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Solid-State Battery Has 2x the Energy–and No Anode

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131–140 of 218 posts

Re: Solid-State Battery Has 2x the Energy–and No Anode

#131
post #61

Earlier quoted context omitted.

> Well H2 is a hedge. It's a green-ish fuel and has potential as a replacement to lng for japan. Is it though? Can't be a hedge if it doesn't really work well fundamentally. Although I'll admit to being largely ignorant of the Japanese car market. IMO, it'd be much more practical to invest in automotive LNG tech and combine that with synthesizing LNG from the atmosphere (or at least developing the tech to do so). Pra…

H2 has the benefit of being much easier to store, transport and transfer than batteries. It’s able to be stored in small containers and large vessels of any shape. Batteries manufacturing is much more complex. Electricity needs to be transferred from a power station over wires, while hydrogen can be pumped into a vehicle from a bulk source. Sure H2 is dangerous, but so is LNG, and petrol for that matter. 100+ years o…

Nah.

I worked as a project engineer in a hydrogen fuel cell test lab for a few years. H2 is EXTREMELY hazardous. It can be ignited by a miniscule amount of energy (i.e. a tiny static spark will do it), and it has a very fast flame front, which creates an extremely energetic explosion. It's also the smallest molecule, so it's very difficult to prevent leakage, and it embrittles and degrades most steels over time. Additionally, proton exchange membrane fuel cells (the most common kind) are poisoned by anything NOT H2, so you can't add odorous agents to H2 to easily detect leaks, like we do with natural gas. H2's only non-dangerous characteristic is its high buoyancy, which means it dissipates quickly in outdoor environments, but in my opinion that is not sufficient to offset all of its other dangerous characteristics.

I would NEVER live in a building that had H2 stored inside (as in, inside a vehicle tank) or pumped in it, and I would definitely not trust the general public to use it safely.

It also has to be stored at either incredibly high pressures (as a gas) or incredibly cold temperatures (as a liquid), neither of which are conducive to large-scale, long-range transport.

But the worst part of H2 isn't how dangerous it is or how impractical it is; the worst part of H2 is how incredibly inefficient a hydrogen economy would be. See Paul Martin's excellent summary of H2 for a thorough debunking of the main H2 talking points.

https://www.linkedin.com/pulse/distilled-thoughts-hydrogen-p...

Re: Solid-State Battery Has 2x the Energy–and No Anode

#132
post #96
post #94

Earlier quoted context omitted.

> For example, a Chevy Bolt has a lithium ion battery to power the drivetrain and a conventional lead-acid battery for the accessories. This seems like an odd choice - unless you already bought a supply of lead-acid batteries for the next 50 years or so. I've read about a car using supercapacitors in the regenerative brakes to capture energy at high current and, then let it trickle back into the main batteries (or dr…

This is a classic, it isn’t broken don’t fix it situation. Many laptops had both a lithium ion battery and a watch battery used to keep the bios and an internal clock running after the battery died. https://www.makeuseof.com/tag/why-does-my-motherboard-have-a...

That was a bit of a necessity. Users wouldn’t want their clock to reset when they swapped batteries, and you couldn’t be sure the machine was connected to a time server to set the time at boot.

Re: Solid-State Battery Has 2x the Energy–and No Anode

#133
post #63

Lithium ion batteries set the standard because they have an acceptable level of all the key metrics: energy storage by weight; energy storage by volume; discharge rate; charging rate; production costs. Every single one of these big breakthrough announcements touts how great this new tech is- in just one or two particular metrics. The problem is that Li-Ion batteries are just barely acceptable in all of those metrics.…

Lithium ion batteries are not a single technology and are not static. There are periodic changes that improve the batteries in various dimensions. They are constantly evolving. At the same time, it is perfectly feasible for EVs to switch to alternate chemistries a construction methods. Individual vehicles might not switch but a manufacturer could switch their product line to start using sodium or sulphur or whatever new chemistry comes along.

This Ars story talks about the ongoing improvements to battery tech… https://arstechnica.com/science/2021/05/eternally-five-years...

Re: Solid-State Battery Has 2x the Energy–and No Anode

#135
post #69
post #61

Earlier quoted context omitted.

H2 has the benefit of being much easier to store, transport and transfer than batteries. It’s able to be stored in small containers and large vessels of any shape. Batteries manufacturing is much more complex. Electricity needs to be transferred from a power station over wires, while hydrogen can be pumped into a vehicle from a bulk source. Sure H2 is dangerous, but so is LNG, and petrol for that matter. 100+ years o…

The bait-and-switch is that while green hydrogen can be made, it very rarely is, and when it is, it's less cost-effective than a battery electric solution. It's almost always a Trojan horse for shifting carbon emissions away from the tailpipe to a refinery where you can't see them quite as obviously.

