6 ms·

Electric vehicle safety via crash test

33 points by Gabriel54 2y ago

MBCook 2y ago
Maybe we should just have reasonable weight and size limits?
- bobim 2y ago
  And power limits. And bumper height compatibility. And guardrails that respect motorcyclists body integrity.
- rapjr9 2y ago
  So smaller EV batteries and less range and lower price. That seems ok to me. It's possible that advances in batteries will reduce battery weight, so replacing all the guardrails right away may not make sense. Difficult to predict battery future though. Maybe EV's need a cage at the front so the front end doesn't collapse so easily without an engine there?
yieldcrv 2y ago
Skip to 1:05 if you value your time to see the first video examples
- analog31 2y ago
  Guardrail Damage Ahead
01HNNWZ0MV43FF 2y ago
Another reason to buy a Prius > It’s not only the weight of the vehicle, TTI said. The battery used to power EVs creates a lower center of gravity and the front is a storage space instead of an engine compartment.
- tw04 2y ago
  Huh? It sounds like it's a reason to re-design the guard rails. EVs aren't going away short of the discovery of some miracle fuel that doesn't generate greenhouse gasses. Even with a 100% hybrid fleet, the emissions will still continue to exacerbate climate change. We either figure out how to stop burning oil, or mother nature will take care of the problem (us) herself.
  - userbinator 2y ago
    Where do you think the electricity to power EVs comes from?
    - dzink 2y ago
      Nuclear and Solar, at least for ours.
    - dangrossman 2y ago
      Residential rooftop solar in the US already produces enough energy to cover the charging of every EV currently on the road, and we're adding capacity each year faster than new EVs are consuming it, so that'll continue to be true.
    - Retric 2y ago
      Where do you think gasoline comes from? Even if you collected 100% of tailpipe emissions EV’s would still be cleaner in the US.
    - Schiendelman 2y ago
      Mine's almost entirely hydro.
    - Jtsummers 2y ago
      Here (central CO) our energy supply is 33% renewable (increasing each year), 35% coal (phasing out, target 2030, NM coal plants we drew from already phased out back in 2020), 18% natural gas/oil, and 14% produced by others (no direct control). The benefit of shifting the energy from gas cars to electric is that as the grid converts to increasingly focus on renewables the overall emissions drop. Many people here are also putting in rooftop solar (this is a very sunny area, even through the winter though obviously with shorter days).
wenc 2y ago
Just curious, is this an EV thing or just a high weight and low center of gravity thing? Because a number of gas cars also fall into the latter category.
- lxe 2y ago
  > The battery used to power EVs creates a lower center of gravity and the front is a storage space instead of an engine compartment. These factors can all be seen in a crash test conducted at the RELLIS Campus
  - aitchnyu 2y ago
    I cant brain the physics of both design details. Could you explain?
- nabilhat 2y ago
  In this case it's a bad test thing. The car impacted at a barrier splice which was not correctly joined. Barrier splices can come apart in the real world, but the fasteners will tear apart the sheet metal in the process. That splice gently deflected apart, like two sections of barrier were gently leaned against each other. Two posts fall over on the initial impact, one on each side of the loose splice, without causing noticable specific damage to the car. The third post absolutely caved in the front end of the car before being violently bent down underneath, as properly anchored posts do in the real world. This also isn't how this type of barrier is tested. "Barrier deflections listed below are results from crash tests with a 2,000 kg (4,400 lb) pickup truck traveling 100 km/h (62 mph), colliding with the rail at a 25-degree angle." More diverse testing done with seriousness would be a useful way to challenge if that standard continues to be appropriate, but this isn't it. https://en.wikipedia.org/wiki/Traffic_barrier#Stiffness https://en.wikipedia.org/wiki/Traffic_barrier#Stiffness
erikaww 2y ago
Couldn’t this be engineered away? Put half the battery on top and another on the bottom
- breakyerself 2y ago
  Or make guardrails better. The EV center of gravity is a plus in lots of other situations.
jader201 2y ago
The test seems to be sending the EV into the guardrail at a 45 degree angle, moving straight ahead. Is this common for guardrail collisions? Granted, it’s ideal if they can withstand that angle of impact, but I’m trying to understand the real world impact to safety this has.
