A surprising breakthrough could help sodium-ion batteries rival lithium—and even turn seawater into drinking water. Scientists discovered that keeping water inside a key battery material, instead of removing it as traditionally done, dramatically boosts performance. The “wet” version stores nearly twice as much charge, charges faster, and remains stable for hundreds of cycles, placing it among the top-performing sodium battery materials ever reported.
  • apftwb@lemmy.worldEnglish
    15·
    5 hours ago

    the strategy of retaining crystal interlayer water yielded a specific capacity of 280 mA h g−1 at 10 mA g−1, one of the highest capacities reported for SIB cathodes in literature.

    All I could find. This isn’t a statement about capacity(?) Units are wrong(?)

    Its worth noting how preliminary this research is. Currently these “batteries” are just jars with chemicals.

    https://pubs.rsc.org/en/Content/ArticleLanding/2025/TA/D5TA05128B

    https://www.rsc.org/suppdata/d5/ta/d5ta05128b/d5ta05128b2.mp4

    • finalarbiter@lemmy.dbzer0.comEnglish
      5·
      3 hours ago

      mAh/g (milliamp-hours per gram) is essentially still a measurement of capacity, but in terms of current instead of power.

      We can do a little dimensional analysis here to translate between them. Power = Current x Voltage, so you’d multiply this (Current x Time)/(Weight) value by the nominal voltage of the cell to get to (Power x Time)/(Weight).

      Phone batteries are often specified in units of Current*Time (e.g. milliamp-hours), but I’m not completely sure why. I think it has to do with voltages being standardized for certain types of cells, so the only real variable in the battery capacity is the current.

      Edit: rearranged some ideas to make more sense

      • Wispy2891@lemmy.worldEnglish
        4·
        2 hours ago

        I’m not completely sure why

        I think it’s marketing

        5000 mAh is much a bigger number than 19 Wh and marketing loves huge numbers

        Kinda like BMW did with the i3.

        In 2013 Tesla was selling a model with a 60 kWh battery so BMW had the genius idea to install a 20 kWh battery BUT refer to it as “60 Ah” battery.

        Tesla introduced the 90 kWh battery? BMW responds with a 94 Ah battery (28 kWh)

        Newest Tesla has 100 kWh battery now? BMW has 120 Ah battery (38 kWh)

        “See? Higher number!”, says the marketing

        And in order to have a comparable range number they had to implement heavy weight reduction techniques like using carbon fiber for the body, negating any cost saving from the smaller battery AND giving the owner a total loss after small collisions as it shatters instead of bending