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Vehicle brakes produce charged particles that may harm public health: study

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Re: Vehicle brakes produce charged particles that may harm public health: study

#61

Post by jauntywundrkind »

EForEndeavour wrote: post #37
jordanbeiber wrote: post #22

Earlier quoted context omitted.

But you rarely have to brake an EV though. I’ve had two EV’s over the last 6 years, and I have to remember to occasionally hit the brakes to keep them from rusting. One pedal driving is just money - saves power and is just much smoother over all than old school breaking. IMO.

I've never driven an EV. How do you approach stop signs and red lights other than braking? Is "engine braking" (regenerative braking?) strong enough to handle that big a fraction of slowing down in city traffic?

Recently had to learn how to force a Prius to use the brakes, as the rotors were rusting up & starting to pit!

I could not get my partner to brake hard enough to really engage the brakes. They just would not do it, would not brake hard enough to actually use the real brakes, no matter the prompting & even knowing how critical it was that we start to de-rust these rotors.

What I found out is: if you put the car in neutral, there won't be regenerative braking, & the car will use the actual brakes. That's the only way I could get my partner to use the actual brakes.

Re: Vehicle brakes produce charged particles that may harm public health: study

#62

Post by whatshisface »

varelaz wrote: post #19

Clickbait. "The toxicity and health effects of brake wear particles are largely unknown". Is there any real harm found? What's the concentration of them close to the dangerous road? What's effect of them comparing to pm10 or pm2.5?

The brake pad particles are pm10 and pm2.5.

Re: Vehicle brakes produce charged particles that may harm public health: study

#63

Post by k8sToGo »

jordanbeiber wrote: post #22
u320 wrote: post #3

Electric vehicles are heavier, which means they must spend more brake pads to stop. But they also use regenerative breaking, which reduces pad wear. So I'm not sure if they make it worse or not.

But you rarely have to brake an EV though. I’ve had two EV’s over the last 6 years, and I have to remember to occasionally hit the brakes to keep them from rusting. One pedal driving is just money - saves power and is just much smoother over all than old school breaking. IMO.

Crusing is much more efficient than one pedal driving. So it does not save power at all.

Re: Vehicle brakes produce charged particles that may harm public health: study

#64

Post by techdmn »

u320 wrote: post #3

Electric vehicles are heavier, which means they must spend more brake pads to stop. But they also use regenerative breaking, which reduces pad wear. So I'm not sure if they make it worse or not.

I drive a Tesla Model 3, a few thoughts:

* I'm hard on brakes in general, but have over 70k miles on the original pads. Regen braking reduces brake use a LOT.

* Regen does NOT bring the car to a complete stop, the brakes are blended in below something like 5 MPH. The rotors are not going to rust away, they see action every time you drive. (Some surface rust is fine and normal, EV or no.)

* EVs can be heavier than ICE cars, and most are. There are many things I dislike about Tesla, but the Model 3 is a feather weight in the category. A comparison I like to make is to the AWS Dodge Charger, which is heavier by a couple hundred pounds. I won't even talk about trucks and SUVs.

Re: Vehicle brakes produce charged particles that may harm public health: study

#65

Post by Lendal »

u320 wrote: post #3

Electric vehicles are heavier, which means they must spend more brake pads to stop. But they also use regenerative breaking, which reduces pad wear. So I'm not sure if they make it worse or not.

Good to see dozens of replies to this. Means EVs are popular.

Anyway, they're right. Brakes on EVs are normally just for emergency use. Regenerative braking (lifting up on the accelerator pedal) is all you need about 98% of the time. Traffic lights, stop signs, parking, and other such planned stops are all handled by releasing the accelerator which brings the car to a gentle stop while feeding the kinetic energy back into the battery. That's what they mean by "regenerative braking".

Re: Vehicle brakes produce charged particles that may harm public health: study

#66

Post by grecy »

varelaz wrote: post #19

Clickbait. "The toxicity and health effects of brake wear particles are largely unknown". Is there any real harm found? What's the concentration of them close to the dangerous road? What's effect of them comparing to pm10 or pm2.5?

Do you really need an independent peer-reviewed study to know if inhaling brake dust is bad for you or not?

