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Comment by IgorPartola | Hacker News Reader

12 crashes is not a huge sample size. Also, potholes and other road hazards are so common that if 0.1% of encounters with them causes a fire that ruins the very expensive battery pack, it is an issue. Overall, yes, superior engineering prevented the problem from being worse than it was. However, there is still a problem.

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The sample isn't 12 crashes. It is the 12 cars that crashed plus all the other cars that didn't.

That's... not true. The question is "how likely is there to be an electrical fire in the Tesla, given that it has crashed (or is crashing)" not "how likely is there to be an electrical fire".

It's easy enough for things not to catch flame when they're being used properly; the real test is how things behave when other things are going wrong.

That's not to say that this means all Tesla cars are fiery death-traps of doom. Just that the sample size really is the number of crashed cars.

Following your logic, we can ignore Tesla cars that catch fire without crashing, because we can assume they're not going to catch flame when they're used properly; We can assume cars that don't crash aren't going to catch fire anyway, so, even if they may happen, let's throw that data away, because we know our assumption holds true.

That's ridiculous.

That is besides the point. We are talking about what happens when your Tesla S does crash. There is on "if" in the certainty that Teslas will be involved in accidents. The questions are "will they catch fire when they crash?" and also "how bad will that fire be for persons and property involved?"

There's also "Under what conditions when Tesla cars crash will they catch fire", and then you only look at your 12 crashes, and that's when everything goes wrong.

    The Space Shuttle Challenger exploded shortly after take-off in January 
    1986. Subsequent investigation determined that the cause was failure of 
    the O-ring seals used to isolate the fuel supply from burning gases.....

    NASA staff had analysed the data on the relation between ambient 
    temperature and number of O-ring failures (out of 6), but they had 
    excluded observations where no O-rings failed, believing that they were 
    uninformative. Unfortunately, those observations had occurred when the 
    launch temperature was relatively warm (65-80 degF).

http://www.datavis.ca/gallery/missed.php

Let's look at this question "how bad will that fire be for persons and property involved?"

You look at your 12 crashes where fire occurs, so (e.g.) 6 crashes. Of 6 crashes 3 were accompanied with injuries. All 3 crashes that were accompanied by electrical fires and injuries occurred was when the car's speed was between (e.g.) 40mph and 50mph. Does that mean when the speed is not between 40mph and 50mph, people won't be injured when there's a crash and a fire? It means nothing like that but it's too easy to make a wrong conclusion; you're skipping all the other data where injuries and/or fires happen independently of crashes.

Sure, you can look at all the crashes, but you'll still run into exactly the same problems with insufficient sample size because now you're dealing with a rare event, which means the required sample size balloons massively.

IMHO, there is a major problem with Tesla's batteries. Boeing has had issues with its lithium-ion batteries catching on fire. I wouldn't be surprised if more Teslas have the same issues in the future.

> IMHO, there is a major problem with Tesla's batteries.

Is this based on any kind of information, or just supposition stemming from the problems Boeing had (where, IIRC, Tesla offered to provide engineering assistance).

Well, the Chevy Volts' lithium ion batteries also have fire issues too. Not to mention overheated laptops with li-ion batteries that have caught on fire.

We're still waiting on any categorical information from you, other than your baseless fears stemming from problems with wholly different companies using similar technology.

News, Every car has batteries that are potential fire/explosion/acid explosions.

I've seen a standard 12v lead acid battery evaporating/boiling hydrochloric acid out of its vent holes, I've also seen one smoking about to explode.

OK, add every laptop manufacturer, cellphone manufacturer, and any variety of portable device manufacturer on the planet to that list, then, as lithium ion or polymer batteries are flammable no matter what.

I assume you have a suggestion as to how this could be remedied? Or, actually, looking at your comment history, I see you are also a climate change denialist.

So, which oil giant do you work for, for whom you are spreading FUD?

Yes, please accuse anyone who disagrees with you as being a paid shill. Saying that the IPCC has lowered estimates, which it has admitted in its report, is now climate change skepticism? Really?

http://www.mercurynews.com/business/ci_24229744/tesla-says-c...

"But lithium-ion batteries have raised concerns in other vehicles. Two years ago, battery fires broke out in three Chevrolet Volt plug-in hybrid cars after crash-testing."

"Two years ago, battery fires broke out in three Chevrolet Volt plug-in hybrid cars after crash-testing."

"After" being the operative word. They crashed the Volts for testing purposes and then left them sitting outside with a nearly full but damaged battery. THREE WEEKS LATER a fire started.

