With the 49mm case size and updated design of the Apple Watch Ultra, Apple was able to fit in a much larger battery. As a result, the Apple Watch Ultra is able to last for up to 36 hours on a single charge with normal use, and even longer with a new Low Power Mode and battery optimization options.
Apple defines "normal" use for the 36 hour metric as 180 time checks, 180 notifications, 90 minutes of app use, and a 60-minute workout with music playback from Apple Watch Ultra via Bluetooth over the course of 36 hours. It also includes a total of eight hours of LTE connection and 28 hours of connection to iPhone over Bluetooth.
Actual battery life will vary significantly depending on what the Apple Watch is used for. Workouts that exceed 60 minutes will drain battery quicker, as will being on a cellular connection for a longer period of time.
Apple plans to introduce a Low Power Mode in watchOS 9 that will work on all Apple Watch models that include the Series 4 and later. With Low Power Mode, the watch will disable or limit features that include the always-on display, autostarting workouts, and heart health notifications.
The Apple Watch Ultra also has specific battery optimization functionality that needs to be set up to get the maximum battery life, and this option is set to launch later in the year.
When battery optimization launches, the Apple Watch Ultra will last for an impressive 60 hours, and it will be the first Apple Watch to offer more than 24 hours of battery life to let people go multiple days without charging. Apple says that multi-day "adventure" battery life is based on Low Power Mode and with workout settings enabled for fewer heart rate and GPS readings (which may be what battery optimization does). Apple used the following to test:
- 15 hours of workout
- 600+ time checks
- 35 minutes of app use
- 3 minutes of talk time
- 15 hours sleep tracking
- 5 hours connected to iPhone via Bluetooth
Standard Series 8 models and the Apple Watch SE continue to offer "all-day" 18-hour battery life, which can be extended to 36 hours with Low Power Mode.
Low Power Mode is set to launch with watchOS 9 on September 12, while battery optimization does not have a specific launch date as of yet. The Apple Watch Ultra is available for preorder today, and it is set to be released on September 23.
