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Tesla Model S achieves best safety rating of any car ever tested

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Re: Tesla Model S achieves best safety rating of any car ever tested

#181

Post by tmzt »

lutusp wrote: post #155
abalone wrote: post #151

Earlier quoted context omitted.

Wish I had your crystal ball. With improvement, I was referring to the complexity of cutting someone out of a Tesla and all the no-cut zones that could electrocute passengers, emergency responders, even guys towing wrecks. You're right, there is no real safety record yet.

> With improvement, I was referring to the complexity of cutting someone out of a Tesla and all the no-cut zones that could electrocute passengers, emergency responders, even guys towing wrecks. As an electrical engineer with spacecraft experience, I can say that a car like the Model S isn't likely to electrocute anyone. While extracting someone from a wreck, emergency workers use tools like the "jaws of life", stron…

Would an independent accelorometer in the battery assembly shut of the power when the car is involved in a collision?

It wouldn't make sense for it to be dependent on a link from the airbag sensors, it would have to be local to the power plant.

Re: Tesla Model S achieves best safety rating of any car ever tested

#182

Post by knowaveragejoe »

vidarh wrote: post #16
knowaveragejoe wrote: post #4

> The Model S lithium-ion battery did not catch fire at any time before, during or after the NHTSA testing. It is worth mentioning that no production Tesla lithium-ion battery has ever caught fire in the Model S or Roadster, despite several high speed impacts. While this is statistically unlikely to remain the case long term, Tesla is unaware of any Model S or Roadster occupant fatalities in any car ever. I can't hel…

It might be, but also consider that lithium-ion batteries do have a reputation, and catching fire or exploding would be high on the list of things that anyone wanting to sow doubt about the safety of an electric car might bring up, so pre-empting it might be worthwhile for that reason too.

I think it's both, as what you mention is quite true and Musk has made some comments about "getting it right" after the Dreamliner battery issue.

Re: Tesla Model S achieves best safety rating of any car ever tested

#183

Post by Casseres »

masklinn wrote: post #144
abalone wrote: post #142

Earlier quoted context omitted.

That's a very big question and probably only time will tell. Without getting into it too much, a very basic difference is.. Gas can explode like a bomb but (a) it needs an ignition source and (b) there can be visible signs when the fuel is leaking to let you know to take extra precautions (like spray fire retardant). You can actually get fuel on you and you'll be fine. High voltage systems don't (usually) explode, bu…

> Gas can explode like a bomb but (a) it needs an ignition source and (b) there can be visible signs when the fuel is leaking to let you know to take extra precautions (like spray fire retardant). And (c) if it's a diesel car (very common in europe), good luck getting it to explode.

Want to scare your friends? Put out a lit match or cigarette using Diesel fuel.

Diesel fuel requires a lot of heat to combust. Diesel engines don't contain spark plugs, they heat the fuel by compressing the air that the fuel is atomized in.

Re: Tesla Model S achieves best safety rating of any car ever tested

#184

Post by bryanlarsen »

kirse wrote: post #86

I'm sorry, but as a car enthusiast who spent much of his younger years devouring every ounce of Road&Track/Car&Driver mags, the phrase "any car ever tested" is a bit over the top... I'm almost positive the McLaren F1 (a car 20 years older) fared better than the Tesla in safety testing and was capable of being driven away after the testing finished... F1 @ 30mph: http://img.photobucket.com/albums/v482/Peloton25/McLare…

That's a single test. It's not surprising that there's a car out there that can do better than a Tesla in one of the IIHS tests. However, to get a 5 star rating, you have to get a "good" on all of the tests, which I am very confident the F1 does not do.

Being a rear-engine design gives both the Tesla & the F1 a huge advantage in frontal tests. But I'm willing to bet that a side impact test or a roll over test will show much different results...

Re: Tesla Model S achieves best safety rating of any car ever tested

#185

Post by tocomment »

tlb wrote: post #40
tocomment wrote: post #38

I've always found the star safety ratings confusing especially when I've noticed compact cars getting the same stars as large cars. I'd like to just see each model ranked by number of fatalities per mile driven. Wouldn't that make a lot more sense? Is such a statistic available anywhere?

They exist [1] but can be misleading because different kinds of people buy different kinds of vehicles. So muscle cars and 4x4s have higher crash rates than minivans and economy sedans mainly because of the people that drive them. [1] http://www.iihs.org/externaldata/srdata/docs/sr4204.pdf

Thanks! I guess you could still use it to compare between say minivans?

