AC battery charging

Hi folks!
I purchased the AC200p for emergency backup, but it turns out it works so well out in the toolshed, instead of that looong extension cord from the house! No flipped breakers, more startup power for my big circular saw…
So my problem is, I thought I had confirmed that the AC “on” setting eventually turns itself off, for whatever reason. If no load is present for a certain time?
I’ve been charging batteries for my cordless tools and ever since I added the one new charger, the AC stays on full time.
Since then (a couple days ago) the skies have been cloudy and the display shows the charge hasn’t gotten above 15%.
A full day of work with power tools recently never dipped it below 95%.
Maybe chargers are all different, but even so, a nearly-full rechargeable battery shouldn’t draw down the whole system overnight?

If you leave the unit on it will drain power if none is replenished daily. Same thing as idling your truck in the driveway and the next time you come out the gas tank is empty. A full day of running power tools seems optimistic and only dropping 5% of the capacity unlikely unless you didn’t run the tools. The AC power outlets will turn off without use after several hours if you turn the Eco mode on.

It was sunny when I had the big work day. So I know that works great. I guess the main question is: if chargers for cordless tools are ever satiated. Or do they trickle charge forever.
I’m sure I was keeping a fuller charge on my AC200p even when leaving chargers on overnight. But no longer. Idk, too many variables.