[omnomynous]

Regen braking is extremely weak and takes a much longer distance than you'd imagine to bring the car to a complete stop. The best use-case for it is slowing from high speeds to moderate speeds, whereby the deceleration is greatest and the recharging is most powerful. For instance, imagine exiting an 80 mph highway onto a 40 mph access road. It's worth noting that the rate of deceleration on regen brakes decreases as the speed approaches zero, rather than the reverse as with non-thermally-overloaded friction brakes. Fundamentally, this occurs for the same reason that stopping a given car from 120 mph takes more than twice the distance compared to stopping the same car from 60 mph - part of the equation of calculating the kinetic energy (what's powering regen brakes) of a moving vehicle involves squaring the speed of the vehicle. With this in mind, braking duty cycle of a typical urban or suburban mail truck (which does a lot more 25-0 than 80-40), is pretty much the worst possible duty cycle for use alongside regen brakes - you are getting almost no energy back and almost no braking force in this specific duty cycle.

[stetrain]

Have you driven an EV with “one-pedal-driving”?

I agree that the regen efficiency is reduced at lower speeds, but many EVs are perfectly capable of coming to a stop quickly on regen and only apply the friction brakes right at the end of the stop.

[omnomynous]

I have, I owned a Tesla Model S P85D for a while. Had to turn off one-pedal-driving. I found it substantially less intuitive than two pedals for any kind of spirited driving, which is what I do every time I get in I car I own. I've had 5 corvettes, 3 GT-R's, and currently driving an 800 hp Mercedes AMG GT S (2 door coupe, not that horrid 4-door atrocity), so I'm admittedly not the target demographic either for one-pedal-driving or EV's more broadly, as they currently stand.

My standards for what qualifies as "strong" braking are probably bordering on alien for most people, too - about 95 feet for 60 mph to 0. That Tesla took almost 120 feet. A new Honda Accord takes about 130 feet.

[stetrain]

Did the P85D actually come to a full stop via regen? I thought that was only a feature of newer Tesla models. The newer models are certainly capable of stopping using the motor alone, you can feel the friction brakes engage to hold you at a stop.

Edit: https://www.greencarfuture.com/electric/tesla-one-pedal-driv...

[omnomynous]

It would not, but it did bring it down to a crawl of maybe 3-5 mph.

[stetrain]

Newer models have much stronger regen all the way down to 0mph.

The main issue with relying on regen is reduced regen power when the battery is cold. For a mail truck I think a stronger battery heater while plugged in, or a braking resistor to turn regen power into battery heat, would be helpful.