That is no different than a battery car. You are just shifting pollution to whatever is making your electricity. And if anyone comes in and says "I spent tens of thousands of dollars getting green electricity!" then it should be obvious that the same level of spending could make upstream hydrogen production vastly greener.

And no, it is not "less cost effective" because batteries involve dramatically higher upfront production costs. The argument is really just a troll argument and virtually identical to the same arguments used against battery cars.

Re: Solid-State Battery Has 2x the Energy–and No Anode

#136
post #63

Lithium ion batteries set the standard because they have an acceptable level of all the key metrics: energy storage by weight; energy storage by volume; discharge rate; charging rate; production costs. Every single one of these big breakthrough announcements touts how great this new tech is- in just one or two particular metrics. The problem is that Li-Ion batteries are just barely acceptable in all of those metrics.…

Actually, energy storage by weight is not as big a deal for electric cars. Regenerative braking can recover most of a vehicles kinetic energy, which is where the weight dependent energy goes. This is why several hybrids get better fuel economy in city driving than highway, the biggest losses are due to aero which increases nonlinearly with speed. Otherwise yes, it's important to find something better without sacrific…

>Regenerative braking can recover most of a vehicles kinetic energy

I used to think that was the case, but then i think i read somewhere that it only recovers 20% of the kinetic energy. Can't find it anymore though

Re: Solid-State Battery Has 2x the Energy–and No Anode

#137
post #6

Solid state might share the fate of Betamax. There was a post a while ago about a small scale battery manufacturer named Amprius, which reported 500Wh/kg batteries: https://news.ycombinator.com/item?id=35276709 Thing is, the company is producing 450Wh/kg batteries NOW and they're planning on scaling up their manufacturing capacity to 5GWh: https://www.convertingquarterly.com/ConvertingQuarterly/Indu... This solid sta…

EVs are already very heavy, and when the model 3 switched to LFP it got even heavier. This mass has lots of subtle consequences that aren't always appreciated. Like accelerated tire wear (which Tesla owners notice after they buy) and increased particulate pollution from that, increased road wear, increased danger to pedestrians and cyclists, etc. So, I'm less excited about LFP. There are a number of ideas in the work…

> increased danger to pedestrians and cyclists, etc.

Why do seemingly so people here understand clipping functions?

The lethality of a pedestrian-vehicle collision with a 4,000lb vehicle at 60MPH and a 400,000lb vehicle at 60MPH are both 1

In practical terms, the additional weight of an EV has zero effect on pedestrian collision lethality, whereas something like bumper design would.

Re: Solid-State Battery Has 2x the Energy–and No Anode

#138
post #113

Earlier quoted context omitted.

One drawback of using lots of lithium batteries in your home is that they might experience thermal runaway and burn your house down. Not having to worry about that should have some additional value.

Most new solar installations now use LiFePO4 which apparently is much safer on that runaway side...

Also way better cycle life, but the density is slightly lower.

Re: Solid-State Battery Has 2x the Energy–and No Anode

#139
post #6

Solid state might share the fate of Betamax. There was a post a while ago about a small scale battery manufacturer named Amprius, which reported 500Wh/kg batteries: https://news.ycombinator.com/item?id=35276709 Thing is, the company is producing 450Wh/kg batteries NOW and they're planning on scaling up their manufacturing capacity to 5GWh: https://www.convertingquarterly.com/ConvertingQuarterly/Indu... This solid sta…

You are right. The company you mention is focusing on the aviation industry. Drones and light airplanes. Weight matters a lot there. To the point where saving weight is worth a lot to manufacturers. Basically every kilo you save is more useful load and range. It's also a very conservative market. Most of the planes in the process of being certified, or already certified (like the Pipistrel trainer) are using batterie…

Manned airplanes are a conservative market, I would imagine that unmanned drones are not? Especially cheap consumer ones?

Re: Solid-State Battery Has 2x the Energy–and No Anode

#140

Earlier quoted context omitted.

Actually, energy storage by weight is not as big a deal for electric cars. Regenerative braking can recover most of a vehicles kinetic energy, which is where the weight dependent energy goes. This is why several hybrids get better fuel economy in city driving than highway, the biggest losses are due to aero which increases nonlinearly with speed. Otherwise yes, it's important to find something better without sacrific…

>Regenerative braking can recover most of a vehicles kinetic energy I used to think that was the case, but then i think i read somewhere that it only recovers 20% of the kinetic energy. Can't find it anymore though

As with anything else it depends what you optimise for and at the most basic level the car uses the engines to accelerate at all speeds but might need to use break pads at slow speeds.
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