I have exactly the same (5ah) batteries. For a "normal" cut, the mower runs for approx. 20-30 min. My lawn is approx. 140 m2 and after 10-15 min the batteries still show approx. 50%.
I find the mower with the batteries very good and handy, even in its 3rd year of operation.

The Accus fit. The question about the area is difficult to answer because the height of the grass and the desired cutting height are decisive. In my experience, you can easily manage 100 square metres with tall grass and a cutting height of 5. I am very satisfied with this mower.