- esjeon 2y ago
  Fairly common. A lot of things can happen during accidents, and cars sometimes run into guardrails at angles greater than 45 deg.
  - jader201 2y ago
    I’m just surprised they hold up to non-EV vehicles at a similar angle/speed. At 45 degrees, seems like most ICE cars would fly through them too, except for some of the more compact ones. But especially SUVs and trucks.
- Ekaros 2y ago
  To me it seem reasonable middle ground. You get either 0 degree or 90 degree. That is glancing or head-on. 45 being between is not unreasonable option to set as coming at some repeatable angle. As you cannot test all collisions. Head on crashes have already other methodology. Which covers some ground. After all you can only do limited amount of testing.
breakyerself 2y ago
It showed a Tesla crashing at a high rate of speed and steep angle. Didn't show a comparable ice car. I am distracted by the TV. Did I miss it?
userbinator 2y ago
one piece of this was noticing EVs weigh 20 to 30% more than their gas-powered counterparts. ...which isn't much on the absolute scale; the difference in weight between a small sedan and a larger one, or an SUV or truck. If EVs weren't being stopped by guardrails, neither were the latter.
- ClassyJacket 2y ago
  Exactly. The weight of EVs is so overplayed, as if there was no difference already between a Corolla and a Camry. Look at those gigantic utes\trucks Americans drive. Suddenly weight is only a problem if the car is electric?
esjeon 2y ago
Upgrading all guardrails isn’t terribly difficult - it just takes long. Guardrails usually last 20-30 years, and governments will not replace them until they fail. Also, this experiment also means that BEVs can inflict bigger damages to other hard objects (e.g. buildings), and drivers would get injured more seriously during collision. So I think we should get a safer design that kills the kinetic energy on collision.
kmoser 2y ago
I'm surprised it took this long to figure it out. I would have thought every new model of car would be subjected to guardrail crash tests, starting with the earliest EVs and hybrids from several decades ago (Prius in late 1990s, Tesla in mid-2000s). Or maybe the media is just slow on the uptake?
ekianjo 2y ago
Makes no sense. pick up trucks in the US are way larger and heavier than regular EVs and they don't seem to raise an alert on that.
- Tagbert 2y ago
  They also don't get the clicks and eyeballs the way stories on EV do.
- seattle_spring 2y ago
  Ironically, it's only been the "huge truck with massive lift kit" type of people who have insisted that the weight of EVs makes them unusually dangerous killing machines versus ICE vehicles. It's plainly obvious that they don't actually care about safety, they just regurgitate anti-EV talking points because it supports their cultural needs to remain gas powered.
wg0 2y ago
And that EVs are mostly rich boy's toy or enthusiasts are buying them. Average Joe concerned with commute isn't buying them. They aren't doing good at car rentals even. Hertz comes to mind. Mr. Musk must be given credit that he created such a FOMO that whole car industry went into panic and started building assembly lines.
- Schiendelman 2y ago
  I live in Seattle, a region of four million. Right now I see more new EVs on the road than new non-EVs. I think Tesla 3/Y are a plurality of vehicles I see in the city.
- ClassyJacket 2y ago
  The number one selling car in the world is electric.
- thebruce87m 2y ago
  > Average Joe concerned with commute isn't buying them. Eh? Costs me 3p/mile compared to 12p/mile on my old diesel. Pre-heated/defrosted automatically every morning. Fully charged and ready to go, and I don’t have to waste 15 minutes a week driving to the petrol station and refuelling. Best commuter car I’ve ever had.
helsinkiandrew 2y ago
Similar study in Nebraska, was discussed 8 months ago: https://news.ycombinator.com/item?id=39215662 https://news.ycombinator.com/item?id=39215662 https://news.ycombinator.com/item?id=39641878 https://news.ycombinator.com/item?id=39641878
bryanlarsen 2y ago
Poorly designed EV's without a bespoke chassis are 20-30% heavier than gasoline cars. But better designed ones are much closer in weight, and those are the cars that sell well. For example, a Tesla 3 is within 5% of the weight of a BMW 3.
- seanmcdirmid 2y ago
