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avalys 2 days ago

Huh? What do you imagine is the tradeoff between regenerative braking and tire life? Are you suggesting that stopping the car with conventional iron brakes is somehow easier on the tires?

slt2021 2 days ago | parent [-]

the level of regenerative braking directly impacts your accelerator pedal behavior.

by reducing regeneration, you will increase tire life by virtue of modifying your acceleration behavior. Its hard for me to explain, but I just suggest trying the medium regenerative setting and you will see it yourself.

You will feel it, because the most of the tire wear happens when car decelerates. On less regeneration your car will decelerate less and will wear out tires slower

djrj477dhsnv 2 days ago | parent | next [-]

That's a whole lot of assumptions based on what?

I could come up with a list of plausible sounding reasons why regenerative braking leads to less tire wear. Unless you have some actual measurements, I wouldn't trust either one.

tbrownaw 2 days ago | parent [-]

I'm reading it as referring to a setting where the car will brake some amount (instead of coasting) if you completely let go of the pedals, and as being a claim that the commenter can't maintain speed but gets stuck in a cycle of accelerating and then letting the car brake.

Peanuts99 2 days ago | parent | next [-]

I use one peddle driving all the time and manage to keep a steady speed as I'm doing it. Why would you be constantly taking your foot off the accelerator unless you need to slow down?

I'll also throw another anecdote in for this thread, 500hp EV, 50k miles on the tyres.

djrj477dhsnv 2 days ago | parent | prev [-]

I've never driven an EV, only a hybrid a few times, but I thought for all cars with aggressive regenerative brake settings, you just kept the accelerator pedal slightly depressed to coast.

NewJazz 2 days ago | parent | prev [-]

most of the tire wear happens when car decelerates

Is this generally true? I imagine it depends on the car/driver to a certain extent, but still I'd be curious what numbers are out there.

slt2021 2 days ago | parent [-]

when car decelerates, the kinetic energy has to go somewhere, large part of it goes to battery as regeneration (60%), the rest goes to tire/road friction and wear

NewJazz 2 days ago | parent [-]

That doesn't answer my question even a little bit.

slt2021 2 days ago | parent [-]

From the physics perspective, where does kinetic energy go in E=1/2mv^2 ?

Up to 60% goes back to battery, part goes to air resistance and rolling tire resistance (can be ignored for our case as its the same regardless of regen setting), the rest goes to friction of tire/road due to slowing down tire speed

avalys 2 days ago | parent | next [-]

No one is debating that deceleration results in tire wear.

The two claims you've made are that deceleration results in more tire wear than acceleration, and that regenerative deceleration results in more tire wear than non-regenerative deceleration. These are what people are questioning you about.

slt2021 2 days ago | parent [-]

acceleration is irrelevant because you need to accelerate to move regardless.

what is relevant to prolong the tire lifetime is reducing the unnecessary tire friction against the road.

There is constant component that depends on the weight * velocity * mileage - you gonna encounter it in all scenarios

There is also a variable component that is driven by 1st derivative of speed (rate of acceleration/deceleration).

The high regeneration allows you faster acceleration/deceleration, but medium/lower will (1) change your driving behavior so that you accelerate more smoothly, and (2) change your deceleration so that you coast more and decelerate less

remember, car's kinetic energy is not a perfect energy storage, so that you could freely move energy from battery into car speed, and regenerate it back into battery.

apart from air resistance, there is 60% loss on the way back + tire wear penalty depending on accel/decel curve (1st speed derivative)

NewJazz 2 days ago | parent | prev [-]

Your claim was that most of the tire wear for cars was due to deceleration. Acceleration could be to blame too. I asked for a source for your claim, not math equations.