Having had a battery problem and being helped by Garmin support (thank you!) - they suggested deleting my activity history + soft reset, I decided to conduct a relatively non-scientific test of the watch battery life, using it what for me is 'normal'. The watch was worn continuously for the two weeks.
In summary, from 100% (24d showing) the battery ran down to 4% (1d showing) over 14 days with no recharge (some minimal sunlight - it was January!). The usage settings were continuous HR, Pulse Ox test 4 times and 8.5 hours of GPS time in total. Sync a couple of times a day. The battery life declined by an average or 1-2% overnight (presumably sleep tracking accounting for most of this). The most being 4%, but often only 1%.
My impressions: with some tweaks and more sunlight exposure I would be able to extend the battery life quite a bit, especially if I didn't use the GPS tracking (I can use my Inreach mini for extended trips). Compared to my old non-solar instinct this is a massive improvement. Glad to upgraded!
Hope this help other 'calibrate' the battery life they are seeing on their watches.
Have fun on your adventures!
