Decision KfW55 vs. KfW40 plus

No, with KfW it’s only 50 or 60 now, which is noticeably less compared to 70.

Do you have a source for that? I’ve never heard that before. I have KfW40 without Plus, so only photovoltaic without storage. Mine is normally set softly at 70%.

Found it, it is stated in the conditions of the KfW. And it is limited to 60% for KfW40+. If you take another subsidy for the battery storage, it is even only 50%.

Should not be a problem with good battery management. That the battery is primarily charged when you go above 60%.

How this is exactly implemented in terms of control technology and whether there are already good solutions for it, I do not know now, but I can imagine it.

On sunny days, depending on the size of the system, 40-60kw come from the roof. You can neither use nor store that meaningfully. Therefore, [Speicherförderungen] should always be viewed critically. 60% may still be acceptable, but at 50% the fun really ends.

Shouldn't be a problem with good battery management. That the battery is primarily charged when you go over 60%.

As already wrote, that's completely irrelevant.
We also had a storage subsidy program. It would have been 3000€ for a 10 kWh battery, but capped at, I think, 60% (supply temperature was also 50). I then calculated the losses with a somewhat more complex Excel sheet and it was almost exactly the 3000€...