3 ms·

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.

• pbmonster 5mo ago
  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".
  • SoftTalker 5mo ago
    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.
    • testing22321 5mo ago
      I’ve long wondered why we don’t ditch the friction brakes. Just have the battery stop charging and report 100% full when it’s only 98% (or whatever) so there is enough capacity for some solid emergency stops in the first few minutes of driving. Even if you have to resort to the resistor, who cares? It’s not like this is a common scenario
      • OkayPhysicist 5mo ago
        That's fine, until someone charges their cabin up in Truckee and decides to drive down 80 to the central valley (a hour or so drive you can do in neutral). Regenerative braking also loses a lot of its stopping power at slow speeds. Going from "slowly rolling forward" to "full stopped" takes a lot longer than the instantaneous it is with friction brakes.
        • masklinn 5mo ago
          You also need some sort of parking brake, and friction brakes do the job nicely.