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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?

#191

Post by dredmorbius »

vikramkr wrote: post #36
thechao wrote: post #23

Earlier quoted context omitted.

Gasoline has 10x the energy (MJ/Kg) than TNT, but it's not a "bomb". Being a "bomb" is about energy release rate . A battery is still controlled by its chemistry.

Liquid gasoline does not have anywhere near the energy of TNT, or even a battery for that matter. It contains basically zero releasable energy. It needs oxygen or another oxidizer to react with to actually release any energy. TNT and batteries' energy density calculations include the oxidizer and the oxidizer is in close proximity to the fuel (molecularly so in the case of TNT). If you 10x the "energy content" of gas…

Energy capacity vs. energy release rate, or energy vs. power, tends to follow an inverse relationship, at least within similar domains.

The fuels which afford the highest rates of storage tend to release it more slowly. Chemical explosives typically have about 1/10 the energy storage capacity (by mass) of fuels, as several people have pointed out.

Similar relationships exist for other forms of energy storage. For electricity, fuel cells, chemical cells ("batteries"), flywheel / reaction storage, and capacitors tend to offer a trade-off between total storage capacity and reaction time. Capacitors can react at intra-phase rates (that is, within a single 60Hz power cycle), whilst batteries and flywheels can take longer to come online.

See for example: "Battery Parameters" https://www.monolithicpower.com/en/learning/mpscholar/batter...>.

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

#192

Post by dmix »

laxpri wrote: post #177
dmix wrote: post #34

Earlier quoted context omitted.

The article says $4B was put into solid state research/companies as of 2025 in the US alone. Seems like they are working on it

maybe, but not enough. but if there is level 1 to 10 and the chips are level 10, from transistor to today. the battery would be level 2-3 . if this continues the battery cant keep up with more advance tech,where energy density matters like flying cars,BCI etc . like people are selling two same products to the same person(same time), because the battery life is bad.

I'm all for more

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

#193

Post by JoshuaDavid »

saltcured wrote: post #79
csours wrote: post #68

Earlier quoted context omitted.

It's an interesting discussion, because if you assume access to atmospheric oxygen, gasoline is MUCH more energy dense. TNT.....: 4 kJ/gram and 7 MJ/liter Gasoline: 43 kJ/gram and 33 MJ/liter

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.

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

#194

Post by SV_BubbleTime »

heaney-555 wrote: post #115
zuzululu wrote: post #112

Earlier quoted context omitted.

uphills + cold/hot climates, the ranges won't be able to compete with ICE. its basic physics. cold uphill still reduces charging speed, available power, and range, while sustained heat accelerates degradation. Thermal-management systems mitigate those weaknesses by consuming energy and adding cost, weight, and complexity. meanwhile ICE has gotten ridiculously clean and efficient over the years it is more efficient at…

The latest battery chemistries perform incredibly well in cold and hot climates. Internal combustion is not clean, and is inherently significantly less efficient than an electric motor. Also, LFP chemistries are incredibly safe compared to NMC, which is what you're concerned about in terms of thermal runaway. ICE is mostly stagnant tech. Meanwhile EV tech is rapidly improving!

> The latest battery chemistries perform incredibly well in cold and hot climates.

Oh? Show me a model of EV that has it is going to lower capacity battery heating and cooling systems.

I’m an automotive EE… I can’t name any. I’m working on things that will go in 2032 vehicles. Surprise, most are ICE, but of the EV vehicles the battery protection systems are becoming more rugged, not less.

Where does your supposition come from?

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

#195

Post by mathgeek »

SV_BubbleTime wrote: post #138
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…

Air is usually quite available though.

Many batteries are sealed specifically for this reason.

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

#197

Post by mathgeek »

moffkalast wrote: post #153
K0balt wrote: post #123

Earlier quoted context omitted.

A snickers bar has nearly 5× TNT’s energy per kilogram—TNT merely has the habit of being extremely impatient about releasing it.

I'm still surprised we haven't figured out a bioreactor you can feed your scrap food and turn it into energy, methane combustion notwithstanding. Like imagine feeding a roomba some sugar and it's set for a few days lol.

You could probably even power a time machine without needing plutonium.

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

#198

Post by SV_BubbleTime »

rogerrogerr wrote: post #172
vablings wrote: post #165

Earlier quoted context omitted.

"This is such a euphemism to pretend that you’d like to wait two hours at a refueling station." There is virtually no EV sold on the market today that takes two hours to charge to 80% at a HVDC charger. "I get it; I like EVs for their around town purpose, but man it’s almost fantasy to sell it as “5-10 minutes every two hours”." The Hyundai Ioniq 5 takes about 20 minutes to go from 10% SOC to 80% SOC in about 18 min…

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 you guys are sneaky about it. We all know what it is.

“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.

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

#199

Post by zuzululu »

SV_BubbleTime wrote: post #194
heaney-555 wrote: post #115

Earlier quoted context omitted.

The latest battery chemistries perform incredibly well in cold and hot climates. Internal combustion is not clean, and is inherently significantly less efficient than an electric motor. Also, LFP chemistries are incredibly safe compared to NMC, which is what you're concerned about in terms of thermal runaway. ICE is mostly stagnant tech. Meanwhile EV tech is rapidly improving!

> The latest battery chemistries perform incredibly well in cold and hot climates. Oh? Show me a model of EV that has it is going to lower capacity battery heating and cooling systems. I’m an automotive EE… I can’t name any. I’m working on things that will go in 2032 vehicles. Surprise, most are ICE, but of the EV vehicles the battery protection systems are becoming more rugged, not less. Where does your supposition…

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

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

#200

Post by thelastgallon »

zuzululu wrote: post #199
SV_BubbleTime wrote: post #194

Earlier quoted context omitted.

> The latest battery chemistries perform incredibly well in cold and hot climates. Oh? Show me a model of EV that has it is going to lower capacity battery heating and cooling systems. I’m an automotive EE… I can’t name any. I’m working on things that will go in 2032 vehicles. Surprise, most are ICE, but of the EV vehicles the battery protection systems are becoming more rugged, not less. Where does your supposition…

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 demand, and with demand destruction, considerably lower oil prices. With lowered demand, Saudi Arabia can supply a barrel for $5 - $10/barrel from Ghawar Field. Which means a gas-head who commutes every day from Yukon, Canada to Guadalajara, Mexico has a significantly lower gas bill.

The only people who wants everyone to buy ICE are fossil fuel shills.

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