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Dust from car brakes more harmful than exhaust, study finds

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Re: Dust from car brakes more harmful than exhaust, study finds

#441

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I don’t think you realise how cheap batteries are…

What? They were talking about weight. Price was not a factor.

Why is weight so important to you? It has like 10% impact to tyre wear vs how many things you'd have to sacrifice for it.

Re: Dust from car brakes more harmful than exhaust, study finds

#442

Earlier quoted context omitted.

Would love to buy a 100km range EV with easily accessible/rentable +~300km booster batteries for the occasional long drive. I guess an occasional ICE rental could fill the gap but they often nail you on long distances

That’s like saying you want a 60HP engine that you can hot swap for a 300HP engine. They’re built into the hulls!

So? Build them into removable packs

Re: Dust from car brakes more harmful than exhaust, study finds

#443
post #272
post #212

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Granted, I would still rather them designed for lighter weight. But that’s a separate issue w suv culture which is bad for society and environment in general. Totally would buy a 3000 pound EV around the size of a euro hatch.

Yes! Lighter weight would help make them safer and would help with the other big issue which is road wear.

Safer for whom? Not the occupants…

Re: Dust from car brakes more harmful than exhaust, study finds

#444

Earlier quoted context omitted.

Source for your ridiculous claim?

I'm not sure why they think regenerative breaking is worse than any other charging modality.

It's an added charge cycle on the battery. A guy in San Diego does full EIS and more for EV cells. His data shows multiple shorter recharge cycles wear the battery down faster, no matter what range you try restricting the recharging to. Same data shows that the batteries are better when conditioned harder on their first charge, gaining much better cycle performance and count, at a minimal sacrifice of capacity.

And this exact same thing coincides DIRECTLY with my lithium-powered portable lighting, so I'm pretty up-to-date on very top-level research, because I hire this same person.

His name is Luke. You'll see him all over the globe doing lithium EV research and testing.

Re: Dust from car brakes more harmful than exhaust, study finds

#445

Earlier quoted context omitted.

"It pays off to avoid this: more mileage, marginally lower charging expense, lower cost on brake maintenance and fewer complaints from passengers." Regen braking wears the hell out of your battery. That few hundred you saved on brake changes just cost you a tens of thousands of dollars on a premature battery replacement.

Really curious about this, since regen braking is Standard on all EVs

A charge cycle is a charge cycle, regardless. The wear and tear that occurs during is cumulative and doesn't just magically disappear when restricted to a certain level of battery depletion.

Re: Dust from car brakes more harmful than exhaust, study finds

#446
post #181

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I suspect drum brakes were chosen by the electron pinching EV engineers. They're the only brakes that are friction-free when not applied. Disc brakes rub (and slow the car) even when not applied.

They use drum brakes because drum brakes are protected better from the environment while brake discs are not and will quickly get covered in rust and dirt when not used for awhile and then be less effective when they are actually needed for an emergency braking situation. We only ever really went to disc brakes because they were slightly cheaper and easier to manufacture and since racing vehicles used disc brakes (be…

I've used drum brakes in older cars and motorcycles, and their stopping power is terrible, fade is terrible, and they are horrible in the rain.

The only recent cars I've had with drum brakes used them for the parking brake. They tended to corrode and not work well. Also, as an emergency brake even with a pedal you could push hard on, they were beyond terrible, even dangerously ineffective.

Re: Dust from car brakes more harmful than exhaust, study finds

#447

Earlier quoted context omitted.

I'd love one of these as an electric commuter vehicle: https://pressroom.toyota.com/album/toyota-i-road/ Unfortunately it seems to have gone nowhere

There's billions of motorcycles in the world.

On a motorcycle, I need to wear special clothes and a helmet and it's still rather unsafe.

This thing I just can get in and out like with a car. I can throw my normal backpack in there. I don't need to worry about rain. Very importantly, I at least have some material around me if someone hits me.

Re: Dust from car brakes more harmful than exhaust, study finds

#448

Earlier quoted context omitted.

Seems like EV manufacturers should set their cars to use the friction brakes for the first few stops of each trip, both to clean off the rust & dirt, and also to test whether they still work.

An electric motor is really good at arresting high rpm movement while charging, not so great at bringing low rpm movement to a stop. EVs blend together Regen and friction at slow speeds. That does wear off the rust.

> An electric motor is really good at arresting high rpm movement

I don't think any EV that I've heard of has full-range electric brakes.

There are two interesting kinds of things that I think EVs could use...

brake resistors - if the battery can't absorb the full power of regenerative braking, maybe giant resistors can take the dissipate the rest of the energy.

eddy currents - it might be cool to use eddy currents to brake.

https://en.wikipedia.org/wiki/Eddy_current_brake

Re: Dust from car brakes more harmful than exhaust, study finds

#449

> researchers grew human lung cells in a lab and exposed them to dust from car brakes and from diesel tailpipes, finding that brake dust caused greater injury to the cells. I couldn’t tell if the study found that car brakes are more harmful than exhausts, or that car brake chemicals are more harmful than exhaust fumes - but that may not be significant because they are produced in less quantities.

One other point is that brake dust is probably larger in size than particulate pollution from exhausts, and thus the nasal and breathing passage leading up to the lungs would do a better job at filtering them over more fine-sized particulate matter.

Re: Dust from car brakes more harmful than exhaust, study finds

#450

Earlier quoted context omitted.

>astroturf Is the much greater weight of EVs not worse for tire and road wear?

> much greater weight It was part of the astroturf effort to convince people that they are massively heavier, and you see it was successful with comments like this where it is claimed that they are “much greater” in weight with nothing quantified. Of course the hummer was heavier, but not everyone has the hummer. > full electric versions are only around 10% to 15% heavier than their direct ICE equivalent. https://the…

> > full electric versions are only around 10% to 15% heavier than their direct ICE equivalent.

The actual range quoted in the table at that link is 11%-17%.

> > A comparable ICE car the BMW 3 series 1570Kg - 1965Kg

Interesting that one "ICE" car can vary in weight by over 25%, or almost 400kg.

Maybe it's because that weight "range" isn't really for that ICE car. The low end of the range is suspiciously close to the 1590kg figure for the BMW 320i, an actual ICE car: https://www.bmw.co.nz/en/all-models/3-series/bmw-3-series-se...

While the upper end of the range is suspiciously close to the 1910kg of the BMW 330e -- a plug-in hybrid: https://www.bmw.co.nz/en/all-models/3-series/bmw-3-series-se...

I guess both sides can astroturf.

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