A growing number of users are reporting in forums Xiaomi and Reddit about problems with battery life after the last update MIUI 12. There was a similar problem with MIUI 11, which quickly drained the battery of the Xiaomi Mi 9T and Redmi K20, and now the situation is repeated with MIUI 12.
In this same thread he also states that setting restrictions on the use of applications in the background can help improve autonomy, although it should only be a temporary solution to Battery life problem after updating to MIUI 12.
It seems that the ‘Android System’ application consumes much more after receiving the MIUI 12.0.2 update on the Xiaomi Mi 9T. The cause is not known, but this excessive consumption is such that many users have noticed a drastic drop in the daily hours that they can use the mobile. The user in charge of creating the thread on Reddit states that the application usually spends 10% and after updating it spends 25%.
More and more users confirm this bug for that version in the thread. If you are waiting to update to MIUI 12 on your Xiaomi Mi 9T, we recommend not doing it if you have received version 12.0.2.
While the owners of the Redmi Note 8 Pro, Xiaomi Mi 9, Mi 9T and POCO F1 have reported on the forums about the battery drain issue, not everyone seems to be experiencing this failure after updating to MIUI 12.
Owners of phones like the Mi 9T Pro and Mi 8 SE have even reported an improvement in battery life , so it is unclear under what circumstances this issue occurs.
A moderator from the Mi Community posted this comment in response to a POCO F1 owner who lamented the shortened lifespan of his device:
In the forums some ideas are given to improve autonomy such as doing a factory reset, making sure that all the necessary updates are installed, and even not using My Account due to its background processes.