Why is everyone trying to build a solid-state battery? • Hacker News Board

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

#161

Post by rogerrogerr » Thu, Jul 30, 2026, 6:43 PM UTC

SV_BubbleTime wrote: post #147

rogerrogerr wrote: post #53

Earlier quoted context omitted.

Yeah, when I take a road trip I genuinely enjoy the cadence of charging. 5-10 minutes every two hours, just enough to go to the bathroom or walk around. I get to my destination not materially later, and feeling far more relaxed than when I was doing death marches in a gas car.

This is such a euphemism to pretend that you’d like to wait two hours at a refueling station. Anyone who’s ever driven between Seattle and Portland and seen the e16b charging lots of people sleeping in their cars knows there is a whole different side to your rosey picture. EV owners are still internalizing their range anxiety into a benefit. I get it; I like EVs for their around town purpose, but man it’s almost fant…

> This is such a euphemism to pretend that you’d like to wait two hours at a refueling station.

What? I said no such thing. I would hate to wait two hours at a refueling station.

> it’s almost fantasy to sell it as “5-10 minutes every two hours”.

I guess I live in fantasy land then.

Maybe the non-Tesla charging story is crap, but I made conscious choices not to participate in that circus.

I have no range anxiety. I point the car where I want to go, it tells me where to charge and for how long, and it’s earned my trust over many road trips. It hasn’t been wrong yet.

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

#162

Post by ianburrell » Thu, Jul 30, 2026, 6:43 PM UTC

tflinton wrote: post #69

clickety_clack wrote: post #17

Earlier quoted context omitted.

I think people can imagine lighter cars and laptops and things. Is there something bizarre that’s unlocked like battery powered space launches or something?

High density batteries allows us to have dramatically cheaper electricity. Think of it like this, what happens when electricity is 1/10th the cost? Beyond what others have pointed out (electric airplanes, cars that drive thousands of miles), costs for everything would drop as energy is a core driver of it in every good you consume. If you can pull energy where it's very cheaply available and store/transport it anywhe…

Energy density doesn't matter for electricity since the storage batteries don't move and there is plenty of space for them. Cost per energy stored is what matters. Density is important for transportation especially planes.

Sodium ion batteries have worse energy density than lithium ion but they have potential to be cheaper and more reliable. Iron air batteries have poor round trip efficiency but could be even cheaper.

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

#163

Post by vablings » Thu, Jul 30, 2026, 6:49 PM UTC

capitainenemo wrote: post #158

SV_BubbleTime wrote: post #142

Earlier quoted context omitted.

Uh… gasoline has a super high vapor pressure. If you start out at the wrong ratio, it does what it can to make that ratio right. I’ve seen a few gasoline fires that start by burning, and then much more rapidly expressing potential.

Requires a good mix though. The parent is still correct. Mythbusters spent a long time trying to get cars to blow up in a dramatic hollywood fashion in various episodes and determined that under most conditions it wouldn't happen. They did get it to happen, they just had to try really hard. In most accidents the gas tank will not blow up.

High velocity accidents where the gas is quickly dispersed into the air is pretty much the only way that happens.

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

#164

Post by orliesaurus » Thu, Jul 30, 2026, 6:50 PM UTC

SV_BubbleTime wrote: post #146

piquadrat wrote: post #72

Earlier quoted context omitted.

Your Polestar 2 battery is based on battery technology that is 5+ years old. Right now you can buy a BYD car in China that charges at up to 1500kW - close to 10x the peak charging rate of a Polestar 2.

I’m an automotive EE… I find particular interest when someone mentions BYD as what “works” in electric vehicles. Wild fucking west right there.

I'd love to learn more about this.

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

#165

Post by vablings » Thu, Jul 30, 2026, 6:56 PM UTC

SV_BubbleTime wrote: post #147

rogerrogerr wrote: post #53

Earlier quoted context omitted.

Yeah, when I take a road trip I genuinely enjoy the cadence of charging. 5-10 minutes every two hours, just enough to go to the bathroom or walk around. I get to my destination not materially later, and feeling far more relaxed than when I was doing death marches in a gas car.

This is such a euphemism to pretend that you’d like to wait two hours at a refueling station. Anyone who’s ever driven between Seattle and Portland and seen the e16b charging lots of people sleeping in their cars knows there is a whole different side to your rosey picture. EV owners are still internalizing their range anxiety into a benefit. I get it; I like EVs for their around town purpose, but man it’s almost fant…

"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 with an 800v charger. That equates to about 3 hours of driving on the highway.

