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EVs are actually phasing out both brake particle emmissions and brake fluid, by returning to "drum brakes" when regen isn't enough. https://www.continental.com

EVs are actually phasing out both brake particle emmissions and brake fluid, by returning to "drum brakes" when regen isn't enough. https://www.continental.com/en/press/studies-publications/technology-dossiers/drum-brake/ https://www.continental.com/en/press/studies-publications/te... > The drum brake offers even further attractions, the environmental particulate emissions are vastly reduced when compared to the traditional disc brake system technology, that will bring upcoming decisive decisions to comply with increasingly stricter environmental requirements. While combustion engines have had to comply with increasingly stringent emission limits in recent years, the focus has now widened to include foundation brakes. The fine brake dust generated from the brake system can have far-reaching adverse effects on human health, depending on the size of the particles emitted. Experts expect stricter legal requirements from the EU Commission by 2025 at the latest. Drum brake technology takes advantage of the enclosed housing system, allowing the brake dust particulates to be accumulated within the enclosed system that can be collected and disposed in a controlled manner that protects the environment.

lnsru 4y ago
These things rust as hell in their enclosures. Volkswagen group EVs with rear drums are catastrophic development. Take press releases and advertisement with a grain of salt next time.
- leoedin 4y ago
  Until perhaps 10 years ago, drum brakes were standard as the rear brakes of almost every car. They lasted pretty much the lifetime of the car.
  - lnsru 4y ago
    Yes. My cheap motorcycle had drum brakes and was fine for many many kilometers. The problem with electric vehicles is that they brake with motors and not with brakes. Brakes gather dust and silently corrode. Apparently latest vehicles periodically activate brakes without driver’s intervention to prevent corrosion and uneven wear.
  - jjav 4y ago
    > Until perhaps 10 years ago, drum brakes were standard as the rear brakes of almost every car. You need to go back more than that. In the 80s nearly every car had rear drum brakes, that phased out in the early 90s or so. Only the very cheapest cars had drums past that timeframe. > They lasted pretty much the lifetime of the car. Having owned a few drum braked cars (including all four wheel drums), not really. You still need to change them as they wear out, it's just a lot more work than disk brake pads which can be swapped out in a few minutes. The rear brakes do a lot less work than the fronts, particularly on smaller lightweight cars (the kind that still had rear drums in the 90s) so in that sense yes, those rear drums lasted a good while (but certainly not the life of the car). If you put front drum brakes on a fast & heavy car, you'll be wearing them out pretty quick.
    - namdnay 4y ago
      Maybe that’s specific to big US cars? Drum brakes are still completely standard on entry level european and Asian models. Rear discs only come into play when you’re going above 100hp and/or 1300kg
      - lstodd 4y ago
        Front disk brakes came into widespread use in 1960s and for a good reason. They are more efficient (read: safety) and much easier to maintain. Rear brakes are almost redundant on entry level cars except for the parking brake. You can just disconnect them and not notice any significant change in handling.
        namdnay 4y ago
        Yes, I haven’t seen front drums in at least 20 years
        jjav 4y ago
        The Honda Civic Si went to four wheel disk brakes in 1992, over 30 years ago. Last time I had to touch drum brakes was in 1991 and I'm very (very very) happy about that. Drum brakes are a maintenance nightmare I never again want to experience. I'd rather adjust carburator jets all night before working on drum brakes again.
  - deckard1 4y ago
    10 years ago? As in 2013? Did you mean 40 years ago? Almost every car? On a scale of 1 to 10 billion, how high are you right now?
    - namdnay 4y ago
      Rear drum brakes are still standarx for entry level cars in Europe. Dacia Sandero, Renault Clio, Peugeot 208 - the base models all have rear drums
  - Kirby64 4y ago
    And EVs with regen, brake usage is also vastly vastly reduced as well. Most folks aren't replacing their disc brakes in their EVs either until very high mileage unless they're hard on their cars.
- chinabot 4y ago
  running a 40 year old car (ev conversion) with drum brakes just fine. its a solved problem.
amluto 4y ago
Cute. How does the accumulated brake dust not affect braking performance? And can it tolerate getting wet inside, or is it somehow sealed well enough to go through puddles without getting wet? I suppose one could build an all-wheel-drive EV that only uses mechanical brakes during emergency maneuvers.
- sottol 4y ago
  Drum brakes have been around for a century, afaik they're more robust than discs but "lower performance". These look like a variation on a pretty standard design at first scan.
  - wlesieutre 4y ago
    Lower performance brakes is a hard trade off to make when EVs are also heavier than gas cars
    - ch_sm 4y ago
      I think the idea is that engine braking (regenerative braking) makes up for the difference.
      - wlesieutre 4y ago
        Can you rely on that if someone charges their car at elevation and then has to drive down a mountain?
        dangrossman 4y ago
        Yes, by not charging to 100%, so you have some room for additional charging by regenerative braking. Virtually all EVs come with a setting, usually enabled by default, that stops the charge at a preset percentage, like 80 or 90%. Chevy aptly calls theirs "hilltop reserve".
    - ZeroGravitas 4y ago
hedora 4y ago
EV’s greatly reduce brake wear. We live on a mountain, and typically apply the brakes for 1-2 seconds to get down with the EV. We ride the brakes for 1 or 5 minutes with our manual or automatic transmission ICE car. Put another way, we’re pushing 50K miles on the EV’s original brakes and replacing / servicing them isn’t on our radar. However, the EV eats tires like a full-size pickup truck with somewhere to be.
- yardstick 4y ago
  > However, the EV eats tires like a full-size pickup truck with somewhere to be. Out of curiosity, why is that? Edit: I Google’d: “ Electric vehicles boast instant torque, meaning they accelerate the second you put the pedal to the metal. However, the high instant torque of electric vehicles can also increase wear and tear. In addition to good grip, the rubber compound used for EV tyres also needs low rolling resistance.” And “ Teslas are heavier than most other cars because of their battery packs, which can add hundreds of pounds to the vehicle's overall weight. This extra weight puts additional strain on the tires and leads to increased friction between the tires and the road surface, which causes them to wear out faster.”
  - justsomehnguy 4y ago
    "Compared to a similar ICE vehicle" It maybe a false memory effect but I vague remember this notion about trolleybuses.
  - xbmcuser 4y ago
    While watching this video I was thinking will this solve the tyre particulates problem https://youtu.be/vSNtifE0Z2Q https://youtu.be/vSNtifE0Z2Q
    - Vecr 4y ago
      No way, the grip on a normal road with those tires would be terrible. They would also be destroyed very quickly. They are designed for off-road low-speed applications. Low rolling resistance rubber tires are much more efficient energy wise as well. Rubber tires are very advanced anyway, many use chlorobutyl blends and steel and/or Kevlar reinforments.
porkbeer 4y ago
Nobody who has ever worked on drum brakes wants to go back. Nevermind the heat and weight issues.
- jjav 4y ago
  > Nobody who has ever worked on drum brakes wants to go back. This. Drum brakes are an inordinate pain to maintain and adjust. I can change pads in disk brakes on all four wheels in less time that it took me merely to remove the drum from a single wheel in older cars.

