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Tell HN: I think I found Toyota's battery

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Re: Tell HN: I think I found Toyota's battery

#141

Post by solardev »

peterdsharpe wrote: post #116
hadlock wrote: post #100

Earlier quoted context omitted.

Someone else pointed out LD50 is ~700ppm It's unlikely you'd be exposed to this level for any period of time unless the battery ruptured into the car, underwater, with the windows up, in which case you have bigger problems. You're unlikely to to see 700ppm in an outdoor situation like a car wreck or battery malfunction on the highway during a rainstorm. Atmospheric CO2 is about 450ppm for comparison. Ammonia is a sup…

I think H2S is somewhat bigger of a safety risk than presented here. For example, check out this case where what you describe (battery rupture) happened, killing both occupants from H2S inhalation: https://web.archive.org/web/20161005164308/http://www.wesh.c... And this was only from a starter battery, not a battery sized for vehicle locomotion.

It's interesting that Porsche put the battery under the driver's seat (in the cabin? unclear). Wonder if that made it more dangerous. Are modern EV batteries also in the passenger area or in their own little armored section...?

Re: Tell HN: I think I found Toyota's battery

#142

Post by hyperthesis »

skrebbel wrote: post #94
DiabloD3 wrote: post #89

Hey scythe, write a blog abut this. This seems like semi-decent conjecture that'd get a lot of pull with the electric car crowd on the Fediverse, and you'd get a fair number of eyeballs pointed in the same direction.

A Tell HN is basically a blog post right? Permalink, comments, it’s got it all. There’s even an RSS feed.

It's greyed out and hard to read.

Re: Tell HN: I think I found Toyota's battery

#143

Post by machdiamonds »

hyperthesis wrote: post #142
skrebbel wrote: post #94

Earlier quoted context omitted.

A Tell HN is basically a blog post right? Permalink, comments, it’s got it all. There’s even an RSS feed.

It's greyed out and hard to read.

If you use Firefox, Reader View is pretty nice.

Re: Tell HN: I think I found Toyota's battery

#144

Post by npunt »

solardev wrote: post #141
peterdsharpe wrote: post #116

Earlier quoted context omitted.

I think H2S is somewhat bigger of a safety risk than presented here. For example, check out this case where what you describe (battery rupture) happened, killing both occupants from H2S inhalation: https://web.archive.org/web/20161005164308/http://www.wesh.c... And this was only from a starter battery, not a battery sized for vehicle locomotion.

It's interesting that Porsche put the battery under the driver's seat (in the cabin? unclear). Wonder if that made it more dangerous. Are modern EV batteries also in the passenger area or in their own little armored section...?

It was probably put there for weight distribution as Porsche would be more likely to optimize for that despite the user inconvenience it may cause

Re: Tell HN: I think I found Toyota's battery

#145

Post by Nition »

hamandcheese wrote: post #35
ultrarunner wrote: post #18

Earlier quoted context omitted.

If it could only reduce the weight of current EVs that would be a win. Most electric vehicles weight 1000 lbs or more than their ICE counterparts, and in the extreme case of the Hummer, the total weight is over 9000 lbs. Vehicles seem to be continuously ballooning in size, so whether that continues or eventual legislation forces more reasonable sizes, higher energy density would be very welcome.

When will this meme die? A Model 3 is very comparable in weight to an Audi S3. The Hyundai Ionic 5 is comparable weight and interior volume to a Toyota Rav 4. The Hummer is a monster either way and is not a good sample.

Everyone here so far is comparing different models, but you can just compare the exact same car to remove (most) other factors.

2020 Kia Niro LX (1.6L petrol engine): 3,100lb

2020 Kia Niro Touring (1.6L petrol engine): ~3,250lb

2020 Kia Niro EX (64kWh EV): 3,854 lbs

Batteries are heavy.

Re: Tell HN: I think I found Toyota's battery

#146

Post by npunt »

hadlock wrote: post #100
alex7734 wrote: post #24

> it could release highly toxic hydrogen sulfide gas. How bad is it in real world conditions? Because from what I'm reading it's not the "it makes you sick" kind of toxic, but rather the "it kills you in seconds" kind of toxic.