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

#166

Post by vablings » Thu, Jul 30, 2026, 6:58 PM UTC

Sohcahtoa82 wrote: post #148

thelastgallon wrote: post #94

Earlier quoted context omitted.

An EV doesn't need to have 480 miles of range. Nobody is driving that distance daily. 98% of trips are under 50 miles. Only 0.8% of the trips are over 100 miles! Also, EVs use regenerative braking. That should help a little bit. EVs should be built with 100 - 150 mile range. All families with 2 cars can immediately switch one of their cars to a daily driver EV and the other vehicle is a minivan. There are lots and lo…

> EVs should be built with 100 - 150 mile range. [..] if they need to go longer, US has a robust rental car industry As an EV owner myself, no. Absolutely not. The reason is simple: The mere existence of low-range EVs hurts overall EV adoption , because people aren't going to rent a car just for a road trip. You're talking about adding $100+ per day on what's supposed to be a cheaper method of travel compared to flyi…

"The reason is simple: The mere existence of low-range EVs hurts overall EV adoption, because people aren't going to rent a car just for a road trip. You're talking about adding $100+ per day on what's supposed to be a cheaper method of travel compared to flying."

Just wait for people to be priced out of ICE cars. EV's should be and will be significantly cheaper to buy and manufacture.

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

#167

Post by fhn » Thu, Jul 30, 2026, 7:18 PM UTC

m463 wrote: post #85

MarkusQ wrote: post #81

> because the liquid electrolyte currently used in batteries is flammable, replacing it with a solid could make batteries safer and less susceptible to fire. The problem is primarily that batteries are storing a lot of energy, which can be released when things go wrong. The electrolytes (technically, the solvents) typically don't ignite under 750°F or so, which makes them less flammable than a lot of other common mat…

I wonder about the youtube videos of someone driving a screwdriver through a battery pack. Is that the electrical discharge, then the lithium going off, then the electrolytes?

you ever short a car battery? That much electricity running through metal will create a lot of heat which then ignites the lithium. Watch a video on thermite and you'll get the idea.

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

#168

Post by fhn » Thu, Jul 30, 2026, 7:21 PM UTC

gabrielhidasy wrote: post #59

mb7733 wrote: post #28

Earlier quoted context omitted.

> We can extract a lot more energy from fossil fuels in large scale plants This isn't true at all for natural gas. Burning it for heat in the home is much more efficient than burning it in a plant, converting it to electricity, transferring that electricity, then turning that electricity into heat.

Depends, if you are turning that electricity into heat using a heat-pump you might win on most situations (maybe lose if the weather is really cold outside, unless you add geothermal loops, but then its a lot more expensive to make)

No it wouldn't depend. Electricity generation and electricity transfer has losses. Gas transfer has loss only if there is a leak.

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

#169

Post by [deleted] » Thu, Jul 30, 2026, 7:30 PM UTC

mekdoonggi wrote: post #22

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?)

If the thing is going to blow up anyway, does it need to be light? Wouldn't you rather have more cheaper drones?

[deleted]

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

#170

Post by kazinator » Thu, Jul 30, 2026, 7:35 PM UTC

Sohcahtoa82 wrote: post #148

thelastgallon wrote: post #94

Earlier quoted context omitted.

An EV doesn't need to have 480 miles of range. Nobody is driving that distance daily. 98% of trips are under 50 miles. Only 0.8% of the trips are over 100 miles! Also, EVs use regenerative braking. That should help a little bit. EVs should be built with 100 - 150 mile range. All families with 2 cars can immediately switch one of their cars to a daily driver EV and the other vehicle is a minivan. There are lots and lo…

> EVs should be built with 100 - 150 mile range. [..] if they need to go longer, US has a robust rental car industry As an EV owner myself, no. Absolutely not. The reason is simple: The mere existence of low-range EVs hurts overall EV adoption , because people aren't going to rent a car just for a road trip. You're talking about adding $100+ per day on what's supposed to be a cheaper method of travel compared to flyi…

Not only that, but with a longer range, you have more flexibility in planning recharging. It may take more time to top up from 50 km left to 500 km, but you have more flexibility about when to do it. Something that needs a daily charge is going to be interfering with your schedule.