I’ve been hearing about these for a few years now. Huge if they work out at a large scale.

  • lime!@feddit.nu
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    14 hours ago

    idk about that, the regularly cited reason Na-ion batteries are mainly being looked at for grid storage rather than vehicle applications is their bad Wh/l and W/kg numbers compared to Li-ion. the table in the Na-ion article seems to use “1000W/kg” without a source, and it shows lithium as being about a third of that even though the Li-ion article quotes figures up to 10kW/kg.

    seems the editors of the two articles aren’t cross-checking eachother.

    • Anivia@feddit.org
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      6 hours ago

      ion. the table in the Na-ion article seems to use “1000W/kg” without a source, and it shows lithium as being about a third of that even though the Li-ion article quotes figures up to 10kW/kg.

      seems the editors of the two articles aren’t cross-checking eachother.

      No, it seems like you have zero idea what you are talking about and are confusing W/kg with Wh/kg, which are very different metrics

    • nyan@lemmy.cafe
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      12 hours ago

      The “1000W/kg” figure appears to be from Wikipedia, which claims https://www.idtechex.com/en/research-article/sodium-ion-batteries-will-diversify-the-energy-storage-industry/30405 as a source. Wikipedia has the information in a table flagged as “Needs update”.

      Anyway, most of the lithium-ion chemistry variations drop off relatively fast in capacity over repeated charge cycles (the exception being LiFePo4). If the sodium-ion chemistry is better that way, and drops off less in the cold, it’s still worth exploring for vehicle use even if the energy density is a little lower.

      • lime!@feddit.nu
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        7 hours ago

        from other comments it seems the energy density of batteries currently on the market is about 2/3rds that of lithium cells.

        there’s also the asymmetry to worry about: with a max discharge rate of 8C but a charge rate of 3C there could potentially be limits on regen braking. if i’m understanding it correctly, sodium cells degrade quickly at higher charge rates.

    • Blue_Morpho@lemmy.world
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      14 hours ago

      Googling says 175 whr/kg for catls sodium car battery that’s already in production cars vs 270 whr/kg for Tesla’s lithium.