  Pretty much: Tesla Model 3: 3,862 to 4,054 lbs BMW i4: 4,553 to 5,049 lbs Note that the model 3 and i4 are compacts (accord sized), the BMW 3 is a sub-compact. The i4 shares a chassis with the 4 series, which is 3,578 to 4,034 lbs You really feel the extra pounds also, but I still like my i4.
  - OptionOfT 2y ago
    I'm surprised the BMW 4 series is a compact, and a BMW 3 series is a sub-compact. A 3 series is 185.4 in long, a 4 series is 187.7 in long. Does that make it jump from sub-compact to compact? Apart from that, BMW wants to use its CLAR platform. Ever popped the hood of your BMW i4 and removed the 'engine cover'? What a load of wasted space there...
    - seanmcdirmid 2y ago
      I had a loaner 3 once when my i4 was in the shop. It was so much narrow than my i4, at least when parking in my tight garage situation it was really noticeable. Only a couple inches I think. A civic is 70.9 inch wide compared to an accord that is 73.3 inches wide. The 3 series is wider than a civic while the 4 series is narrower than an accord, for what it’s worth. The diff between a compact and sub-compact isn’t that great. Edit: it’s actually just an inch narrower. Goes to show how tight my parking situation is.
- emmelaich 2y ago
  And the hazard detection in a Tesla means it's much more unlikely to crash in the first place, at any great speed.
Animats 2y ago
Overview of guardrails - reasonably good video. [1] Motor Trend: "America's vehicles are fat, and its guardrails suck."[2] Motor Trend is critical of the U.Texas tests, because they didn't test larger gas-powered trucks. The current guardrail test weight for pickup trucks is 5000 pounds. That was increased from 4500 pounds in 2019. Current Ford F-150 trucks can be over 7,000 pounds, empty. The Rivian EV pickup is listed as 7,148 lbs. The Hummer EV is over 9000 lbs. Guardrails have ratings - TL1 through TL6. TL3 is most common. That's the 5000 pound pickup truck level. The standard test is not straight-on; it's 45 degrees. After all, these things are alongside roads, and are rarely hit straight on at high speed. The last big problem with guardrails was collisions with guardrail ends, especially at freeway offramps. There are good solutions for that in place now. Take a good look at the high-traffic Interstate offramp you see. There are various different crushable systems used, and they work reasonably well. The main problem is replacing them after use. They're a consumable. Low center of gravity is a big problem. Guardrail heights have been increased over the last few decades as cars got bigger. Low-CG electrics push their way under. Notice, though, that the Tesla test resulted in the vehicle traveling parallel to the guardrail after the vehicle went under it. Enough energy was absorbed to redirect the vehicle. The Rivian went clear through. Maybe for pickups above some weight drivers should have to have a commercial driver's license, the one you need to drive a real truck. [1] https://www.youtube.com/watch?v=w6CKltZfToY https://www.youtube.com/watch?v=w6CKltZfToY [2] https://www.motortrend.com/news/guardrail-safety-study-evs-popular-trucks-suvs/ https://www.motortrend.com/news/guardrail-safety-study-evs-p...
- avidiax 2y ago
  > Maybe for pickups above some weight drivers should have to have a commercial driver's license, the one you need to drive a real truck. I would love that. At the very least, anyone with an at-fault accident should be barred from driving the heaviest vehicles.
- jaidan 2y ago
  > Maybe for pickups above some weight drivers should have to have a commercial driver's license, the one you need to drive a real truck. Like the rest of the world? Australia car license limit: 4500kg for C (Car) class [0] New Zealand Car license limit: 6000kg for Class 1 (Car) [1] United Kingdom car license limit: 3500kg or 8250kg for class B [2] France limit: 4250kg towing for class B [3] Cavet: the above weights can be a vehicle or a combination vehicle weight depending on a bunch or intricate rules. [0] https://www.transport.wa.gov.au/licensing/vehicle-classes.asp https://www.transport.wa.gov.au/licensing/vehicle-classes.as... [1] https://www.nzta.govt.nz/driver-licences/getting-a-licence/licences-by-vehicle-type/what-you-can-drive/ https://www.nzta.govt.nz/driver-licences/getting-a-licence/l... [2] https://www.gov.uk/driving-licence-categories https://www.gov.uk/driving-licence-categories [3] https://www.service-public.fr/particuliers/vosdroits/F2845?lang=en https://www.service-public.fr/particuliers/vosdroits/F2845?l...
diebeforei485 2y ago
What they don't say is: (1) Vehicles are heavier now, not just EV's. (2) Regardless of the barriers you are safer in an EV because EV's don't rollover.

