Reminds me of a certain very well known startup in beacon space. I visited them some 6 years ago, back when they were finishing their fist product - a nice-looking battery-powered Bluetooth beacon, completely encased in some kind of silicone. I asked them, well, what's the expected time until battery is completely discharged, and how do I charge it back or replace it? And the answers were, a year or three (depending on use), and you don't, because by the time the beacon dies, you'll want to get a newer, better one anyway.
One of the many reasons I never bought anything from them.