this post was submitted on 04 May 2024
863 points (99.2% liked)

Technology

59174 readers
2961 users here now

This is a most excellent place for technology news and articles.


Our Rules


  1. Follow the lemmy.world rules.
  2. Only tech related content.
  3. Be excellent to each another!
  4. Mod approved content bots can post up to 10 articles per day.
  5. Threads asking for personal tech support may be deleted.
  6. Politics threads may be removed.
  7. No memes allowed as posts, OK to post as comments.
  8. Only approved bots from the list below, to ask if your bot can be added please contact us.
  9. Check for duplicates before posting, duplicates may be removed

Approved Bots


founded 1 year ago
MODERATORS
you are viewing a single comment's thread
view the rest of the comments
[–] [email protected] 103 points 6 months ago (3 children)

non-flammable end use

Safe and stable chemistry

Oh neat, finally a non-explody and/or unstable battery lmao

[–] [email protected] 64 points 6 months ago (6 children)

Well, only relatively.

In order to work batteries need to have a certain amount of instability built in, on a chemical level. Them electrons have to want to jump from one material to a more reactive one; there is literally no other way. There is no such thing as a truly "safe and stable" battery chemistry. Such a battery would be inert, and not able to hold a charge. Even carbon-zinc batteries are technically flammable. I think these guys are stretching the truth a little for the layman, or possibly for the investor.

Lithium in current lithium-whatever cells is very reactive. Sodium on its own is extremely reactive, even moreso than lithium. Based on the minimal lookup I just did, this company appears to be using an aqueous electrolyte which makes sodium-ion cells a little safer (albeit at the cost of lower energy density, actually) but the notion that a lithium chemistry battery will burn but a sodium chemistry one "won't" is flat out wrong. Further, shorting a battery pack of either chemistry is not likely to result in a good day.

[–] [email protected] 16 points 6 months ago (1 children)

I believe it is still better due to raw material availability?

[–] [email protected] 20 points 6 months ago (2 children)

It is definitely that. That's kind of the point, actually. Sodium is easier to come by than lithium and does not require mining it from unstable parts of the world, nor relying on China.

[–] [email protected] 4 points 6 months ago (1 children)

nor relying on China

The appeal of China is largely in the size of the labor force. Whether this tech is more or less feasible than cobalt and lithium, businesses will still want to exploit the large volume of cheap Chinese labor in order to build them.

[–] [email protected] 1 points 6 months ago

I'm sure they'll want to, but that'll be a little better than need to, i.e. relying on them for the raw materials as well.

[–] [email protected] 1 points 6 months ago

If you consider Australia unstable, sure, maybe for humans, the animals are fine unless you’re Steve Irwin, just dont go diving with stingrays

[–] [email protected] 13 points 6 months ago (2 children)

You who are so wise in the ways of science, can you explain to me if this is safe/will be super dangerous if exposed to water? Doesn't sodium, like, blow the fuck up when it comes in contact with water?

[–] [email protected] 13 points 6 months ago

Yeah throwing a piece of sodium metal into water will cause a violent reaction. Even touching it with your finger is bad because of the moisture on your skin.

But sodium chloride (table salt) dissolves in water easily and safely, resulting in an aqueous solution including sodium ions.

[–] [email protected] 10 points 6 months ago (1 children)

Well, metallic sodium liberates hydrogen real fast on contact with water, which I guess is tantamount to the same thing.

Yes. But not to the same level as just dropping a brick of pure sodium in a bathtub. In a battery like this there is not pure lithium/sodium/whatever just sloshing around inside. The sodium is tied up being chemically bonded with whatever the anode and cathode materials are. Only a minority of the available sodium is actually free in the form of ions carrying the charge from cathode to anode.

Just as with lithium-ion chemistry batteries, it is vital that the cells remain sealed from the outside because the materials inside will indeed react with air, water, and the water in the air. Exposing the innards will cause a rapid exothermic reaction, i.e. it will get very hot and optionally go off bang.

[–] [email protected] 1 points 6 months ago

Okay, that makes a lot of sense. I was asking because I wondered how viable this would be in boats/ships, outdoor areas, off grid cabins, et cetera. Seems like it's basically the same thing, then, right? Like, proper battery maintenance and you're good?

[–] [email protected] 7 points 6 months ago (3 children)

There is no such thing as a truly "safe and stable" battery chemistry.

Is it even possible to have energy storage of any kind that is truly safe and stable? Some are better than others, of course.

[–] [email protected] 13 points 6 months ago (3 children)

Giant springs are fucking scary. Energy is dangerous when you store a lot in one place.

[–] [email protected] 11 points 6 months ago

Large flywheels are well known to be terrifying mechanical monsters, despite just being a spinning disc

[–] [email protected] 8 points 6 months ago

A couple decades ago I worked at a place that did power generation turbine controls.

One thing I worked on was a redundant sync check for connecting turbines to the grid. A turbine has to be brought up to speed, about 3600rpm in the US, before being connected to the grid. The sine wave coming out of the generator needs to match the sine wave on the grid.

If they are mismatched when the huge breaker closes, it’s not a shock or fire hazard, it’s an explosion hazard.

[–] [email protected] 2 points 6 months ago

Dams are scary too, I just hope people are able to decommission them slowly when the time comes. Otherwise the deluge is going to suck.

