Hey @upio9 welcome to the community 
I don’t think I know the solution, maybe you can try @Halano configuration, and let us know if is working for you as well.
I honestly never went into this, I never had this kind of problems. Just for say you my Laptop with Core I5 8000 series, almost from 2017 - 2018, it’s battery is working very great. When I work with the Laptop I use to toggle off the AC power, then, when it’s battery is low at almost 5%, I use to plug in the AC power.
This PC is equipped with Microsoft Windows (for work needings) but since when I own it I never had a problem, the battery is working like the first day … or similar. A full charge is almost 3 hours - 3 hours half working with Visual Studio code.