This is a terrible idea.
Braking systems need MORE redundancy. Not less.
this post was submitted on 06 May 2026
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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?
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.
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Well that sounds terrifying. There's a reason why the brake hydraulicsystem is actually two separate hydraulic systems, for diagonally opposite wheels. The only single-point-of-failure is the brake pedal.
Their leaving out the critical details on how this will electric system will be fail safe, or even legal.
The announcement was light on details about both the system itself and how its fail-safes are implemented.
Maybe they'll return to spring actuated mechanical brakes that are released when everything is working. (More common in heavy industry, and I believe also truck brakes)
Come with me on an ADHD journey!
Spring actuated, or well, any type of ‘fail closed’ brake design would definitely work.
But what happens if it fails closed (due to no power - the only failure mode I’ve considered below) and the vehicle needs to be moved?
Are they gonna do that thing they do with elevator emergency brakes with the spinning balls that engage the brakes only if a certain inertial threshold is reached? That way as long as they aren’t going too fast, the car can be pushed off the road?
Or are they gonna let you plug in a phone to charge the brake system enough to disengage the failsafe?
Maybe there will be a sweet-ass lever under the center console like the one in the first Jurassic Park movie where people have to pump it to prime the system?
My favorite iteration of this nonsensical idea is that new cars are going to come with a crank in the front, like old-school model T’s, so that in an emergency, people can wind up their cars to release the brakes.
(Please consider all of the above as me having too much time on my hands, and not a real critique of your statements. I think failsafes are a good idea. I’m just a silly.)
But what happens if it fails closed (due to no power - the only failure mode I’ve considered below) and the vehicle needs to be moved?
the same as all other cars with locked axles, they tow on a wheel sub trailer.
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What happens if it fails closed (due to no power - the only failure mode I’ve considered below) and the vehicle needs to keep moving, like on a busy highway?
Suddenly engaging all 4 wheels at maximum stopping power isn't always a safe thing to do.
Solved with ejector seats, obvs.
If you can’t physically handle explosive bolts firing within close proximity of your ears to shear the roof off your vehicle, and the subsequent 12-20G’s of acceleration as you’re unexpectedly launched skyward, then what are you even doing in a vehicle!?
As to how to trigger the explosives and rocket motors when the power has gone out? Independent emergency batteries that activate when a power loss is detected.
Could these batteries be used to power the braking system instead of a dangerous, cartoonishly violent, and ill-advised fantasy? Yes.
Will they be? No.
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So can it still stop as fast in an emergency?
Sounds like it might use back-EMF + battery energy to get a fast stop. In theory your stopping distance is usually traction limited more than brake system limited anyway.
Now, instead of overheating your rotors, you can overheat your motors.
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sir, this feature is subscription based
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