33 points by Gabriel54 2y ago

MBCook 2y ago

Maybe we should just have reasonable weight and size limits?

bobim 2y ago
And power limits. And bumper height compatibility. And guardrails that respect motorcyclists body integrity.
rapjr9 2y ago
So smaller EV batteries and less range and lower price. That seems ok to me. It's possible that advances in batteries will reduce battery weight, so replacing all the guardrails right away may not make sense. Difficult to predict battery future though. Maybe EV's need a cage at the front so the front end doesn't collapse so easily without an engine there?

yieldcrv 2y ago

Skip to 1:05 if you value your time to see the first video examples

analog31 2y ago
Guardrail Damage Ahead

01HNNWZ0MV43FF 2y ago

Another reason to buy a Prius > It’s not only the weight of the vehicle, TTI said. The battery used to power EVs creates a lower center of gravity and the front is a storage space instead of an engine compartment.

tw04 2y ago
Huh? It sounds like it's a reason to re-design the guard rails. EVs aren't going away short of the discovery of some miracle fuel that doesn't generate greenhouse gasses. Even with a 100% hybrid fleet, the emissions will still continue to exacerbate climate change. We either figure out how to stop burning oil, or mother nature will take care of the problem (us) herself.
- userbinator 2y ago
  Where do you think the electricity to power EVs comes from?
  - dzink 2y ago
    Nuclear and Solar, at least for ours.
  - dangrossman 2y ago
    Residential rooftop solar in the US already produces enough energy to cover the charging of every EV currently on the road, and we're adding capacity each year faster than new EVs are consuming it, so that'll continue to be true.
  - Retric 2y ago
    Where do you think gasoline comes from? Even if you collected 100% of tailpipe emissions EV’s would still be cleaner in the US.
  - Schiendelman 2y ago
    Mine's almost entirely hydro.
  - Jtsummers 2y ago
    Here (central CO) our energy supply is 33% renewable (increasing each year), 35% coal (phasing out, target 2030, NM coal plants we drew from already phased out back in 2020), 18% natural gas/oil, and 14% produced by others (no direct control). The benefit of shifting the energy from gas cars to electric is that as the grid converts to increasingly focus on renewables the overall emissions drop. Many people here are also putting in rooftop solar (this is a very sunny area, even through the winter though obviously with shorter days).

wenc 2y ago

Just curious, is this an EV thing or just a high weight and low center of gravity thing? Because a number of gas cars also fall into the latter category.

lxe 2y ago
> The battery used to power EVs creates a lower center of gravity and the front is a storage space instead of an engine compartment. These factors can all be seen in a crash test conducted at the RELLIS Campus
- aitchnyu 2y ago
  I cant brain the physics of both design details. Could you explain?
nabilhat 2y ago
In this case it's a bad test thing. The car impacted at a barrier splice which was not correctly joined. Barrier splices can come apart in the real world, but the fasteners will tear apart the sheet metal in the process. That splice gently deflected apart, like two sections of barrier were gently leaned against each other. Two posts fall over on the initial impact, one on each side of the loose splice, without causing noticable specific damage to the car. The third post absolutely caved in the front end of the car before being violently bent down underneath, as properly anchored posts do in the real world. This also isn't how this type of barrier is tested. "Barrier deflections listed below are results from crash tests with a 2,000 kg (4,400 lb) pickup truck traveling 100 km/h (62 mph), colliding with the rail at a 25-degree angle." More diverse testing done with seriousness would be a useful way to challenge if that standard continues to be appropriate, but this isn't it. https://en.wikipedia.org/wiki/Traffic_barrier#Stiffness https://en.wikipedia.org/wiki/Traffic_barrier#Stiffness

erikaww 2y ago

Couldn’t this be engineered away? Put half the battery on top and another on the bottom

breakyerself 2y ago
Or make guardrails better. The EV center of gravity is a plus in lots of other situations.

jader201 2y ago

The test seems to be sending the EV into the guardrail at a 45 degree angle, moving straight ahead. Is this common for guardrail collisions? Granted, it’s ideal if they can withstand that angle of impact, but I’m trying to understand the real world impact to safety this has.