Re: Tesla Model S achieves best safety rating of any car ever tested

#186

Post by cheapsteak »

RomP wrote: post #22

This is simply unkind to the competition (and to the poles alike): "Tesla achieved this outcome by nesting multiple deep aluminum extrusions in the side rail of the car that absorb the impact energy (a similar approach was used by the Apollo Lunar Lander) and transfer load to the rest of the vehicle. This causes the pole to be either sheared off or to stop the car before the pole hits an occupant." There's winning an…

Similarly: "during validation of Model S roof crush protection at an independent commercial facility, the testing machine failed at just above 4 g's."

Re: Tesla Model S achieves best safety rating of any car ever tested

#187

Post by IgorPartola »

axylone wrote: post #84
RomP wrote: post #22

This is simply unkind to the competition (and to the poles alike): "Tesla achieved this outcome by nesting multiple deep aluminum extrusions in the side rail of the car that absorb the impact energy (a similar approach was used by the Apollo Lunar Lander) and transfer load to the rest of the vehicle. This causes the pole to be either sheared off or to stop the car before the pole hits an occupant." There's winning an…

Here's the video of the Tesla pole test: http://youtu.be/_Al3IUHt9Wc?t=32s Honda Accord for comparison: http://youtu.be/ycntFFUfGkU?t=30s

Anyone else notice Tesla's flying rear view mirror that nearly hit the dummy in the face? Maybe they forgot to apply the little alcohol wipe before gluing it on the windshield :).

Re: Tesla Model S achieves best safety rating of any car ever tested

#188

Post by triplepoint217 »

abalone wrote: post #110

This is all very good PR.... BUT. The critical safety concern with the Tesla is....... You guessed it. The high voltage system. It can kill you or a first responder with a touch. It's not just about batteries catching fire, although that's gotten a lot of press lately. A chief concern during a Tesla accident is the exposure of high voltage components. It's a big concern for first responders. Read it from the horse's…

Does anyone know what the actual voltages are?

Just because it is high relative to the usual 12V of cars does not mean it is terrifically fatal.

An anecdote to give you a picture of things: Electric arc welders operate at around 60V with a very large amount of current. However the electricity is not particularly the dangerous thing about them, it is the 9000F arc you are making and the molten steel. So to demonstrate that we shouldn't freak out about the electric danger and worry more about the heat, my instructor had someone touch the business end with one hand and the ground electrode with the other. Bit of a tingle but certainly didn't stop their heart or anything. Welders are kept at low voltage for this reason.

I assume that it must be somewhat dangerous because of the responder guides warning, but I would want to know the actual voltage before drawing conclusions. If the voltage is 112 or less (or even 220 or less), it should be possible to be pretty safe with some fairly manageable precautions.

Re: Tesla Model S achieves best safety rating of any car ever tested

#189

Post by sergiosgc »

abalone wrote: post #169
lutusp wrote: post #155

Earlier quoted context omitted.

> With improvement, I was referring to the complexity of cutting someone out of a Tesla and all the no-cut zones that could electrocute passengers, emergency responders, even guys towing wrecks. As an electrical engineer with spacecraft experience, I can say that a car like the Model S isn't likely to electrocute anyone. While extracting someone from a wreck, emergency workers use tools like the "jaws of life", stron…

Hi there. Go ahead and watch this video from Tesla about how to cut someone out of a Tesla. The very first step is to cut the circuit like you say, but there are a few things you overlooked. Much of the video is concerned with instructing responders how to cut around components that may remain electrified such as the converter and capacitors which, in Tesla's own words, present a "serious hazard of shock" because "th…

Nitpicking, I know, but releasing 400 volts means nothing. Current kills, tension does not. It all hinges on the internal resistance of the power source.

Re: Tesla Model S achieves best safety rating of any car ever tested

#190

Post by gambiting »

agumonkey wrote: post #128
abalone wrote: post #110

This is all very good PR.... BUT. The critical safety concern with the Tesla is....... You guessed it. The high voltage system. It can kill you or a first responder with a touch. It's not just about batteries catching fire, although that's gotten a lot of press lately. A chief concern during a Tesla accident is the exposure of high voltage components. It's a big concern for first responders. Read it from the horse's…

About that, do cars attempt to shut down engines, fuel intake and electric pathways when detecting a collision ? I remember Liquid Gas vehicles having an emergency outlet to avoid fire/explosions. In Tesla's case that would be cutting the battery off the circuit and maybe putting it into a 'fast drain' mode ..

Most cars automatically shut down fuel supply to the engine when a collision is detected. Even if it's just a minor hit the engine can't be started again without clearing the collision warning from the computer.
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