How long does a battery last?
Inside each beacon is a non-rechargeable lithium battery that should last up to 2 years. Yes, the Bluetooth is really low energy. If the battery is running out of power, you’ll be notified. You don’t have to worry about changing it, because in two years time you’ll probably get your hands on our new much more advanced Beacons.
Seen at estimote FAQ.
So apparently now it’s cool to announce that you are expected to replace a product before its battery runs out. At least the other guys are subtler about it.