4 ms·

EVs don’t actually use the brakes much as they often have very aggressive regeneration. Rust on underused brakes is a problem on my EV at least. :-)

by Thlom 6y ago

Retric 6y ago
Also, while I can see various synthetic tires being an issue, is vulcanized natural rubber actually a problem? It’s starting off as tiny particles which should degrade fairly quickly.
- PaulDavisThe1st 6y ago
  From HN earlier today: https://www.hakaimagazine.com/features/when-rubber-hits-the-road-and-washes-away/ https://www.hakaimagazine.com/features/when-rubber-hits-the-...
  - Retric 6y ago
    The finished product isn’t considered toxic, but some individual ingredients are, including heavy metals like cadmium and lead, and high aromatic oils (more commonly known as polycyclic aromatic hydrocarbons or PAHs) So, presumably non synthetic tires are actually fine. Though, it’s not clear if that was the intent of the article.
nwah1 6y ago
Regenerative brakes rely on friction just like any other. Pollution is a given.
- durkie 6y ago
  What friction? The "regenerative" part is from the motors being driven in reverse and returning power to the battery.
  - nitrogen 6y ago
    Rolling friction in the tires / the contact patch's static friction.
    - culopatin 6y ago
      This variable is a constant between both types of brakes. How is this relevant when comparing brakes? They both need it, one puts energy into a battery, the other one just heats up air due to the friction created by the system.
      - nitrogen 6y ago
        It's relevant to the question of whether regenerative braking produces dust from tire wear.
        TheGallopedHigh 6y ago
        As compared to just straight braking — hence it’s irrelevant
        nitrogen 6y ago
        The whole thread started with this message: > Regenerative brakes rely on friction just like any other. Pollution is a given. The article is about pollution from tires. Regenerative breaking can't cheat the laws of physics. That force has to be applied to the road through tires, just like any other form of wheel braking. And tires have significantly more mass to shed over their lives than brake pads.
        deleted 6y ago
        [deleted]
    - deleted 6y ago
      [deleted]
- klyrs 6y ago
  Regenerative brakes translate kinetic energy into stored potential energy, with marginal friction and resistive losses. Friction brakes translate 100% of the kinetic energy into waste heat, through abrasion. While it's true that regenerative brakes are not frictionless, none that I'm aware of rely on friction. One could imagine using a clutch to controllably wind/unwind a spring, for example, but auto manufacturers aren't rinky-dink steampunkers and even so you'd still do everything you could to minimize clutch slippage.
  - magicalhippo 6y ago
    > While it's true that regenerative brakes are not frictionless, none that I'm aware of rely on friction. They rely on the friction between the tire and the road, wearing the tire down, releasing the microplastic particles.
    - chrisseaton 6y ago
      > They rely on the friction between the tire and the road I don't think the tire is what people mean when they talk about the brakes. They mean the brake pads and other brake components.
      - jeddy3 6y ago
        It's literally what the linked article talks about, tyre wear not break wear.
        chrisseaton 6y ago
        This thread started when someone said ‘both brakes and tyres emit pollution’. The point was the brakes don’t when they’re regenerative. I’m sure the tyres still do. But that wasn’t what the thread was about.
- chrisseaton 6y ago
  > Regenerative brakes rely on friction just like any other. I thought the resistance was provided by magnets in the motor? How do you think they capturing energy from friction?
artvark11 6y ago
Could you explain how the rust is causing an issue on your brakes? Siezed piston or pin?
- Thlom 6y ago
  It's the brake disc. Some rust on the surface is not a big problem, but if it starts digging in to the metal mass it will cause reduced brake capacity. In Europe a car with lots of rust on the brake disc will not be certified for use (mandatory checkup every two years) until the brake discs have been replaced.

EVs don’t actually use the brakes much as they often have very aggressive regeneration. Rust on underused brakes is a problem on my EV at least. :-)

by Thlom 6y ago

EVs don’t actually use the brakes much as they often have very aggressive regeneration. Rust on underused brakes is a problem on my EV at least. :-)

Retric 6y ago

Also, while I can see various synthetic tires being an issue, is vulcanized natural rubber actually a problem? It’s starting off as tiny particles which should degrade fairly quickly.

PaulDavisThe1st 6y ago
From HN earlier today: https://www.hakaimagazine.com/features/when-rubber-hits-the-road-and-washes-away/ https://www.hakaimagazine.com/features/when-rubber-hits-the-...
- Retric 6y ago
  The finished product isn’t considered toxic, but some individual ingredients are, including heavy metals like cadmium and lead, and high aromatic oils (more commonly known as polycyclic aromatic hydrocarbons or PAHs) So, presumably non synthetic tires are actually fine. Though, it’s not clear if that was the intent of the article.

nwah1 6y ago

Regenerative brakes rely on friction just like any other. Pollution is a given.

durkie 6y ago
What friction? The "regenerative" part is from the motors being driven in reverse and returning power to the battery.
- nitrogen 6y ago
  Rolling friction in the tires / the contact patch's static friction.
  - culopatin 6y ago
    This variable is a constant between both types of brakes. How is this relevant when comparing brakes? They both need it, one puts energy into a battery, the other one just heats up air due to the friction created by the system.
    - nitrogen 6y ago
      It's relevant to the question of whether regenerative braking produces dust from tire wear.
      - TheGallopedHigh 6y ago
        As compared to just straight braking — hence it’s irrelevant
        nitrogen 6y ago
        The whole thread started with this message: > Regenerative brakes rely on friction just like any other. Pollution is a given. The article is about pollution from tires. Regenerative breaking can't cheat the laws of physics. That force has to be applied to the road through tires, just like any other form of wheel braking. And tires have significantly more mass to shed over their lives than brake pads.
        deleted 6y ago
        [deleted]
  - deleted 6y ago
    [deleted]
klyrs 6y ago
Regenerative brakes translate kinetic energy into stored potential energy, with marginal friction and resistive losses. Friction brakes translate 100% of the kinetic energy into waste heat, through abrasion. While it's true that regenerative brakes are not frictionless, none that I'm aware of rely on friction. One could imagine using a clutch to controllably wind/unwind a spring, for example, but auto manufacturers aren't rinky-dink steampunkers and even so you'd still do everything you could to minimize clutch slippage.
- magicalhippo 6y ago
  > While it's true that regenerative brakes are not frictionless, none that I'm aware of rely on friction. They rely on the friction between the tire and the road, wearing the tire down, releasing the microplastic particles.
  - chrisseaton 6y ago
    > They rely on the friction between the tire and the road I don't think the tire is what people mean when they talk about the brakes. They mean the brake pads and other brake components.
    - jeddy3 6y ago
      It's literally what the linked article talks about, tyre wear not break wear.
      - chrisseaton 6y ago
        This thread started when someone said ‘both brakes and tyres emit pollution’. The point was the brakes don’t when they’re regenerative. I’m sure the tyres still do. But that wasn’t what the thread was about.
chrisseaton 6y ago
> Regenerative brakes rely on friction just like any other. I thought the resistance was provided by magnets in the motor? How do you think they capturing energy from friction?

artvark11 6y ago

Could you explain how the rust is causing an issue on your brakes? Siezed piston or pin?

Thlom 6y ago
It's the brake disc. Some rust on the surface is not a big problem, but if it starts digging in to the metal mass it will cause reduced brake capacity. In Europe a car with lots of rust on the brake disc will not be certified for use (mandatory checkup every two years) until the brake discs have been replaced.