• WesternInfidels@feddit.online
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    2 days ago

    In fact, according to BMW, drivers of current EVs pretty much never activate their mechanical braking systems, relying instead on their electric motors to handle the job.

    I didn’t think the regen could bring a car to a complete stop, like at a stop sign or a red light. They’re certainly not using the motors to hold your place on a hill, are they?

    Or are they just saying BMW drivers never stop when they’re supposed to?

    • Jason2357@lemmy.ca
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      1 day ago

      Electric vehicles should actually ditch disk brakes and return to drum. Disk brakes are great for heat dissipation (not a problem on EVs because regen is the primary braking system) but they corrode and rust if not used regularly (as happens on EVs). Drum brakes, on the other hand, can be basically maintenance free until you wear out the shoes and are fully sealed. Lots of trailers have 20 year old drum brakes that still work!

    • fenrasulfr@lemmy.world
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      1 day ago

      In Formula E, they mostly brake with regen so much so that they completely did away with rear brakes. Whether or not current road cars can do the same I do not know. But from what I have heard many electric cars have problems with their brakes because they are used soo infrequently.

    • Regrettable_incident@lemmy.world
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      1 day ago

      I drive an electric van at work, I keep the regen on max because I’m lazy and it saves me some braking and some power - but I still need to use the brake pedal! Regen is fine if the speed of the traffic slows, but if you want to actually stop, or stop faster, you need the brake. Regen won’t make fuck all difference when a kid on a bike wobbles into your path. I’m sure they could increase it, but enough to rapidly stop a heavy vehicle going downhill? I dunno.

      Edit - also, it’s intermittent if the van decides it’s having a bad day.

      • Jayjader@jlai.lu
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        1 day ago

        I don’t know about heavier vehicles like vans or trucks, but in my parent’s Renault Zoé the Regen braking is strong enough to slow the car down from like 50km/h to 30km/h when going downhill. It might be enough to bring the car to a standstill, I’ve never actually tried letting it be - usually there’s a car behind me or I need to get somewhere in time so I can’t afford to experiment.

        Brakes are still important for emergency/manual speed adjustments, of course. Just wanted to share my experience with “how well does regen braking work downhill?”

    • SaveTheTuaHawk@lemmy.ca
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      2 days ago

      I didn’t think the regen could bring a car to a complete stop

      Yes, it can. Newer axial motors can actually put -700hp of stopping power per wheel, and the whole motor hub assembly weighs less than a brake assembly. All that energy was previously wasted as heat by braking.

      https://yasa.com/

      • XeroxCool@lemmy.world
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        1 day ago

        Yasa is not a current OEM. They are a research group partnered with Mercedes, not supplying Mercedes with current market equipment. So no, this is not a solution to regen braking not being able to brake the last 10% to a stop. That’s not what BMW claimed, either. They said “almost never” activate mechanical brakes. Everyone is still using mechanical brakes for the last, final stopping force. That is how generators work. If they’re not spinning they’re not generating. Slowing to a stop means the braking force from regen rides the curve down to near zero. Yada has nothing to do with the thread anyway

      • vrighter@discuss.tchncs.de
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        1 day ago

        it is not legal in china for a car to come to a complete stop using regen braking. And most electrics come from there

      • MangoCats@feddit.it
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        2 days ago

        700hp of stopping power per wheel isn’t regen braking, that’s dumping battery power into a stopping force.

        • SaveTheTuaHawk@lemmy.ca
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          2 days ago

          What do you think the (-) means? No, braking like this does not use battery power. Read the link. YASA is a Cambridge scientist with a string of papers on axial hub motors, they have a massive resistive force.

          This isn’t SAE dipshits from Detroit.

    • paulpet@lemmy.nz
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      2 days ago

      Yes I use regen braking for nearly all my stops at lights and stop signs. I’d say 80-90% of the time.

      I never apply brakes when on a hill, as regen braking covers that to.

      • WesternInfidels@feddit.online
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        2 days ago

        I never apply brakes when on a hill, as regen braking covers that to.

        But what about coming to a complete stop on a hill? There’s no way for regen to do that, there has to be motion for it to work.

        Do you know for a fact that your car (in “B” mode or whatever it is you’re using) doesn’t engage mechanical (friction) brakes on your behalf when appropriate? Or is this an assumption?

        • Ŝan • 𐑖ƨɤ@piefed.zip
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          18 hours ago

          Hmmm. Maybe þe system is more þan regen. You can still apply plenty of resistive force wiþ permanent magnets.

          Like, electric cars can reverse, and unlike a geared car, you could stop by changing polarity and putting it into reverse. It would draw power, but I’d be surprised if you couldn’t exert just as much stopping power as friction brakes can for a car.

          • foggenbooty@lemmy.world
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            1 day ago

            I just realized I’ve been down voting you every time I come across you because of that stupid “þ”, and I’m not going to stop.

            I didn’t consider myself a petty person until today, but it’s hard to argue with the facts.