At some point, it's important to trust your instincts. I don't think you need a medical degree to understand that inhaling tiny particles made of nasty stuff leads to bad health outcomes.

Re: Vehicle brakes produce charged particles that may harm public health: study

#67

Post by dagmx »

EForEndeavour wrote: post #37
jordanbeiber wrote: post #22

Earlier quoted context omitted.

But you rarely have to brake an EV though. I’ve had two EV’s over the last 6 years, and I have to remember to occasionally hit the brakes to keep them from rusting. One pedal driving is just money - saves power and is just much smoother over all than old school breaking. IMO.

I've never driven an EV. How do you approach stop signs and red lights other than braking? Is "engine braking" (regenerative braking?) strong enough to handle that big a fraction of slowing down in city traffic?

You just let off the accelerator. They have tuneable deceleration curves for the regenerative braking.

Think of it like playing a console game. When you hold the right trigger, your car goes faster. When you let off of it, it naturally slows down. Unless you opt in to harder difficulties, most racing games don’t make you brake much.

Driving an EV is just like that. You only really brake for an immediate stop.

Re: Vehicle brakes produce charged particles that may harm public health: study

#68

Post by losvedir »

k8sToGo wrote: post #63
jordanbeiber wrote: post #22

Earlier quoted context omitted.

But you rarely have to brake an EV though. I’ve had two EV’s over the last 6 years, and I have to remember to occasionally hit the brakes to keep them from rusting. One pedal driving is just money - saves power and is just much smoother over all than old school breaking. IMO.

Crusing is much more efficient than one pedal driving. So it does not save power at all.

Are there any cars that "cruise" (by which I assume you mean maintain velocity without applying a pedal)? Non-EVs mostly sort of do so, they still slow down gradually. I'd be interested in trying a car that cruises indefinitely. Sort of an automatic, always on cruise control.

Re: Vehicle brakes produce charged particles that may harm public health: study

#69

Post by l1tany11 »

u320 wrote: post #3

Electric vehicles are heavier, which means they must spend more brake pads to stop. But they also use regenerative breaking, which reduces pad wear. So I'm not sure if they make it worse or not.

Regen braking in most EVs is significant enough that the brake lights come on when you lift off the throttle pedal (which is what engages the regen). Tesla has said their brake pads are potentially lifetime. And for good reason. You barely use them; so much less than a normal car it’s not even close. I have a friend with a 3 approaching 100k miles and isn’t even through half a set of pads. My EV, you couldn’t even bother me to check. I already know it’s pointless.

There is a lot of variance EV to EV. Some have strong regen, some not so much. Some use 1 pedal driving, some don’t.

For instance the Porsche taycan brake pedal is setup such that the first part of the travel uses exclusively regen braking, and as you push harder it blends in more and more friction braking too. Don’t expect this to become common though, as this primarily just benefits real performance driving. Trail braking is very hard/frustrating without this kind of feature, but driving that way on the street is certainly dumb, and probably illegal (could fall under exhibition of speed?).

Re: Vehicle brakes produce charged particles that may harm public health: study

#70

Post by dunham »

EForEndeavour wrote: post #37
jordanbeiber wrote: post #22

Earlier quoted context omitted.

But you rarely have to brake an EV though. I’ve had two EV’s over the last 6 years, and I have to remember to occasionally hit the brakes to keep them from rusting. One pedal driving is just money - saves power and is just much smoother over all than old school breaking. IMO.

I've never driven an EV. How do you approach stop signs and red lights other than braking? Is "engine braking" (regenerative braking?) strong enough to handle that big a fraction of slowing down in city traffic?

In city traffic, I rarely have to break. It's basically running the motor backwards (putting a load on it) and dumping the energy back into the batteries. It's limited by how fast the batteries can accept a change, so it doesn't always work when it's very cold out. I'll have to brake when a light catches me by surprise, and I brake when backing down my steep driveway. (The car does stop before getting into the street, but it's going faster than I'm comfortable with when approaching the sidewalk.)

The regenerative breaking is applied as you let off the "gas" pedal. It's kind of like driving a stick, but slows you down faster.

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