Surfans F20 / Opening unit and upgrading/replacing battery?

[OutofStep]

I have the Surfans F20 and knock on wood, it's still working ok, but was taking a look at it and am trying to figure out on how to open it with the intention as to replacing the battery as well as to see if anyone here knows if there is a larger capacity battery that will work with the unit (for longer play time) than the default 1500mah one?

Can anyone let me know or point me to disassembly links?  I've tried googling but haven't turned anything up and don't see anything here.

[vitt13]

Can anyone let me know or point me to disassembly links?

Here is the video https://www.youtube.com/watch?v=k9pza1XTIU0