Battery calibration for Apple Watch Series 4 and 5
Apple will calibrate the calculation of the maximum battery capacity, giving you a more accurate estimate. This will happen after installing watchOS 9, according to the release notes. This update will be released next fall and can now be tested as watchOS 9 beta. It means you can get a better estimate of how long your smartwatch will last on a ‘full’ battery charge.
The cells of lithium batteries such as in the Apple Watch show wear and tear over time, so that they can no longer be charged to full capacity. This is expressed as a percentage. At 90%, the battery can only be charged to 90% of its original capacity, which of course also shortens the operating time. It's not possible to reverse this wear and tear, but you can prevent it by adjusting your charging habits. Frequently fast charging means more drain on the battery.
Some owners of an Apple Watch Series 4 and Apple Watch Series 5 noticed that the battery percentage was no longer displayed correctly after installing the watchOS 9 beta. This update fixes it. During the update, the calibration will take place without you having to do anything manually.
Apple previously performed a similar calibration for the iPhone 11 to make the battery life estimate more accurate. This happened after updating to iOS 14.5. Under Battery > Battery health you were shown information about the recalibration. This process could take weeks, while the Apple Watch is a lot faster. The Apple Watch has never had the battery recalibrated before. The Apple Watch Series 3 will not receive a newly calculated maximum capacity, as this model will not receive the update to watchOS 9. And the Series 6 and Series 7 are still so new that you don't have to worry about battery health.
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Is the battery of your Apple Watch getting shorter and shorter? Do you have an older Apple Watch and are you dealing with an increasingly shorter battery life? With these tips we hope to be able to solve your problem for you!