Ultra 3 Battery Life = Only 24 hours?

[Frankfurt]

I’m shocked how much better battery life I get out of Ultra 3 vs 1. On a non workout day I would be down to about 50% after 24h including sleep tracking. My Ultra 1 still was at 92% capacity after 2 years. The U3 ends that same period at 80%. I’m sure I can go 3 days without charging and that in regular power mode.

 

[jonh229]

On the Watch go to Settings > Battery > Battery Health and you'll see Optimized Charging Limit.

It's a bit confusing. It does not say it limits to 80% but in rereading I suppose it implies that. On my phone there is an actual limit so that is why I asked. I've had Optimized set since I got the watch but it goes past 80% if I let it. For my convenience I charge it at the same time each day unless it happens to have a significant remaining charge. In the week that I've had my U3 the battery is typically around 35% when I charge and takes ~30-35min to get to 80%.

 

[BugeyeSTI]

yes, but there is no option to set it to a specific number. And people seem to think that there was one.
I honestly can't remember, I do know that it turned that feature off when it was new in iOS 18 (17?). Maybe only on the phone you can set a specific number?

There never has been a setting on Watch OS like that. The only setting ever offered was optimized battery charging which tries to learn your charging schedule then only charges to 80% then pauses, then charges to the full 100% before your need it. iPhone used this method too but it never worked properly, at least in my experience using it, I always disabled it and setup shortcuts and used a smart outlet to start charging at 40% and shut off at 80%. My 15PM has the adjustable charging limit which I set to 85% and it works well. Although it will charge randomly to 100% supposedly to calibrate the battery from time to time.

 

[Toonartist]

Something definitely sounds off if you're only getting 24hrs with an Ultra 3. I've been very surprised with WatchOS 26 with my Ultra 1. With WatchOS18 after a full charge before going to bed, I'd wake with 86-88% left 7am in the morning. With WatchOS 26 I'm routinely left with 93%. I've had my watch since they first released the Ultra 1 and with the previous OS I could just squeak 2 days but it would be close. Now with the latest OS I still have 24% after 2 full days. Not bad for a 3 year old watch.

As it stands, I'd be reluctant to update it again. I have all features turned on, auto start exercise routine detection etc.

 

[tom2517]

There is no proof for that.

Actually there are proof of not charging to 100% every time will prolong battery lifespan. And hence Tesla explicitly says charging to 80% instead of 100% all the time to preserve battery health, Apple, Samsung, Google and etc rolled out optimized charging limit for their phones.

Nonetheless I don’t care for the feature especially on AW with its tiny battery, so I turn it off for AW (but do use it on my iPhone).