255% available (plugged in)

I tried to update and reinstall driver, it says i have the best drivers installed on my device.

It's a bug.. i have it since 1803 or even earlier. This is not related to old drivers at all. You shouldn't need to install any driver for windows to be able to tell you the right value.

There are lots of people affected by this, and it affects all brands.

I have the same problem in my ASUS GL553VD laptop. 255% available is shown when you scroll over the battery icon. Sometimes the battery is detected sometimes its not. Also, the battery indicator constantly keeps on blinking like the laptop is about to run out of battery. I have already purchased two replacement batteries which did not solve this problem. Even tried replacing the charger but the issue remains.  

One thing that I have noticed is that when you unplug the AC adaptor, the laptop turns off immediately. But when you disable or uninstall Microsoft ACPI-Compliant Control Method Battery from device manager the laptop does not turn off. In fact it lasts until the battery is drained out completely. I have no idea whether it is a hardware issue or software issue.

It actually does matter in my case. Whenever I have the battery not inserted and the 255% is shown, my computer is capped at 34% of CPU performance. I guess it is due to the "charge" being outside the possible 0-100. When I insert the battery (regardless of charge cable plugged in or not) all is back to normal. This is really annoying and has worked fine prior to the November 2019 Windows 10 Update. However, I can't roll back the update since more than 10days passed until I figured this out.

Hi ChaiLeonido, I am Dexter, an Independent Advisor, here to help you.

Do you mean the "Scale and layout" from display settings is set to 255%?

Could you please attach a screenshot of this issue?