Someone else pointed out LD50 is ~700ppm It's unlikely you'd be exposed to this level for any period of time unless the battery ruptured into the car, underwater, with the windows up, in which case you have bigger problems. You're unlikely to to see 700ppm in an outdoor situation like a car wreck or battery malfunction on the highway during a rainstorm. Atmospheric CO2 is about 450ppm for comparison. Ammonia is a sup…

Cars are often in tunnels, could be dangerous there?

For comparison purposes, note that indoors CO2 will go from 400 -> 1000ppm+ rather quickly if its not ventilated

According to this source [1], CO2 went from 400 -> 3000ppm inside a car cabin in 30mins, which is ~86ppm/min just from breathing. I could easily imagine a gas inside a car leaking at a faster rate and reaching 700ppm in a very short period of time.

[1]: https://www.co2meter.com/blogs/news/high-carbon-dioxide-co2-...

Re: Tell HN: I think I found Toyota's battery

#147

Post by lelandbatey »

barrkel wrote: post #113
lelandbatey wrote: post #19

Earlier quoted context omitted.

Since it's a bit more than a doubling of energy density, it's less that you can get a 500+ mile car and more that you can drop the price & weight of a 300-400 mile car. Imagine cutting the weight of an EV battery by 500 pounds while maintaining its current capacity. All that weight savings will probably get you some additional range, and save you on cost of materials, meaning you could cut the battery down a bit more…

I doubt range is increased much by reduced weight. Only rolling resistance is reduced, but most resistance at speed is from air resistance. Since energy is reclaimed from braking, the extra mass for acceleration is balanced by the extra mass for stopping, so it doesn’t help much with stop start traffic. That’s how I mentally model it anyhow.

It's true that it's not a huge savings, but there's some savings. The EPA estimates approximately 1% reduction in fuel economy for each 100lbs added, so you might get a few % from the the battery weight savings.

Re: Tell HN: I think I found Toyota's battery

#148

Post by hamandcheese »

lastofthemojito wrote: post #47
hamandcheese wrote: post #35

Earlier quoted context omitted.

When will this meme die? A Model 3 is very comparable in weight to an Audi S3. The Hyundai Ionic 5 is comparable weight and interior volume to a Toyota Rav 4. The Hummer is a monster either way and is not a good sample.

I feel like that's quite a stretch of the word comparable. The Model 3 is 14% heavier than the Audi: https://www.edmunds.com/car-comparisons/?veh1=401999985&veh2... And the Ioniq5 is 35% heavier than the RAV4: https://www.edmunds.com/car-comparisons/?veh1=401958795&veh2...

You are comparing the heaviest Ioniq to a lighter trim of Rav 4. If you compare models more similar in price the difference is significantly less.

Re: Tell HN: I think I found Toyota's battery

#149

Post by sheepshear »

oblio wrote: post #134
sheepshear wrote: post #125

Earlier quoted context omitted.

The premise is that the enclosure is already somehow breeched. Squeezing a battery is bad and it makes bad situations worse.

The thing is, batteries can weight half a ton. At triple the energy density they could almost armor plate it to tank levels. I imagine most of us aren't under Javelin attack during road trips :-p

Funny but there's still corrosion, cracking, and holes to connect wires to the battery.

Re: Tell HN: I think I found Toyota's battery

#150

Post by tadfisher »

hinkley wrote: post #74
Detrytus wrote: post #51

Earlier quoted context omitted.

Actually, when demand for EVs goes up, lithium mining won't be able to keep up, so in the next decade or so we'll see steep increase in battery prices.

In the next decade you will see more reliance on technology that becomes cheaper than simply throwing lithium at the problem. It's the same thing with many techs. In the 70's we thought we would run out of oil by 2000, and a lot of asshats in the 80's and 90's crowed about how stupid those so-called experts were. What happened in the 80's and 90's was ground sensing radar found more oil, horizontal drilling found way…

That's not what Peak Oil means, but I think you know this. The cost of oil will never return to pre-2000s levels because meeting demand necessitates more expensive extraction technologies like shale and offshore. In that sense (the correct one), the prediction of peak oil by 2000 was remarkably accurate.
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