Extending laptop battery life when running mainly on AC power...

lenfirewood

Hi a few years ago there was a sudden massive change in manufacturing smartphones ie where the vast majority were supplied with detachable batteries that swiftly changed to where now it is the other way around. Sadly the same thing seems to be happening with laptops and this is in my view a more serious issue because many of us like to run our laptops MOST OF THE TIME ON AC POWER. That didn't used to be much of an issue because the batteries were easily detachable without having to unscrew panels in the laptop (which by the way invalidates warranty on most models as soon as you do that!).
So now for those of us who run our laptops mainly or even almost solely on AC power and having non detachable batteries this becomes a serious issue unless you are happy to shell out for having new batteries installed every 9 months or so!
My question is therefore not so much how to extend battery life whilst running on battery only but rather how to extend the overall life of my battery by reducing charge cycling to the absolute minimum whilst running the laptop on AC power only?
My new laptop by the way for which I am seeking helpful advice is an ASUS Vivobook X51OUF with 4GB ram and comes with Windows 10 pre-installed but I also intend to dual boot it with Linux Mint.
[this is the same question I posed in another forum but so far not received a substantial response]