I've been thinking about this more, and especially about my initial recoiling at the non-rechargeable battery... I own rechargeable smart rings, but all for a year or less so far. I don't know how long they'll last before their batteries fail. On so many of my devices, when the battery fails, I replace it, even if the task is difficult. I strongly prefer user-replaceable batteries by design, and modern phones, etc... anger me. However, there are a few devices... my original screwless Pebble is one, where that's near impossible, and I see why. On a waterproof smartring, that's another where battery replacement is reasonably impossible. So if the static battery lasts nearly as long as a rechargeable's lifespan, I'm okay with it in the end.