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Why is everyone trying to build a solid-state battery?

construction-physics.com

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Re: Why is everyone trying to build a solid-state battery?

#201

Post by NovemberWhiskey »

heckintime wrote: post #185
hannasanarion wrote: post #55

Earlier quoted context omitted.

For disposable applications like that, aren't there single-use chemistries that are better already? I'm thinking by analogy to things like: - WW2 proximity fuzes that had batteries where the electrolyte was in a vial that got smashed by the G-forces of being shot out of a cannon providing power to the radio inside for the 10 seconds it needs to get to the incoming aircraft - Hearing aid Zinc-Air batteries, that are e…

Not all drones are one way

Even for drones that are reusable: if there’s a substantial performance advantage to using a primary cell then you might just want to do that if you’re relatively price insensitive and have good logistics (say, the US Army). Or if you need to be self-sustaining in non-permissive environments (say, the US Army).

Re: Why is everyone trying to build a solid-state battery?

#202

Post by oskarkk »

JoshuaDavid wrote: post #193
saltcured wrote: post #79

Earlier quoted context omitted.

The previous point is fair though. What is the energy density of gasoline in a stoichiometric mixture with its oxidizer and not already detonated? That's where TNT beats it by a long shot. The mixture with any chance of being stored would be some relatively low pressure gas. Edit: Or, a fair closed-system comparison to a battery would need to include a liquid oxygen tank or similar so you have the two components stor…

Gasoline + LOX beats TNT on energy density per unit mass and per unit volume, no? There's a reason that kerosene+h2o2 is a classic rocket fuel, and TNT is not.

It's usually kerosene + O2, not H2O2. But H2 + O2 is another classic liquid rocket fuel that has higher specific energy (energy per mass), but lower energy density (energy per volume) than kerosene, and is used mostly as a 2nd stage fuel (where mass is most important). Its lower density and the need to keep it very cool mean heavier tanks, and it's also hard to work with due to being such a small molecule that likes to leak, which causes development costs to be higher.

Re: Why is everyone trying to build a solid-state battery?

#203

Post by jhallenworld »

qwery wrote: post #83

If you know a bit about electronics, you might be a bit surprised by the term 'solid-state battery'. It's a poor analogue to the more common usage of solid-state with semiconductors, integrated circuits, etc. -- a "solid-state" cell is still a chemical cell. It's not a paradigm shift on the level of, say, replacing a relay with a MOSFET.

I think "solid-state" is a marketing term which means you need to use Fermi-Dirac statistics to model your device, vs. vacuum tubes where you can use Maxwell-Boltzmann statistics. I think you can use Maxwell-Boltzmann at least for the ions in the electrolyte.. but maybe have to use for Fermi-Dirac for all conductors in a solid-state battery.

Re: Why is everyone trying to build a solid-state battery?

#204

Post by zuzululu »

thelastgallon wrote: post #200
zuzululu wrote: post #199

Earlier quoted context omitted.

I'm surprised they didn't flag and downvote you. There seems to be a certain crowd that seems view EV as sort of a panacea without considering the true realities which involve experience and research to know they are far from replacing ICE

If ICE is the only vehicle for you, because of religious reasons, thats okay. There are large and small countries ( China, Norway) that have majority EV cars and continue to grow. There are 120+ other countries that are buying EVs. Even in US, there are a few people who have bought EVs and realized it works for them. A person who really needs an ICE car would encourage others to buy EVs because it would reduce oil de…

> If ICE is the only vehicle for you, because of religious reasons, thats okay

so you admit EV is a cult if ICE is a religion ? that's not okay.

Re: Why is everyone trying to build a solid-state battery?

#205

Post by [deleted] »

hannasanarion wrote: post #55
GlibMonkeyDeath wrote: post #18

The article gives the technical reasons that answer the headline question (e.g. potential for better energy density) I am surprised they didn't point out the literal "killer app" - military drones. Energy density is king for any airborne power source. And dendrite growth during charge/discharge cycling isn't as big a deal for that application (how many times would you need to charge a disposable weapon?)

For disposable applications like that, aren't there single-use chemistries that are better already? I'm thinking by analogy to things like: - WW2 proximity fuzes that had batteries where the electrolyte was in a vial that got smashed by the G-forces of being shot out of a cannon providing power to the radio inside for the 10 seconds it needs to get to the incoming aircraft - Hearing aid Zinc-Air batteries, that are e…

[deleted]

Re: Why is everyone trying to build a solid-state battery?

