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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

#161

Post by cryptonector »

ultrarunner wrote: post #25
alostpuppy wrote: post #17

Earlier quoted context omitted.

Out of curiosity, What is the wh/kg for petrol?

Wikipedia says 13000 Wh/kg, but you have to keep in mind that due to physics, wear considerations, and emissions regulation, most cars are only 20-40% efficient. At a 20% efficiency, that's 2600 Wh/kg. This is further constrained by gear ratios, meaning not all power is available at all times.

> This is further constrained by gear ratios, meaning not all power is available at all times.

CVTs enter the chat.

> At a 20% efficiency, that's 2600 Wh/kg.

Hybrids do better, of course.

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

#162

Post by AtlasBarfed »

canoebuilder wrote: post #6

> 750 Wh/kg is great. To put it mildly. Energy density in the current leaders in that category, lithium ion batteries, 250-270 wh/kg. So, provided a similar or better ratio of watt-hours to unit of volume, we’re basically looking at tripling the energy storage of EVs or significant weight reduction, in the ideal scenario of this design being a safe and cost effective replacement for current batteries.

It's within range of some of the sulfur techs I've seen in papers though. The sulfur techs appear safer and more abundant.

Both aren't commercialized either... For some reason, I suspect sulfur techs will go to market sooner.

What is apparent is that in 10 years battery tech will be in a much better place than it is now: 2x - 3x the density, safer, 1/2 or less the (inflation adjusted) cost. Sure that's not Moore's law rate, but that will be nonetheless revolutionary.

240 wh/kg has already been commercialized by Gotion in LMFP chemistry, so that's cobalt-free/nickel-free. 160 wh/kg sodium ion should utterly revolutionize city transportation, you don't even need lithium for that and it should be a 200-300 mile car (EPA not WLTP) or better.

IMO most car companies are probably chasing the high density LMFP and Sodium Ion for the next 5-7 years, and leaving nickel-cobalt for things that truly need it. The issue with nickel-cobalt is that the safety systems consume so much at the pack level that 200+ wh/kg LFP is basically the same density. And Gotion's 240 wh/kg will probably be functionally more dense at Cell-to-Pack densities as well as cheaper.

We still need that high density breakthough through, the US Market will probably demand 400 mile ranges (see Tesla range "fraud" story) for true mass market stupid driver adoption, especially for all those men that just have to drive a full size pickup and then buy things for it to tow.

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

#163

Post by ultrarunner »

cryptonector wrote: post #161
ultrarunner wrote: post #25

Earlier quoted context omitted.

Wikipedia says 13000 Wh/kg, but you have to keep in mind that due to physics, wear considerations, and emissions regulation, most cars are only 20-40% efficient. At a 20% efficiency, that's 2600 Wh/kg. This is further constrained by gear ratios, meaning not all power is available at all times.

> This is further constrained by gear ratios, meaning not all power is available at all times. CVTs enter the chat. > At a 20% efficiency, that's 2600 Wh/kg. Hybrids do better, of course.

CVTs enter the chat, but it's mostly to ask when they'll be replaced so you can use them again.

(I don't remember details, but we decided to specifically avoid cars with CVTs because of reliability issues. Sure enough, the only person I know with a CVT is having belt slipping issues. Seems like certain manufacturers were switching back to dual clutch arrangements)

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

#164

Post by AtlasBarfed »

gorjusborg wrote: post #117
dangus wrote: post #9

Earlier quoted context omitted.

I think for the EV skeptics it’s easy to forget how fast battery chemistry has been evolving. There’s an common assumption that the EV status quo of 300 mile range at barely-affordable prices will continue forever, and therefore with all the woes surrounding charging and bad weather affecting range, EVs are dead in the water. Ten years ago $30k got you 75 miles of range out of a Nissan Leaf. Fast forward to present d…

Are there EV skeptics? I don't think so. There are average people and EV fanboys. It's just that fanboys call the other people skeptics. EVs are in early adoption still, from my point of view. Try to pump it all you want, but EVs offer far less utility for a higher price, and they are more inconvenient. Until the industry standardizes on batteries and stations offer pre-charged battery swaps, I'll hang on to my ICE m…

EVs are quieter, smoother, higher torque, better accelerating, for simpler drivetrain, less maintenance.

