Här är det svaret från deras support jag talade om:

No users have to worry! What matters now is that nobody has the idea to take out the battery !

The board with the battery is with the Main Board "married" and it is used for Clone protection. In the future there will be a solution, to change the battery! That means if necessary in 5-7 years!
PS: The life of a backup battery is of course depending on the current consumption but that is in the case lower, as in a remote or a motherboard! Thus, the life is much more longer !