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The guide to real-world EV battery health

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Re: The guide to real-world EV battery health

#81

Post by bluGill »

dangus wrote: post #8
epistasis wrote: post #6

Earlier quoted context omitted.

That's absolutely untrue. The majority of the environmental damage is from the ongoing use of it, not from production. Every time you fill up on 20 gallons of gas, that is 400 pounds of CO2 that will be dumped into the air. Used EVs are apparently very cheap. Most new cars are prohibitively expensive, the average new car cost is something like $50k now in the US. If anybody is concerned about cost of new cars, they a…

To add to this, almost nobody statistically keeps their vehicle very long. People keeping a car for 20-30 years is extremely rare. The median length of car ownership is something like 7 years. Even if you are switching between used cars, most people are switching vehicles at some point. From what I understand even considering battery mining and using dirty electrical generation, you’re still at breakeven within a cou…

New cars are typically on a 3 year lease - a lot of people must be keeping cars for a long time to bring the average to 7

Re: The guide to real-world EV battery health

#82

Post by bluGill »

graemep wrote: post #64
303uru wrote: post #48

Earlier quoted context omitted.

Bike is the most efficient form of transportation, even walking doesn’t compare.

I want to get more exercise. Therefore I should walk rather than bike.

This is about transportation. Walking doesn't get you far. A bike uses similear energy but you get farther.

Re: The guide to real-world EV battery health

#83

Post by bluGill »

hdgvhicv wrote: post #21
cogman10 wrote: post #7

Earlier quoted context omitted.

Bike > walk == public transit > used EV > new EV > used ICE > new ICE That's pretty much the order of "greenness" in personal transport. New EVs will pay off their added carbon footprint in roughly 1 or 2 years in most locations. The ultimate determining factor of how fast that is the energy mix of your local power generation. The only time it'd probably be better to continue using an ICE is if that ICE is a moped or…

My small car does 3,000 miles a year, or 300 litres of petrol a year, or about 1 ton of co2 a year. How many co2 tons are generated in making a new Nissan leaf?

I kept my last car for almost 20 years for that reason, but parts were rusting off - the fuel tank fell off was what made me give up. At this point that car is scrap and I am in a newer car that is made no matter what, so that co2 is a given.

Re: The guide to real-world EV battery health

#84

Post by tbrownaw »

oklahomasports wrote: post #20

81% of original capacity for many cars means when driving at highway speeds you will get like 250 miles or less range per charge. Still dramatically less than gas cars.

> get like 250 miles or less range per charge. Still dramatically less than gas cars.

My old '07 Focus would get about 260 or so miles between visits to the gas station.

Re: The guide to real-world EV battery health

#85

Post by beAbU »

tbrownaw wrote: post #36
nritchie wrote: post #9

Hopefully, in coming years, we will see more practically designed EVs that are more affordable. A practical car doesn't need neck-snapping acceleration, every bell-and-whistle and room for a family of six with a dog. I'd like to believe that as batteries cost drop, the incentive to justify the extra cost will drop. Then we can get back to "just basic transportation" rather than a luxury product for the rich. While $3…

> doesn't need neck-snapping acceleration I thought this was mostly* a side-effect of electric motors inherently behaving differently than combustion motors. * Not that it can't be deliberately turned off since everything goes through a computer.

My 2019 Hyundai Kona has a 150kw FWD motor. I love my car, but it's power is totally and utterly stupid. I can spin my wheels while going 60km/h and flooring it. It can be downright dangerous in the wet. Thank dog for traction control I need to drive it in 'eco' mode most of the time in order to make the ride feel sane.

I think a motor with half the output would still result in a great ride, but the car would've been cheaper/lighter.

Newer EV's come out with much smaller motors it seems, which makes sense to me.

Re: The guide to real-world EV battery health

#86

Post by beAbU »

bryanlarsen wrote: post #67
margalabargala wrote: post #59

Earlier quoted context omitted.

There are two different factors here. One, as you noted, is that electric motors can apply full torque from a stop, increasing perceived acceleration. The other, and more impactful, is that electric motor power scales with cost much more cheaply than gas motors, so vehicles will oversize their electric motors.

