That's right, I expressed myself unclear.
What I mean is the small built-in battery (or capacitator ). This you only can see if you unmont the front of the camera with the 4 blank screws.
The built in battery (capasitator) has two different sizes on my cameras, one smaller at the first camera i bought (january 2016) and a larger at the second camera (mars 2016).
This small built in batterys function (I believe) is to keep the date, so it does not change when replacing the larger rechargeable battery. (?)
I have had no problem with the main batteries. They are good.
I have 10 of them, two orginal, some Sj cam and some another brand and together with a powerbank I never had run out of power yet!
Here is what happened first time I tried to open up the camera:
(Since I made the video, I have managed to open the camera).
This strange metal objects was on the first camera (in the holes for the screws in the front).
I not put them back, result that two of the screws are not festing properly...
On the second camera I not had this metalpieces.
So after opening it I have been able to focus the lense correctly.
After that the quality on the video / phots is fantastic, I could almost not believe how good it was, even on my big screen.
So good that I almost can accept to have the date set as january 2015...
But it would nice if it was possible to solve - of course.