Remote key fob battery needs replacing help

[snowwolf]

The key fob on the Gen f has been a bit reluctant to work instantly recently and now it says on the dash that the battery needs replacing, I think they are different to the normal Vxr8 keys I think, as you don't need to push any buttons on the remote to unlock the door, you just push a little button on the door handle.

Does anyone know how to change the battery, never had to do it before