[–] [email protected] 3 points 6 months ago* (last edited 6 months ago) (1 children)

Is it even possible to have energy storage of any kind that is truly safe and stable? Some are better than others, of course.

considers

Kinetic energy of a body in orbit, I suppose. Like, you want to accelerate the Moon, you get a bigger orbit. We pull energy out of it via tidal generators, and in theory, we could speed its orbit up, increase its altitude.

I mean, it could theoretically smack into something, but it's not gonna hit the Earth very readily, and the speed of an object that isn't in Earth orbit, like an asteroid or something that hasn't been captured by Earth's gravitational field, is probably more of a factor in a collision than the speed of something that is.

At a smaller scale, I expect that thermal energy storage can be pretty safe, as long as you keep it within bounds. Like, if you wanted to insulate a lake and crank its temperature up or down ten degrees, probably not a lot that it could do even if the insulation was penetrated. The rate of energy release is gonna be bounded by convection.

[–] [email protected] 2 points 6 months ago

The orbital one sounds interesting. That’s a lot of energy, and it could do a lot of damage, but it seems very stable if left untouched.

My gut suspicion is that with something more safe/stable, you would also be dealing with a low quality/potency source and/or low efficiency.

[–] [email protected] 2 points 6 months ago (1 children)

On a small scale yeah. The sun heats rocks and they're able to store heat for up to an hour or so. Cats can attest to that.

Same with large bodies of water; the ocean, lakes, pools, etc.

[–] [email protected] 2 points 6 months ago

I guess in my head I was implying that it was energy humans store for other humans to use at grid scale. When I said "of any kind” I guess that’s not what I meant, lol.

So in my line of thinking, you’re right about e.g. using the sun to heat a rock. But if we use the sun to heat something for electricity generation, or we heat some medium for energy storage, I bet that will be pretty potent.

Besides, past the small scale into the smallEST scale, it’s all just energy anyway, man. 😎

[–] [email protected] 7 points 6 months ago (2 children)

If you poke a hole in it, is it just as exciting as lithium?

[–] [email protected] 19 points 6 months ago (2 children)

A different kind of excitement without flames.

Sodium cells have been out of the lab for at least 8 months now.

They're still a bit pricey but the price is quickly falling

[–] [email protected] 2 points 6 months ago* (last edited 6 months ago) (2 children)

These are more fun then lipos... I wounder if u pack a tesla full of these..will it manage to achive escape velocity after a crash? I mean gas cars and lithium batteries right now just turn car into lots fo smoke and flames..but these might really change how we see crashes...

Edit: I feel like I need to add an /s somewhere...the amout of serious replies to this comment are concerning 🤦

[–] [email protected] 7 points 6 months ago (2 children)

That explosion doesent seem much bigger than a firework thats smaller than the battery’s size. With as much as a car weighs and the amount we already do to protect batteries in electric cars i imagine the explosion from these could be easier to manage safely than a lithium fire. I also wonder how harmful the fumes are compared to lithium

[–] [email protected] 7 points 6 months ago (2 children)

Especially considering there's no fire from a sodium cell, just a quick bang. They definitely seem a lot safer.

[–] [email protected] 3 points 6 months ago (1 children)

We already know how to take care of this in big capacitors. You put a breakaway vent in.

[–] [email protected] 1 points 6 months ago

Yep, cylindrical Li-ion cells like the 18650 already do this.

[–] [email protected] 3 points 6 months ago

Yep, less/no fire is very important when creating battery banks with many cells. The probability of single cell failure spreading to adjacent cells is reduced, making a catastrophic failure of the entire bank less likely.

[–] [email protected] 1 points 6 months ago

My hopes of flying cars has been dashed 😐

[–] [email protected] 2 points 6 months ago

LiPo batteries of the same capacity actually have the potential to be much more dangerous than the sodium cell shown here.

LiPo packs typically use flat, soft walled cells which are far more susceptible to being punctured. In the event of a puncture or overcharge event, high temperature enduring flames are produced, with the severity and duration largely depending on the amount of energy within the cell. LiPo batteries also degrade at a much faster rate (both over time and with charge cycles) and have been known to spontaneously combust in storage while at rest.

With the sodium battery, the thrust produced by the puncture could have been easily been overcome by properly securing the cell.

[–] [email protected] -1 points 6 months ago

Here is an alternative Piped link(s):

A different kind of excitement without flames

Piped is a privacy-respecting open-source alternative frontend to YouTube.

I'm open-source; check me out at GitHub.

[–] [email protected] 1 points 6 months ago

It is if it's a dry electrolyte cell.

[–] [email protected] 4 points 6 months ago (1 children)

the notion that a lithium chemistry battery will burn but a sodium chemistry one “won’t” is flat out wrong

Flinging a brick of sodium into my bathtub to prove you wrong.

[–] [email protected] 5 points 6 months ago

Post vid, please.

[–] [email protected] 1 points 6 months ago* (last edited 6 months ago)

Doesn't take into account the reactivity difference with the matrix either. Solid state batteries are in a vitrified matrix essentially, and glass don't burn. Would make a lithium solid state battery likely safer than this.

[–] [email protected] 5 points 6 months ago

But I like my inextinguishable fires :(

[–] [email protected] 4 points 6 months ago (1 children)

Lead acid has been there for a hundred years, lithium phosphate is another option.

[–] [email protected] 2 points 6 months ago