• dual_sport_dork@lemmy.world
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    2 months ago

    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.

      • dual_sport_dork@lemmy.world
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        2 months ago

        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.

        • UnderpantsWeevil@lemmy.world
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          2 months ago

          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.

          • dual_sport_dork@lemmy.world
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            2 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.

        • Wooki@lemmy.world
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          2 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

    • Dharma Curious@slrpnk.net
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      2 months ago

      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?

      • dual_sport_dork@lemmy.world
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        2 months ago

        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.

        • Dharma Curious@slrpnk.net
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          2 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?

    • UnderpantsWeevil@lemmy.world
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      2 months ago

      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.

    • roguetrick@lemmy.world
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      2 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.