4 ms·

And, the battery is non-replaceable. Once it dies (two years) you have to buy a whole new card. Nothing about Coin ever made any sense to me.

• JoshTriplett 11y ago
  Just as with thin laptops, replaceable batteries make it harder to remain thin. Current systems pack every bit of unused space with battery cells. There are several issues with Coin's approach, but unreplaceable batteries aren't one of them.
  • Dylan16807 11y ago
    But isn't the battery not even rechargeable? Sure, it's hard to let it be replaced in that form factor. But how about one I recharge every 6 months instead of one that lasts 2 years before dying forever.
    • JoshTriplett 11y ago
      Rechargeable batteries are larger and less efficient than the equivalent non-rechargeable battery, and you then need some circuitry and mechanism to charge them. A charger might well be more expensive than the card, significantly larger, and more intimidating for prospective users. And the card itself would then last less time on battery and would likely be thicker and heavier. On the other hand, making it rechargeable would allow for a pile of "charge card" puns.
      • Dylan16807 11y ago
        >larger and less efficient Sure, that's why I put in the 4x reduction. They're not that much worse. >circuitry and mechanism A charger circuit costs 25 cents and doesn't have to be integrated into the card. It already has a sort-of base station you use when you're programming it. All you really need is a low-current 4v source. You could make a USB charger for a tiny lithium ion battery out of a cable, a diode, and a resistor.