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Comment by nabla9 | Hacker News Reader

Tires and brakes. With EV's this gets relatively worse because they are heavier.

Minus brakes on EVs. They usually do not use their break pads.

ehhh, they certainly can and do... but I think there's a case to be made that this can be lower when managed appropriately

My only experience is BMW EV, but my i4 aggressively prioritizes regeneration over using the brakes. It even has an energy meter that shows negative/positive energy flow. The positive flow is blue until the actual brakes engage where it changes to black. And this is in two pedal mode, one pedal driving is even more aggressive about regen.

I would not doubt I use my breaks 1/20th of the amount that our X5 or Silverado use theirs.

It varies by model, I know some lower end EVs from GM still use the breaks quite often depending on the driving mode.

I have an Equinox EV and the brakes do not get used often. They did a great job with blending kinetic regeneration with friction activation, but you can still feel the difference when it kicks in.

They are active in reverse, to ensure that they are used and so that any rust gets cleared from the rotors. They also activate if you slam on the brakes or if the battery is at 100% charge and the kinetic energy can not be used.

I have about 12,000 miles on the car over the last year and the rotors and pads look the same as when I got them. The first annual inspection showed no measurable wear.

I've rented a Chevy Bolt before and in the normal drive mode (D) the brakes almost always get used in addition to light regen. In the single-peddle mode (P) regen is prioritized a lot more but passengers complained about not liking the feel versus standard braking.

Blending brake with regen is normal to avoid rust to develop on the rotor but I haven’t seen any EV that don’t prioritize regen over normal braking.

They can, obviously, but it is done very very sparingly.

EV's almost never use brakes, and the weight difference isn't really that much. A base trim model 3 is less than 10% heavier than a base trim Camry.

https://www.truecar.com/compare/tesla-model-3_standard-vs-to...

But the tires are individually controlled - less slippage - and the brakes are regenerative. As a bonus, NYC is pretty much best-case scenario for the latter.

While this is generally true, tire wear is known to be generally faster on EVs due to their weight and instantaneous torque when accelerating.

Which, as an EV owner, feels like an "oh no, my steak is too buttery" kind of problem to have.

The instant torque also comes with better control over it, though. I don't doubt it's a thing, but I do doubt it outweighs all the other environmental benefits.

It’s the forces that accelerate the wear. Significant wheel speed is a rare occurrence in normal driving, but acceleration, cornering, and braking forces are ever present.

> But the tires are individually controlled - less slippage

Not relevant for normal driving. The tires aren’t spinning appreciably due to acceleration except in brief moments with aggressive driving.

EVs can actually have higher acceleration related tire wear because they weigh more and have more instant torque on demand.

A lot of consumer EVs have filtered throttle pedal inputs to reduce the torque spikes though.

Not all tire wear is when skidding out. A car tire's contact patch is several inches wide (especially on trucks/SUVs where extra-wide tires are often used to give a more premium look), so any time that wheel is turning a corner, there's a portion of it at the outside and inside that's rotating at a different speed than the pavement beneath it is moving.

There's also the regular deformation of wheel just in the course of regular rotation, which is where the majority of highway wear dust comes from.

With extea weight and tire size, evs will have more slippage. It isnt about the entire tire slipping against the ground. It is about tread patterns slipping as the tire rolls at any speed, especially in corners where car tires cannot ever avoid slipping.

My Polestar 2 (shared design from Volvo's EVs) only uses brakes once it's hit its regen limit, this changes based on battery capacity and temperature but in the real world it means coming to a near complete stop from 50-60mph. The constant rust on the brakes are evident to that.

And you gotta have soft tires to harness that EV torque people expect. Not like the old days where they put hard stiff tires on Priuses to wring out every MPG.

https://electrek.co/2025/05/27/another-way-electric-cars-cle...

TLDR regenerative braking reduces this significantly, nut getting the raw numbers is always fraught with today's horrific AI-addled search engines.

Also seems like a wonderful opportunity for the materials science people to print money coming up with better brake materials here. And if anyone here who can say "clean coal" with a straight face disagrees, point and laugh at them.

Edit: Uh Oh! Facts...

Whoops

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