There's a third factor. Ev's need to support fast charging. So they need to do support super high voltages and currents. That's much of the expense of a powerful EV. A powerful motor is relatively inexpensive in comparison. If you can charge a car in 20 minutes, the battery and some other circuitry can support discharging in 20 minutes, which is an insane power level.

A powerful motor needs more copper between the battery and motor and more silicon in the inverter to handle the current. The motor is also heavier. This is all extra cost.

All that fast DC charging requires are cells capable of handling the current.

You don't get a powerful motor for free just because you can fast charge.

Re: The guide to real-world EV battery health

#87

Post by cogman10 »

closewith wrote: post #75
cogman10 wrote: post #74

Earlier quoted context omitted.

> That's to break even with a new ICE. No, that's to break even with a new EV per the article I posted. I'd love to see a source that says otherwise. I think you have a bad source for the CO2 emissions of new EV production.

From the ICCT, ironically under the subtitle "Addressing misuse of data in the EV debate": > One common claim is that electric vehicles have higher emissions associated with battery manufacturing. While manufacturing emissions for battery electric cars are roughly 40% higher than for gasoline cars, the ICCT’s research shows that this initial “emissions debt” is typically offset after around 17,000 kilometers of drivi…

So I'm looking at the given graphs in your linked article and I just don't see how you are coming up with the 12 and 20 year timeframes for payback of EVs.

Just fuzzy eyeballing (I don't see the actual numbers for the manufacturing estimated CO2, just the graph), it looks like ~10% of the lifetime emissions for a new ICE come from manufacturing. That would put the the new EV payback vs used ICE at 4 or 5 years.

At that point, it just sort of depends on how long you hold onto your ICE for.

Re: The guide to real-world EV battery health

#88

Post by margalabargala »

bryanlarsen wrote: post #78
margalabargala wrote: post #76

Earlier quoted context omitted.

That's not exactly true. There is some shared wiring between the DC fast charger and the motors, but not so much that the powerful motors are "free". The wires that run between the motors and the battery are long. I think the larger third factor is regenerative braking. That uses the exact same circuitry as powering the motors, and if you want to be able to brake quickly without the brake pads, that's a lot of kW to…

There's a reason I emphasized the battery in my comment. :)

Got it, I skimmed that part the first time I read it. We're on the same page :)

Re: The guide to real-world EV battery health

#89

Post by bryanlarsen »

beAbU wrote: post #86
bryanlarsen wrote: post #67

Earlier quoted context omitted.

There's a third factor. Ev's need to support fast charging. So they need to do support super high voltages and currents. That's much of the expense of a powerful EV. A powerful motor is relatively inexpensive in comparison. If you can charge a car in 20 minutes, the battery and some other circuitry can support discharging in 20 minutes, which is an insane power level.

A powerful motor needs more copper between the battery and motor and more silicon in the inverter to handle the current. The motor is also heavier. This is all extra cost. All that fast DC charging requires are cells capable of handling the current. You don't get a powerful motor for free just because you can fast charge.

> are cells capable of handling the current.

Which is the most expensive part of an EV

Re: The guide to real-world EV battery health

#90

Post by _ea1k »

tbrownaw wrote: post #36
nritchie wrote: post #9

Hopefully, in coming years, we will see more practically designed EVs that are more affordable. A practical car doesn't need neck-snapping acceleration, every bell-and-whistle and room for a family of six with a dog. I'd like to believe that as batteries cost drop, the incentive to justify the extra cost will drop. Then we can get back to "just basic transportation" rather than a luxury product for the rich. While $3…

> doesn't need neck-snapping acceleration I thought this was mostly* a side-effect of electric motors inherently behaving differently than combustion motors. * Not that it can't be deliberately turned off since everything goes through a computer.

Yes, pretty much. The torque curve also slopes down as rpm increases, so an EV with really weak low end torque will feel really bad on the highway.

Having said that, there are some that are fairly mediocre without being completely terrible. The FWD Equinox EV as well as the FWD EV9 are acceptable to some people, but also pretty slow cars.

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