These do have user replaceable batteries. It doesn’t appear so but a guitar pick type but if plastic inserted between switch and the case of the remote section will take the switch front off. There is then a small screw to remove and you can get to the CR2032 battery at the back.
Useful to know as I got sent one with a dead battery but could replace rather than return the unit. I’m using these more and more now and they seem a lot more solid and reliable than the Hue wireless switch so good to know they have life beyond one battery.