Doing battery readouts with a fully charged Magic Mouse 2 gives always the same values. Needed a discharged Magic Mouse 2.or a tool which moves the mouse continually, so we asked two 8 year old boys if they could develop a "mouse mover" with their Lego.
Amazingly clever these boys! They call it The Magic Mouse Discharger.
12 hours of constant run was about 5% discharge.