ggreer

> Totally different subject.

Yes, I was using an analogy.

I don't know what's going on with you today. You get hung up on language even when you know what I mean. You argue from authority, eg: "former gas station owner here" and "I use Lithium Ion batteries in volume", as if those experiences refute statistics. You don't address my stats about vehicle fire fatalities. You don't explain why you think my conclusion doesn't hold up. And you won't say what would change your mind.

We're not having a debate. You're just contradicting me.

It's true that diesel is harder to ignite than gasoline, but statistically they're not much safer than gasoline, and EVs have a lower fire risk than both. Last year, diesel vehicles accounted for 11% of vehicle miles traveled in the US and were responsible for around 12% of vehicle fire deaths. EVs were 3% of vehicle miles traveled and less than 1% of vehicle fire deaths.

Diesel vehicles usually have much larger fuel tanks than gasoline vehicles, so while the chances of a crash causing a diesel fire are lower, the consequences tend to be worse. If the stats are to be believed, the two factors balance each other out.

I'm pretty sure you're reading the paper wrong. Of the 29 tests they did, 5 were in air, and all of those were with fully charged batteries. The 5x ratio is the difference between electrical energy stored in the battery and energy released in atmosphere. They did not measure different states of charge versus energy released in atmosphere. That's why the figures for the nitrogen and atmosphere tests are bar charts instead of line charts.

The relationship between energy stored and energy released was mostly determined by how big the batteries were, not their state of charge. Only 4 of their tests varied state of charge, and those were all in vacuum (with cells #1 & #6), and state of charge was never below 60%.

Yes, I know that petroleum refers to the raw material that is used to make gasoline and diesel. I needed a term that was less cumbersome than "diesel and gasoline", and "petroleum" seemed apt. If you have a suggestion for some other term, I'm all ears.

I did correct for installed base. I'm using fatalities per vehicle mile traveled. As I said, diesel vehicles are 11% of vehicle miles traveled in the US and responsible for 12% of vehicle fire deaths in the US. EVs are 3% of vehicle miles traveled and less than 1% of vehicle fire deaths, so they're safer than diesel. The only way this could be false is if battery fire deaths are grossly underreported. That seems unlikely to me, as deaths caused by any new technology tend to be overreported. It should also be surprising that battery fire deaths are so rare, because we have little experience dealing with them. Over time, we should expect the danger of battery fires to decrease as technology and emergency training improves.

At this point, I don't know what would change your mind on this topic. I would change my mind if stats showed higher fire fatality rates per vehicle miles traveled for EVs, but that doesn't seem to be the case. I feel like I'm arguing with an anti-nuclear person. Statistics show that nuclear is extremely safe, but anti-nuclear activists ignore stats and point to nuclear accidents and the dangers of radiation. Meanwhile they ignore or discount the harms caused by alternatives. I don't see how your line of argument is any different.

If we're going to count industrial accidents, then oil kills way more people. There are deaths from disasters involving wells, refineries, pipelines, tankers, and gas stations. But because they've been happening for over a century, we accept them as a fact of life. Even correcting for the much smaller install base of EVs and lower number of vehicle miles traveled, fossil fuels are far more deadly.

By petroleum I mean gasoline and diesel.

Diesel vehicles are 11% of vehicle miles traveled in the US, and around 60 people died in diesel vehicle fires last year (12% of vehicle fire fatalities). So they seem to be as dangerous as gasoline vehicles. This is probably because while diesel is more difficult to ignite than gasoline, diesel vehicles tend to have larger fuel tanks, so the harm caused by a diesel fire tends to be greater.

The "I'm not sure" referred to road damage. The "definitely" referred to risk to people.

The fact that some people have died in lithium battery fires doesn't tell you if they're a greater risk than petroleum vehicle fires. Around 500 Americans die in vehicle fires every year. Last year, EVs were around 3% of vehicle miles traveled in the US, so if they're as dangerous as petroleum vehicles, we should expect 15 battery fire deaths in 2025. The actual number seems to be 2 or 3.

I'm not sure, but diesel fires are definitely more of a risk to people. Fuel can quickly spread and ignite before people in the vehicle (or bystanders) have a chance to escape. Lithium battery fires are more contained because individual cells spew flame, which heats up nearby cells, which then undergo thermal runaway. This means that battery fires take longer to release their energy, which is annoying for extinguishing them, but good for anyone who needs to get out of the wreck.

Lithium battery energy density is much lower than petroleum, so the difference between a fully charged 100kWh battery (which weighs over half a ton) and an empty one is less than 3 gallons of diesel. Most of the energy expended in a battery fire is from the electrolyte reacting with the cathode material.

Over/under-charged batteries are a safety hazard because they can generate hydrogen gas which can initiate a fire, but the energy released from the fire will be pretty much the same.

That user is not Greg Egan.

That's not correct. Immobilizers are not common in Japan or South Korea, both of which have extremely low auto theft rates. Canada has mandated immobilizers since 2007 and its auto theft rate is 248.5 per 100k per year, which is only slightly lower than the US, but still 17 times higher than Japan and 50 times higher than South Korea. Immobilizers have also been required in Australia since 2001, but its auto theft rate is the same as Canada.

If you measure auto theft rate per vehicle (not per person), then the US has the same rate as Canada. There are 16% more auto thefts per capita in the US, but the US also has 17% more cars per capita than Canada.

If lack of immobilizers was the main factor, Canada would have significantly lower auto theft rates than the US, and countries that mandated immobilizers would not have theft rates 15x higher than countries where they were uncommon. Neither of these are true, so immobilizers are most likely not the main factor in auto theft rates.

Auto theft rates are mostly determined by car ownership rates and the number of auto thieves on the street. The number of auto thieves on the street is determined by how quickly they are caught, and how long they are locked up for. Auto theft recidivism rates are higher than any other crime, including drug offenses. Around 80% are re-arrested within 3 years of being released. Considering the clearance rate for auto theft is around 10%, that means the average auto thief is stealing a lot of cars before being caught again, and the actual recidivism rate is higher than 80%.

I'm pretty sure Apple does use CRLs, but for some reason your phone has a problem fetching them. Yesterday my iPhone SE running iOS 15.8.8 did connect to the sites, but refused to connect about 30 minutes later.