When testing gasoline powered cars it is standard procedure to empty the tank immediately after crashing it, if they had drained or removed the Volts' batteries in a similar fashion nothing would have happened.

https://publichd.se/index.php?page=torrents&search=&active=0...

> ""After" being the operative word. They crashed the Volts for testing purposes and then left them sitting outside with a nearly full but damaged battery. THREE WEEKS LATER a fire started."

Well damn, those sound like verified deathtraps!

Seriously, the fact that she had to reach back two years probably says enough. On the general note of battery safety in crashes, there have been several Tesla Roadster crashes (to be expected with that style of car) (http://www.wreckedexotics.com/tesla/), how many of them resulted in dangerous battery fires? Clearly these batteries do not present a serious safety concern.

I hate the "you are a shill" retorts too, but damn if your response doesn't make it look like they are correct in this case.

> "But lithium-ion batteries have raised concerns in other vehicles. Two years ago, battery fires broke out in three Chevrolet Volt plug-in hybrid cars after crash-testing."

Imagine that, structurally compromised systems not disposed of properly are dangerous. That says more about GM than it does the technology.

When I have batteries take damage (falls, shorts, the ever popular screwdriver through them) they are disposed of properly immediately. I also only use proper chargers and don't over charge my batteries. Guess what? I've never had a fire caused by the battery (I've had people plug in components in reverse and blow up the diodes a couple times). I've been working with various battery technologies on a near daily basis for the last 14 years without incident.

Disclaimers: I'm a robotics/electric vehicle enthusiast. I don't do this stuff as my day job any more. I formerly worked in a university research lab building H2 powered race cars.

So, which oil giant do you work for, for whom you are spreading FUD?

First of all, I absolutely agree with what you have to say about the danger of batteries as an energy storage source. Spot on. Good work.

But please, please, please, let's not throw around "paid shill" accusations here. Even if it may be true, it degrades the discourse of conversation for the entire community. Your comment's point was perfectly valid without that.

Sally888 is a transparent concern troll. It's disappointing to see HN fall for it so easily.

I agree that we shouldn't be throwing around "paid shill" accusations. Downvoting is better.

Your humble opinions appear to be (a) anti L-Ion battery and (b) climate change skepticism. Is this a fair summary?

What a blatant ad hominem and straw man attack. Do you like to misrepresent someone's positions because they have differing opinions from yours?

So these are not your opinions?

You said "IMHO ..." and then asserted something with no evidence. So the only germane information is the quality of your opinions. I made no assessment of those opinions, I simply listed what I found, based on your posts, and asked for confirmation. If merely listing these things constitutes an ad hominem attack, then it says more about your opinions than it does about me.

Let's be fair here.

"You said "IMHO ..." and then asserted something with no evidence."

Why would you expect something else when someone starts their post with IMHO?

> If merely listing these things constitutes an ad hominem attack, then it says more about your opinions than it does about me.

Your post had an obvious tone to it.

Tone, obvious or otherwise, does not constitute ad hominem either.

If your answer to the question was "no", you should say "no" and then clarify. It's not that hard.

I neither like misrepresenting other people's positions nor am I prone to doing it despite not liking it.

Have I misrepresented your positions?

If your answer was "no" then why not say that?

...not sure if you've mistaken me for someone else. I have no part in this discussion except making the procedural point.

Whoops. Sorry about that.

My point (addressed incorrectly) stands. It makes less sense for me to answer "no" than for the person I was responding to to answer "no". If I was making a "straw man" then in what way was it straw? If I was misrepresenting his/her opinions, how so? Otherwise, if more-or-less accurately summarizing a person's positions is ad hominem then what does that say of those positions?

Elon Musk mentioned the battery problems that Boeing had / has, and offered to work with them to solve the problem that they had solved themselves..

Yes, but it seems that that may have the same issues themselves. Li-ion batteries are notorious for catching on fire. Yes, the sample size is too small to make a determination on Tesla but I suspect they may run into the same issues as Boeing as they sell more cars.

This is why people call you 'shill'. You aren't disagreeing, just using leading speculation. These are specifically not the same issues as Boeing, whose design Musk criticised for ability to produce 'domino effect' fires that get out of control very fast. That did not happen here.

Casting aspersions like 'li-ion are notorious' also stinks, much like the smell of gasoline before it (notoriously) explodes.

Ignoring the facts of the particular case whilst hugely generalising about the technology isn't a good foundation of debate.

What are your qualifications with regards to battery chemistry and energy management system engineering? I ask only because you said this is your opinion.

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