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Electric cars produce less brake dust pollution than combustion-engine cars

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Re: Electric cars produce less brake dust pollution than combustion-engine cars

#301

Post by bigfatkitten »

MindSpunk wrote: post #186
cloverich wrote: post #153

Earlier quoted context omitted.

Surprisingly you can get nearly same effect in automatics. I put around 60k miles on my first automatic (after120k+ on my first two cars, manual transmissions) and when i got my brakes checked at 63k they noted my brakes were still "brand new". I do gamify reading traffic to try and brake as little as possible (to help pass time etc), but was still surprised how far this takes you given i do plenty of stop and go tra…

It's not "nearly". It's exactly the same effect. Compression braking. Even if you're not on the throttle the engine is still rotating as it's connected to the wheels. If the engine is rotating it is compressing air. If it's compressing air but not igniting fuel (throttle closed) then it will suck energy out of the wheels to compress the air. You can do it in an automatic, you just have to force it to select a lower g…

Many modern automatics are smart enough to do this for you if you tap the brakes while rolling downhill.

Re: Electric cars produce less brake dust pollution than combustion-engine cars

#302

Post by ben_w »

ddeck wrote: post #280
ben-schaaf wrote: post #273

Earlier quoted context omitted.

They also use the electric motor(s) for braking, but instead of going into a battery it goes into a bank of resistors.

I think you meant capacitors. Resistors would just dissipate the energy as heat. edit: Thanks for the correction. They do indeed use resistors and just dump the energy as heat. Unfortunate. Hopefully this will change as supercaps continue to improve. Maxwell tech's modules are already used in light rail, and looks like some work towards smaller locomotives in Switzerland here: https://www.osti.gov/etdeweb/servlets/pu…

To add to the other comments: https://en.wikipedia.org/wiki/Dynamic_braking

Re: Electric cars produce less brake dust pollution than combustion-engine cars

#303

Post by oblio »

DataDaemon wrote: post #276

continuation of EV propaganda, which are much heavier cars.

They'll get lighter as battery tech progresses.

The first Li-Ion battery revolution has already happened, it's just not evenly distributed.

https://www.androidpolice.com/what-are-silicon-carbon-batter...

And that's before we get into stuff like solid state batteries.

10 years from now we'll probably have battery packs which are at least 20% lighter, available in some mid-range vehicles.

Re: Electric cars produce less brake dust pollution than combustion-engine cars

#304

Post by scns »

usrusr wrote: post #285
pkolaczk wrote: post #271

Earlier quoted context omitted.

Another part of the point is that you can pack a much smaller and more efficient ICE and then substitute the missing power and torque from electric motors when needed. Most cars are not used at max power all the time. You need max power only at short times when accelerating. With pure ICE there is the tradeoff - a bigger engine will get you more max power / max torque but is going to be less fuel efficient because of…

On paper, yes, but did that ever happen? Sorry for being sarcastic, but where I live the frugal hybrid is exceptionally rare and the "same big engine, but driving a much heavier car" hybrid is omnipresent. The kind of people who might buy the frugal one buy second or third hand while almost all buyers of factory new pick the "same big engine" option, and those are the ones who decide what's available on the second ha…

> did that ever happen?

In 2010 with the Chevrolet Volt.

Re: Electric cars produce less brake dust pollution than combustion-engine cars

#305

Post by Helmut10001 »

jajko wrote: post #270
Helmut10001 wrote: post #124

Earlier quoted context omitted.

I first changed the brakes on my Mitsubishi Space Star (combustion) after 13 years. It is a small car, less than 1000kg, so there is little for the brakes to do. If we produced more percentage of small cars, many environmental risks would be reduced. And btw.: The tires are now 19 years old and still good (less weight, less abrasion!).

That's not OK by any means, you don't have mandatory periodical technical inspections? This would fail immediately in any half-decent country. An example - wife's older Seat has 6 years old winter tires which were given for free when buying it second hand a year ago. Technician just told us even those are beyond acceptable here in Switzerland and we need to change them before next inspection. Your very old tires make…

We are in Germany, which has the highest inspection standards. The tires have passed every inspection. They look like new, but I will still replace them soon, just in case. I am writing this because most people cannot imagine that a 900 kg car puts very little pressure on tires, so they are hardly used.

Re: Electric cars produce less brake dust pollution than combustion-engine cars

#306

Post by cbeach »

brtkwr wrote: post #4

An an EV owner, I can testify that the tyre wear more than makes up for the reduction in brake dust. I’ve had to change tyres every 10K miles.

I think there might be something peculiar about the driving or environment. I have put 50,000 miles on my EV over the course of a few years and only changed the tires twice in that time. The car is MOT-tested every year so I have precise measurements of tread.

Re: Electric cars produce less brake dust pollution than combustion-engine cars

#307

Post by prmoustache »

dotancohen wrote: post #203
MindSpunk wrote: post #154

Earlier quoted context omitted.

You don't engine brake with the clutch, you engine brake by downshifting and using the higher engine RPM in lower gears to brake the car via wasted compression.

And that downshifting involves a clutch operation, moving the engine into a higher RPM. That most certainly wears down the clutch, talking as someone who's replaced quite a few of them.

Most of clutch wear comes from making it slip, while accelerating from a standstill.

You don't make it slip when shifting gear.

Re: Electric cars produce less brake dust pollution than combustion-engine cars

#308

Post by lotsofpulp »

mort96 wrote: post #278
pkolaczk wrote: post #271

Earlier quoted context omitted.

Another part of the point is that you can pack a much smaller and more efficient ICE and then substitute the missing power and torque from electric motors when needed. Most cars are not used at max power all the time. You need max power only at short times when accelerating. With pure ICE there is the tradeoff - a bigger engine will get you more max power / max torque but is going to be less fuel efficient because of…

And, you can make much lighter and lower range electric cars without all those heavy batteries, and boost the range with diesel when needed. Very attractive in principle. Most cars are not using their full range all the time, for a lot of people a 50 mile range car would be more than enough 98% of the time, but that remaining 2% means that people end up buying 200 mile range cars instead. But then, do you end up remo…

Smaller cars have always been available, but people have shown a preference for bigger cars where they can sit higher up, even though it costs them more.

Re: Electric cars produce less brake dust pollution than combustion-engine cars

#309

Post by rcMgD2BwE72F »

angulardragon03 wrote: post #257
PeterStuer wrote: post #230

On my non EV car I seldom use the break unless in an emergency or I have to come to a full stop. I always use the cruise control to decelerate and accelerate. Anyone else has that habit?

… how do you think the cruise control decelerates you? Is this a troll post?

Regen

Re: Electric cars produce less brake dust pollution than combustion-engine cars

#310

Post by topsecret »

mschild wrote: post #298
pkolaczk wrote: post #274

Earlier quoted context omitted.

I confirm and that’s an unpleasant surprise. Already had to replace the rear rotors and pads on my Highlander… because of rust. They should add some “brake cleaning” mode to temporarily disable regenerative braking.

> They should add some “brake cleaning” mode Also known as breaking. You could just do that once in a while.

Yup, my Golf GTE is mostly used to fetch groceries, but every now and again I'll blast down a faster road and brake harder than just regen to keep the brakes themselves in good condition. It's almost second-nature at this point.
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