@Colors, I can’t say what the cause is either. But here in the forum many users complain about the increased energy consumption since /e/OS-U 2.7.
Maybe it’s the App Lounge, which often doesn’t work properly, but constantly searches for apps in vain and doesn’t install them when it finds them?
Info: MicroG using a lot of batterypower
Side note: Unihertz Atom_L runs with GSI e-2.8-a14-20250221-UNOFFICIAL-GSI-arm64_vN.img.xz: signed keys 
by @Colors