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Series 4 drained in 4 hours after installing 10.1.1, still reports 83% battery capacity?
(alien.top)
Was surprised to find my watch died overnight- I usually go to bed at full and wake up with 70% remaining, but last night I charged it and installed the update, wore it to bed in Sleep focus around 5, and it was dead around 9
Battery capacity really doesn't have much to do with battery usage. Just how much the battery can hold compared to when it was new. I used to have a Series 4 with 83% capacity and it would last me 20 hours on WatchOS 10. I upgraded to a Series 9 and gave the 4 to my spouse. It might last them 12 hours but they have a lot more notifications activated on it and use it for Siri extensively.
Your usage, notifications, and background apps installed are what eat your battery. Unfortunately, the watch doesn't seem to report the apps using the most power like other devices. This means you have to use trial and error to try and reduce usage the most.