion). If you go from 90% to 95% efficiency, you don't save much in terms of battery. ETA: Internal combustion engines half a century ago had an efficiency of 20%, now they're at 40%. That cuts the fuel you need to carry in half. Electric engines are near 100%, and as I said, going from 90% to 95% efficiency cuts required battery by…

Going from 90% to 95% efficiency you're halving the thermal loses, thus reducing the need for cooling by half. It's a big deal.

Same with going from 99% to 99.5% efficiency. It still reduces the cooling needed by half.

Re: Mercedes‑Benz starts large‑scale production of electric axial flux motor

#240

Post by WillAdams »

ardit33 wrote: post #198
tclancy wrote: post #126

Earlier quoted context omitted.

Every plausibly cool electric car innovation leads me to the same thought: “5-10 years from now, the restomod potential will be wild once these come down in cost.” For this, I am imagining retrofitting a Pontiac Fiero to reduce as much weight as possible and see if extended flight becomes possible.

Number 1 problem is battery weight though. Not electric motors. I have a 84 w123 300D, and would love to add some more power to it. Lightweight hub motors would be great, but any decent size battery would be at least 200lbs+, which is hard to do on a old chasy.

Jeep/Stellantis certainly had problems trying to do this:

https://www.thedrive.com/news/jeep-tells-4xe-hybrid-owners-t...

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