#206

Post by GuB-42 »

himata4113 wrote: post #10
laxisOp wrote: post #6

We need way more research on batteries. People cant ingine what is possible if we make battery 10x energy dense.

I don't think 10x density is possible without getting into nuclear, at least not with the chemistries we know of today, everything at a certain point becomes an explosive. Speaking of nuclear, getting tons of the material that powers mars rovers and putting them in every home would generate enough power for decades... At the cost of being able to build a nuclear bomb in a garage.

The problem with the stuff that powers mars rovers (RTG) is that gives off constant power. If your RTG gives off 100W, you will always get 100W, no more, no less, until it progressively decays on the scale of decades. You can't even turn it off.

The energy density is great, but the power density is really bad. For most applications, you still want a battery in addition to the RTG.

I don't know how easy it is to make a nuclear bomb from them, it is not the right isotope. You can probably make a nuclear exploding thing, like a dirty bomb, but not the nuclear bombs we know.

Re: Why is everyone trying to build a solid-state battery?

#207

Post by alok-g »

Can someone please explain why electrons also cannot go directly through the electrolyte just like Lithium ions? Footnote 1 skips explaining this. I tried asking ChatGPT, but it is not getting to a complete answer. It says things that just pushes the question into another form.

Re: Why is everyone trying to build a solid-state battery?

#208

Post by Shitty-kitty »

alok-g wrote: post #207

Can someone please explain why electrons also cannot go directly through the electrolyte just like Lithium ions? Footnote 1 skips explaining this. I tried asking ChatGPT, but it is not getting to a complete answer. It says things that just pushes the question into another form.

An ion is a atom that has lost electrons and thus it has a + charge. The electrons are the - charge. The electrolyte allows + to flow but not -

Re: Why is everyone trying to build a solid-state battery?

#209

Post by cyberax »

SV_BubbleTime wrote: post #198
rogerrogerr wrote: post #172

Earlier quoted context omitted.

And you mostly aren’t charging to 80%, usually it’s closer to 40-60%.

heh, ok, that’s strange. So when you say it’s got a 350 mile range, but then make the point you only need to charge to 40% that you would be fine with a single vehicle that had a 140mile range? I swear buying an EV in 2026 breaks brains. The push back has been so bad because the mfgs pushed the single car lie… but the people that jumped in now need to defend their $60,000 purchases. I get it, but please don’t think y…

> “5-10 minutes every two hours” … lol, that’s good when you’re going from LA to San Diego. If I had to stop every two hours on a road trip I’d get a train ticket, it would feel a lot faster.

Sorry, now you're spewing nonsense. LA to SD does not require charging at all.

I did more than 120000 miles of road trips in my EVs across the US and Canada, even before they were fully covered with charging networks. So I know a thing or two about that.

A good way to think about charging is not in kilowatts but in miles per hour. Tesla Model 3 peak charging rate is 1000 miles per hour, and the average on 10-80% is around 600 mph. The state-of-the-art Chinese cars can charge at 3000 miles per hour and more than 1200 mph on average.

So if you want to do a 500-mile road trip (~8 hours of driving), that's about 45 minutes of charging time for a Tesla and less than 30 minutes for modern Chinese cars.

But wait, there's more! For a 500-mile road trip, you will have at least 200 initial miles covered by your home charging or if you stay overnight in a hotel with a charging station. So that's even less time spent charging.

And yeah, people usually prefer to do more frequent charges rather than drawing the battery down to 10% to alleviate the range anxiety and just as a safety buffer.

Re: Why is everyone trying to build a solid-state battery?

#210

Post by alok-g »

Shitty-kitty wrote: post #208
alok-g wrote: post #207

Can someone please explain why electrons also cannot go directly through the electrolyte just like Lithium ions? Footnote 1 skips explaining this. I tried asking ChatGPT, but it is not getting to a complete answer. It says things that just pushes the question into another form.

An ion is a atom that has lost electrons and thus it has a + charge. The electrons are the - charge. The electrolyte allows + to flow but not -

Cool! That seems to fit as the voltage build-up (assuming no current taken from the battery) is not reversed by the negative ions flowing backwards.

I still have the question though. How does the electrolyte do that? :-)

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