lnsru 4y ago

These things rust as hell in their enclosures. Volkswagen group EVs with rear drums are catastrophic development. Take press releases and advertisement with a grain of salt next time.

leoedin 4y ago
Until perhaps 10 years ago, drum brakes were standard as the rear brakes of almost every car. They lasted pretty much the lifetime of the car.
- lnsru 4y ago
  Yes. My cheap motorcycle had drum brakes and was fine for many many kilometers. The problem with electric vehicles is that they brake with motors and not with brakes. Brakes gather dust and silently corrode. Apparently latest vehicles periodically activate brakes without driver’s intervention to prevent corrosion and uneven wear.
- jjav 4y ago
  > Until perhaps 10 years ago, drum brakes were standard as the rear brakes of almost every car. You need to go back more than that. In the 80s nearly every car had rear drum brakes, that phased out in the early 90s or so. Only the very cheapest cars had drums past that timeframe. > They lasted pretty much the lifetime of the car. Having owned a few drum braked cars (including all four wheel drums), not really. You still need to change them as they wear out, it's just a lot more work than disk brake pads which can be swapped out in a few minutes. The rear brakes do a lot less work than the fronts, particularly on smaller lightweight cars (the kind that still had rear drums in the 90s) so in that sense yes, those rear drums lasted a good while (but certainly not the life of the car). If you put front drum brakes on a fast & heavy car, you'll be wearing them out pretty quick.
  - namdnay 4y ago
    Maybe that’s specific to big US cars? Drum brakes are still completely standard on entry level european and Asian models. Rear discs only come into play when you’re going above 100hp and/or 1300kg
    - lstodd 4y ago
      Front disk brakes came into widespread use in 1960s and for a good reason. They are more efficient (read: safety) and much easier to maintain. Rear brakes are almost redundant on entry level cars except for the parking brake. You can just disconnect them and not notice any significant change in handling.
      - namdnay 4y ago
        Yes, I haven’t seen front drums in at least 20 years
        jjav 4y ago
        The Honda Civic Si went to four wheel disk brakes in 1992, over 30 years ago. Last time I had to touch drum brakes was in 1991 and I'm very (very very) happy about that. Drum brakes are a maintenance nightmare I never again want to experience. I'd rather adjust carburator jets all night before working on drum brakes again.
- deckard1 4y ago
  10 years ago? As in 2013? Did you mean 40 years ago? Almost every car? On a scale of 1 to 10 billion, how high are you right now?
  - namdnay 4y ago
    Rear drum brakes are still standarx for entry level cars in Europe. Dacia Sandero, Renault Clio, Peugeot 208 - the base models all have rear drums
- Kirby64 4y ago
  And EVs with regen, brake usage is also vastly vastly reduced as well. Most folks aren't replacing their disc brakes in their EVs either until very high mileage unless they're hard on their cars.
chinabot 4y ago
running a 40 year old car (ev conversion) with drum brakes just fine. its a solved problem.

