Teslas turn off regenerative breaking if you charge too far, but the car tells you that pretty prominently: however, the car handles very differently without Regen brakes.
Why can’t Tesla just give us an option to keep it consistent? I guess adding video games is more important.
My BMW i3 did this really well, FWIW.
Regen works because the batteries are being charged by the induction of the motors taking energy from the moving car. If the batteries are full they cannot take any more change and hence cannot draw power from the motion of the car.
What do you expect them to do? Dump the current on a giant resistor and hope it doesn't melt?
That's called an induction brake and it's already widely used in trains and semi trucks. That said, you still need a friction brake at low speeds, since the induction braking force is proportional to velocity.
You know...they could use it to boil water for a built in coffee/green tea maker.
Just a thought...
Maybe it's not worth the cost/complexity anyway, but the idea has merit somewhere in the design space.
You'd have to cool it, as other commenters have pointed out (you're putting a car's worth of kinetic energy into the thing, after all). I'm not suggesting that it's a good idea, just possible.