esjeon 2y ago
Fairly common. A lot of things can happen during accidents, and cars sometimes run into guardrails at angles greater than 45 deg.
- jader201 2y ago
  I’m just surprised they hold up to non-EV vehicles at a similar angle/speed. At 45 degrees, seems like most ICE cars would fly through them too, except for some of the more compact ones. But especially SUVs and trucks.
Ekaros 2y ago
To me it seem reasonable middle ground. You get either 0 degree or 90 degree. That is glancing or head-on. 45 being between is not unreasonable option to set as coming at some repeatable angle. As you cannot test all collisions. Head on crashes have already other methodology. Which covers some ground. After all you can only do limited amount of testing.

breakyerself 2y ago

It showed a Tesla crashing at a high rate of speed and steep angle. Didn't show a comparable ice car. I am distracted by the TV. Did I miss it?

userbinator 2y ago

one piece of this was noticing EVs weigh 20 to 30% more than their gas-powered counterparts. ...which isn't much on the absolute scale; the difference in weight between a small sedan and a larger one, or an SUV or truck. If EVs weren't being stopped by guardrails, neither were the latter.

ClassyJacket 2y ago
Exactly. The weight of EVs is so overplayed, as if there was no difference already between a Corolla and a Camry. Look at those gigantic utes\trucks Americans drive. Suddenly weight is only a problem if the car is electric?

esjeon 2y ago

Upgrading all guardrails isn’t terribly difficult - it just takes long. Guardrails usually last 20-30 years, and governments will not replace them until they fail. Also, this experiment also means that BEVs can inflict bigger damages to other hard objects (e.g. buildings), and drivers would get injured more seriously during collision. So I think we should get a safer design that kills the kinetic energy on collision.

kmoser 2y ago

I'm surprised it took this long to figure it out. I would have thought every new model of car would be subjected to guardrail crash tests, starting with the earliest EVs and hybrids from several decades ago (Prius in late 1990s, Tesla in mid-2000s). Or maybe the media is just slow on the uptake?

ekianjo 2y ago

Makes no sense. pick up trucks in the US are way larger and heavier than regular EVs and they don't seem to raise an alert on that.

Tagbert 2y ago
They also don't get the clicks and eyeballs the way stories on EV do.
seattle_spring 2y ago
Ironically, it's only been the "huge truck with massive lift kit" type of people who have insisted that the weight of EVs makes them unusually dangerous killing machines versus ICE vehicles. It's plainly obvious that they don't actually care about safety, they just regurgitate anti-EV talking points because it supports their cultural needs to remain gas powered.

wg0 2y ago

And that EVs are mostly rich boy's toy or enthusiasts are buying them. Average Joe concerned with commute isn't buying them. They aren't doing good at car rentals even. Hertz comes to mind. Mr. Musk must be given credit that he created such a FOMO that whole car industry went into panic and started building assembly lines.

Schiendelman 2y ago
I live in Seattle, a region of four million. Right now I see more new EVs on the road than new non-EVs. I think Tesla 3/Y are a plurality of vehicles I see in the city.
ClassyJacket 2y ago
The number one selling car in the world is electric.
thebruce87m 2y ago
> Average Joe concerned with commute isn't buying them. Eh? Costs me 3p/mile compared to 12p/mile on my old diesel. Pre-heated/defrosted automatically every morning. Fully charged and ready to go, and I don’t have to waste 15 minutes a week driving to the petrol station and refuelling. Best commuter car I’ve ever had.

helsinkiandrew 2y ago

Similar study in Nebraska, was discussed 8 months ago: https://news.ycombinator.com/item?id=39215662 https://news.ycombinator.com/item?id=39215662 https://news.ycombinator.com/item?id=39641878 https://news.ycombinator.com/item?id=39641878

bryanlarsen 2y ago

Poorly designed EV's without a bespoke chassis are 20-30% heavier than gasoline cars. But better designed ones are much closer in weight, and those are the cars that sell well. For example, a Tesla 3 is within 5% of the weight of a BMW 3.

