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

  • Natanael@infosec.pub
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    7 days ago

    1 C is defined relative to 1 hour for full discharge and 3 C means a 3x faster discharge rate (full capacity can safely be discharged in 1/3 hour, or you can discharge 3 cells sequentially in an hour). Good lithium cells tend to be above 5C, can reach 10C for peak load or if cooled.

    For a large enough battery it doesn’t really matter, but for dense portable ones a lower C rating means you have to discharge from more cells simultaneously to maintain a given output. That makes it more complicated, and you have less headroom to the battery’s maximum Watt output if you need to accelerate a car hard suddenly.

    • captainlezbian@lemmy.world
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      6 days ago

      And here I was confused why coulombs were being used as a charging rate…

      We need to abandon the “use a letter for this unit/property” crap and accept that the alchemists and accountants had it right.

    • Pelicanen@fedia.io
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      7 days ago

      NMC cells typically operate around 1-2C and LFP cells 1-3C. If you want to achieve 10C then you’re probably gonna have to look at LTO cells. All of these are lithium-ion chemistries but they each have different characteristics.

      • Natanael@infosec.pub
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        6 days ago

        (for context most my knowledge of these cells are from single cell +5000 lumen flashlights :)

        • ryannathans@aussie.zone
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          7 days ago

          Sodium ion batteries are asymmetrical, pushing charge current hard can drive the anode negative enough to deposit metallic sodium causing formation of dendrites which destroys the battery. Discharge is not limited by the same mechanism