cross-posted from: https://lemmy.ca/post/41765246

Well this is interesting. Stick-a-node to any smartphone with magnetic back. I could see myself trying this.

  • shortwavesurfer@lemmy.zip
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    1 day ago

    By chance, do the numbers seem a bit off to anybody else? From what I understand, the battery capacity is 5,000 or 10,000 mAh, but yet it’s only being rated for 3,500 and 6,500 mAh. I heard the bottom 5% is being reserved for the mesh node itself, but that should mean the rating should be for 4,750 and 9,500 mAh.

    • MangoPenguin@lemmy.blahaj.zone
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      1 day ago

      I think they just messed up the units, 6.5Ah * 5V = 32.5Wh which seems reasonable from the 38.7Wh battery, as that’s a total of 84% efficiency which is pretty typical for a power bank.

      So it should say rated capacity = 32.5Wh.

      • Avid Amoeba@lemmy.caOP
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        1 day ago

        Most battery banks advertise their raw cell Ah/mAh ratings, which of course isn’t the effective Ah at 5V. It seems like Heltec tried listing both ratings here.

      • shortwavesurfer@lemmy.zip
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        1 day ago

        Well, your phone needs at least 5 volts. So it sounds to me as though if you’re using the node, then it can take advantage of the entire battery. But if you’re using it to charge your phone, you can only take advantage of like 70% of the battery.