seanmcdirmid 2y ago
Pretty much: Tesla Model 3: 3,862 to 4,054 lbs BMW i4: 4,553 to 5,049 lbs Note that the model 3 and i4 are compacts (accord sized), the BMW 3 is a sub-compact. The i4 shares a chassis with the 4 series, which is 3,578 to 4,034 lbs You really feel the extra pounds also, but I still like my i4.
- OptionOfT 2y ago
  I'm surprised the BMW 4 series is a compact, and a BMW 3 series is a sub-compact. A 3 series is 185.4 in long, a 4 series is 187.7 in long. Does that make it jump from sub-compact to compact? Apart from that, BMW wants to use its CLAR platform. Ever popped the hood of your BMW i4 and removed the 'engine cover'? What a load of wasted space there...
  - seanmcdirmid 2y ago
    I had a loaner 3 once when my i4 was in the shop. It was so much narrow than my i4, at least when parking in my tight garage situation it was really noticeable. Only a couple inches I think. A civic is 70.9 inch wide compared to an accord that is 73.3 inches wide. The 3 series is wider than a civic while the 4 series is narrower than an accord, for what it’s worth. The diff between a compact and sub-compact isn’t that great. Edit: it’s actually just an inch narrower. Goes to show how tight my parking situation is.
emmelaich 2y ago
And the hazard detection in a Tesla means it's much more unlikely to crash in the first place, at any great speed.

Animats 2y ago

Overview of guardrails - reasonably good video. [1] Motor Trend: "America's vehicles are fat, and its guardrails suck."[2] Motor Trend is critical of the U.Texas tests, because they didn't test larger gas-powered trucks. The current guardrail test weight for pickup trucks is 5000 pounds. That was increased from 4500 pounds in 2019. Current Ford F-150 trucks can be over 7,000 pounds, empty. The Rivian EV pickup is listed as 7,148 lbs. The Hummer EV is over 9000 lbs. Guardrails have ratings - TL1 through TL6. TL3 is most common. That's the 5000 pound pickup truck level. The standard test is not straight-on; it's 45 degrees. After all, these things are alongside roads, and are rarely hit straight on at high speed. The last big problem with guardrails was collisions with guardrail ends, especially at freeway offramps. There are good solutions for that in place now. Take a good look at the high-traffic Interstate offramp you see. There are various different crushable systems used, and they work reasonably well. The main problem is replacing them after use. They're a consumable. Low center of gravity is a big problem. Guardrail heights have been increased over the last few decades as cars got bigger. Low-CG electrics push their way under. Notice, though, that the Tesla test resulted in the vehicle traveling parallel to the guardrail after the vehicle went under it. Enough energy was absorbed to redirect the vehicle. The Rivian went clear through. Maybe for pickups above some weight drivers should have to have a commercial driver's license, the one you need to drive a real truck. [1] https://www.youtube.com/watch?v=w6CKltZfToY https://www.youtube.com/watch?v=w6CKltZfToY [2] https://www.motortrend.com/news/guardrail-safety-study-evs-popular-trucks-suvs/ https://www.motortrend.com/news/guardrail-safety-study-evs-p...

avidiax 2y ago
> Maybe for pickups above some weight drivers should have to have a commercial driver's license, the one you need to drive a real truck. I would love that. At the very least, anyone with an at-fault accident should be barred from driving the heaviest vehicles.
jaidan 2y ago
> Maybe for pickups above some weight drivers should have to have a commercial driver's license, the one you need to drive a real truck. Like the rest of the world? Australia car license limit: 4500kg for C (Car) class [0] New Zealand Car license limit: 6000kg for Class 1 (Car) [1] United Kingdom car license limit: 3500kg or 8250kg for class B [2] France limit: 4250kg towing for class B [3] Cavet: the above weights can be a vehicle or a combination vehicle weight depending on a bunch or intricate rules. [0] https://www.transport.wa.gov.au/licensing/vehicle-classes.asp https://www.transport.wa.gov.au/licensing/vehicle-classes.as... [1] https://www.nzta.govt.nz/driver-licences/getting-a-licence/licences-by-vehicle-type/what-you-can-drive/ https://www.nzta.govt.nz/driver-licences/getting-a-licence/l... [2] https://www.gov.uk/driving-licence-categories https://www.gov.uk/driving-licence-categories [3] https://www.service-public.fr/particuliers/vosdroits/F2845?lang=en https://www.service-public.fr/particuliers/vosdroits/F2845?l...

diebeforei485 2y ago

What they don't say is: (1) Vehicles are heavier now, not just EV's. (2) Regardless of the barriers you are safer in an EV because EV's don't rollover.