I've seen so many TCO reports on Teslas being cheaper than new ICE cars, and that was before the Tesla price cuts and the insane inflation in new car costs in ICE.

As for the "new car cost", I suspect Tesla is already at cost-per-vehicle parity with an ICE, but Tesla is keeping a high margin on their cars. With sodium ion and high density LFP chemistries coming to mass production this year, ICE cost advantage's days are numbered. Supply constraints will keep ICE marginally cheaper for probably 5 years in some consumer car classes.

But "far less utility for a higher price and more inconvenience" is pretty much bunk. But I would keep an ICE if I was in the Midwest.

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

#165

Post by AtlasBarfed »

CamperBob2 wrote: post #64
linuxftw wrote: post #21

Earlier quoted context omitted.

I remain skeptical until the products are real and affordable. No reason to buy an electric car now if they'll have potentially double the range in a few years.

Yet another problem that could have been avoided if government had had the foresight to enforce a technology-agnostic swappable battery standard.

The only real practical version of this would be an additional range extension battery that is towed. Or synthfuel+generator, or even hydrogen (and man, this is like the ONLY time I ever can see practical use of hydrogen). Which is also an effective strategy for semis / RVs / towing with EVs.

The way to get best range+efficiency out of an EV these days is cell-to-pack where the pack is basically integrated into the frame. I think it's on the order of 20% better range for 10-20% lower production cost. There's no way a standardized swap pack could match the engineering numbers of that, which makes it an economic no-go.

And by the time the swap standard was implemented, demonstrated, and platforms changed to it, it would be 10 years. Batteries with this tech, sulfur, alu-air, etc will triple the density for half the current cost by then. An EV will go 800 miles on a pack that is 2/3 or 1/2 the size/weight, and remember there's a pseudo-rocket equation on these big battery packs.

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

#166

Post by sandermvanvliet »

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...?

My Land Rover Defender had the battery under the seat as well.

But hey, there are so many holes in the car it’s basically permanently venting…

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

#167

Post by morepork »

canoebuilder wrote: post #6

> 750 Wh/kg is great. To put it mildly. Energy density in the current leaders in that category, lithium ion batteries, 250-270 wh/kg. So, provided a similar or better ratio of watt-hours to unit of volume, we’re basically looking at tripling the energy storage of EVs or significant weight reduction, in the ideal scenario of this design being a safe and cost effective replacement for current batteries.

Because weight affects range, you could keep the same amount of energy and increase range at the same time as the battery would only weigh 1/3 as much and be maybe 400kg lighter

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

#168

Post by morepork »

majormajor wrote: post #45
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.

Are there any EVs with Honda Civic or Accord or BMW 2 series weight? E.g. <3500lb? Even a Leaf seems to start at 3500lbs now.

BYD Dolphin is 1285-1450 kg depending on which options you pick, which is in that range

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

#169

Post by janalsncm »

gorjusborg wrote: post #123
CamperBob2 wrote: post #64

Earlier quoted context omitted.

Yet another problem that could have been avoided if government had had the foresight to enforce a technology-agnostic swappable battery standard.

You got it, swappable batteries is the key to EV mass-adoption. Do people care about range with internal combustion vehicles? Not really, if they can get between gas stations. It takes very little time to refill, and each vehicle (regardless of manufacturer) uses the same stuff. The trouble is that standardizing when there is hot competition is very political. Things need to cool down a little before it can be done,…

> You don't want government to get involved early when engineering is involved.

Apple would argue the EU was stepping on their toes by imposing USB-C. Maybe whatever proprietary connector Apple comes up with is better in some technical ways. But that benefit has to be weighed against the emergent benefits of standardization.

Maybe 120V AC isn’t objectively the best. But isn’t it nice you don’t have to think about it before plugging into a wall? I think so.

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

#170

Post by mdekkers »

npunt wrote: post #144
solardev wrote: post #141

Earlier quoted context omitted.

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

Possibly for a Carrera, but for a Cayenne? Despite the Porsche brand, that isn’t anywhere close to a sports car. The platform is shared with the Audi Q7 and the VW Touareg. It’s a tractor with nicer seats. The weight of a battery fitting under a driver seat would be similar to a big shopping run, so weight distribution wouldn’t have been a consideration.

Manufacturing logistics probably played a bigger role.

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