amluto 4y ago

Cute. How does the accumulated brake dust not affect braking performance? And can it tolerate getting wet inside, or is it somehow sealed well enough to go through puddles without getting wet? I suppose one could build an all-wheel-drive EV that only uses mechanical brakes during emergency maneuvers.

sottol 4y ago
Drum brakes have been around for a century, afaik they're more robust than discs but "lower performance". These look like a variation on a pretty standard design at first scan.
- wlesieutre 4y ago
  Lower performance brakes is a hard trade off to make when EVs are also heavier than gas cars
  - ch_sm 4y ago
    I think the idea is that engine braking (regenerative braking) makes up for the difference.
    - wlesieutre 4y ago
      Can you rely on that if someone charges their car at elevation and then has to drive down a mountain?
      - dangrossman 4y ago
        Yes, by not charging to 100%, so you have some room for additional charging by regenerative braking. Virtually all EVs come with a setting, usually enabled by default, that stops the charge at a preset percentage, like 80 or 90%. Chevy aptly calls theirs "hilltop reserve".
  - ZeroGravitas 4y ago

hedora 4y ago

EV’s greatly reduce brake wear. We live on a mountain, and typically apply the brakes for 1-2 seconds to get down with the EV. We ride the brakes for 1 or 5 minutes with our manual or automatic transmission ICE car. Put another way, we’re pushing 50K miles on the EV’s original brakes and replacing / servicing them isn’t on our radar. However, the EV eats tires like a full-size pickup truck with somewhere to be.

yardstick 4y ago
> However, the EV eats tires like a full-size pickup truck with somewhere to be. Out of curiosity, why is that? Edit: I Google’d: “ Electric vehicles boast instant torque, meaning they accelerate the second you put the pedal to the metal. However, the high instant torque of electric vehicles can also increase wear and tear. In addition to good grip, the rubber compound used for EV tyres also needs low rolling resistance.” And “ Teslas are heavier than most other cars because of their battery packs, which can add hundreds of pounds to the vehicle's overall weight. This extra weight puts additional strain on the tires and leads to increased friction between the tires and the road surface, which causes them to wear out faster.”
- justsomehnguy 4y ago
  "Compared to a similar ICE vehicle" It maybe a false memory effect but I vague remember this notion about trolleybuses.
- xbmcuser 4y ago
  While watching this video I was thinking will this solve the tyre particulates problem https://youtu.be/vSNtifE0Z2Q https://youtu.be/vSNtifE0Z2Q
  - Vecr 4y ago
    No way, the grip on a normal road with those tires would be terrible. They would also be destroyed very quickly. They are designed for off-road low-speed applications. Low rolling resistance rubber tires are much more efficient energy wise as well. Rubber tires are very advanced anyway, many use chlorobutyl blends and steel and/or Kevlar reinforments.

porkbeer 4y ago

Nobody who has ever worked on drum brakes wants to go back. Nevermind the heat and weight issues.

jjav 4y ago
> Nobody who has ever worked on drum brakes wants to go back. This. Drum brakes are an inordinate pain to maintain and adjust. I can change pads in disk brakes on all four wheels in less time that it took me merely to remove the drum from a single wheel in older cars.