Thank you for using Xiaomi products. As the battery level drops, the device's power management system adjusts to preserve the remaining battery life. This can lead to increased power consumption, especially if the phone continues to perform resource-intensive tasks or if background activities are still running. It is recommended to enable battery saver or ultra battery saver mode when the battery is low.
Note:
The path to enable battery saver or ultra battery saver mode: Go to [Settings] >> [Battery] >> switch [Current mode] to [Battery saver] or [Ultra battery saver].