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Tell HN: I think I found Toyota's battery

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121–130 of 211 posts

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

#121
post #82

Earlier quoted context omitted.

The floor for EVs is very high. In Europe people frequently buy compact cars. Let's take VW Golf as an example. The lightest version of the current model weighs 1300kg, more or less. The EV equivalent, ID.3, weighs 1800kg. That's 500kg extra (!) which is almost 40% more. That's an insane amount of extra weight for a small car. The percentage difference becomes less for bigger cars, so I imagine that's why some Americ…

Meanwhile, the BMW i3 weights between 1245 kg to 1441 kg, depending on configuration, battery size, and presence of optional range extender engine, showing what is possible when companies bother to optimize for weight savings.

The i3 is a carbon finer tub design which is both extremely expensive and not uniquely applicable to EVs. It's a very cool design but its an extreme outlier and it isn't a realistic bar to compare against for companies trying to make money on mass market vehicles.

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

#122

> 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.

Current lead acid batteries can do this as well. Smells awful and pretty unsafe situation. H2S is quite dangerous but it’s rare that they’d create an IDLH situation as long as there’s a bit of breeze.

i'd be surprised if lead-acid batteries produce detectable quantities of hydrogen sulfide; isn't their sulfur bound up in an extremely stable oxoanion? still, https://web.archive.org/web/20161005164308/http://www.wesh.c... certainly doesn't sound like sulfuric acid

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

#123

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.

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, and you don't want to standardize until designs naturally converge.

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

EVs will be a pain until a standard emerges though. I can't wait until I can drive up to a station and get a pre-charged battery.

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

#124

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.

I guess it can be. To me it's more for calling attention to a current event (api shutting down, breaking changes at a service, privacy concern, etc). Kind of like a PSA. Using it as a blog post feels inappropriate to me.

But checking the guidelines and FAQ, there doesn't seem to be anything to actually imply that it can't be used that way.

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

#125
post #13

> 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.

At that energy density, can't they just wrap the entire smaller battery in 2 layers of ceramic and steel or something and just side-step the entire safety discussion OP is mentioning? Yes, I know it's probably a silly solution :-)

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

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

#126

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.

Not really, I treat it more like a forum.

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

#127

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,…

My thinking was always that the physical packages should be standardized -- think two 'AA's for a Miata and twenty 'D's for a Peterbilt -- along with the connectors. Also a rudimentary bus protocol to communicate the battery's parameters to chargers and loads, store usage history, keep track of expected remaining life, and such. But literally nothing else other than basic environmental and safety considerations. A battery must be recyclable in some form or fashion, will not usually set your house on fire, cannot explode under normal operating conditions, cannot emit more than X milliroentgens per hour, whatever. Other than that, no rules.

Don't standardize the chemistry, or the voltage, or the current limit, or the charging rate, or anything else... just make it fit. Then require the industry to adopt standardized power converters and chargers under similar auspices. For the hardware, don't specify voltage, don't specify cost, don't specify charging time, don't mandate anything except the ability to charge a particular class of battery.

Simply mandating the form factor, connector, and handshaking could have made all the difference. We would have manufacturers competing to see who could build the most economical and/or performant batteries, chargers and converters. Charging could take place at times and places that optimize efficiency. Filling up an EV could take less time than getting gas, not more. And there would be no chicken-and-egg problem to impede adoption, as we're seeing now. You would not be stuck with the batteries or the charger that your car came with.

We will kick ourselves for the next 50 years for not doing this.

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

#128

> 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…

As excited as I am, there are some kinks in the supply chain that may need some extra taking care of [1]. Although this incident involved relatively few electric vehicles on open sea, it would be even more difficult to contain with larger shipments. Modular battery installations and separate fireproof(ed) shipping are options that need to be considered.

[1]: https://apnews.com/article/cargo-ship-fire-netherlands-envir...

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

#129

This will be neat if it works but really there isn't going to be a huge market for 500+ mile cars vs the cost savings of getting a 300-400 mile car. The exception might be road-trippers and people who do a lot of towing but I suspect that is a much smaller population than people tend to think.

What are you on? Having battery with 3x battery capacity will be an absolute game changer. This will do a lot of good, if it gets into production. For one thing, it will make EVs competitive with diesel, which will be s huge win for getting us of oil.

People will absolutely choose the longer battery span to rid themselves of range anxiety. I agree, it’s a terrible take.

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

#130

This will be neat if it works but really there isn't going to be a huge market for 500+ mile cars vs the cost savings of getting a 300-400 mile car. The exception might be road-trippers and people who do a lot of towing but I suspect that is a much smaller population than people tend to think.

Real world usage is you only get to use ~70% of the stated range on a road trip, so we're really talking about 350 miles of range, which is, as you say, what most people actually want.

Why 70%? You obviously don't run the battery to zero, 10% is a common amount of buffer to leave. And then when you DC fast charge, the rate of charging drops dramatically around 80%, so people don't charge to full.

These are for ideal conditions, add in any sort of weather and the range drops again as you run a heater, etc.

Living in the Bay Area, driving to Tahoe in the winter without a mandatory recharge should be the gold standard.

It's not an unusual use case, "only" about 180 miles, and yet there aren't any EVs that can do it confidently because going uphill in the cold with aerodynamic-destroying ski rack is really hard.

A car with 500 miles of fair-weather range could probably do it?

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