Please read this great blog post about EMUI and battery optimisations from MoDaco:
Below are only two important parts from this blog post, so if it does not work read the full blog post.
To access the Doze settings on EMUI 8/8.1:
- Open the 'Settings' app
- Select 'Apps and Notifications'
- Select 'Apps'
- Press the 'Settings' cog at the bottom of the screen
- Select 'Special Access'
- Select 'Ignore Battery Optimisation'
The default view in this screen is 'Allowed'. These are the apps that are exclude from Doze mode. To exclude another app, you need to change the drop down at the top of the screen to 'All Apps', pick the app for which you'd like to change the configuration and then select the appropriate option as shown below. It's probably a good idea not to just change this en-masse because, of course, it will impact your battery life.
To access the EMUI battery settings on EMUI 8/8.1:
- Open the 'Phone Manager app
- Press the battery icon
- Press 'App Launch'
You'll notice that 'Manage all automatically' is set by default. This is great, but I think I am better at knowing which apps I want to have battery draining permissions than the phone. Toggle the setting off, then select 'Manage batch manually'. You'll then see a list of all your apps, with particularly power hungry ones at the top, each with the option to prevent auto launch, secondary launch (being launched by another app) and even background running. Powerful, useful, and a great way to perfectly tune your device.