How moisture resistant is the GoPro's secondary battery?

Question

Batteries

There is additional acc to GoPro 4 ABPAK-401.
The task is that you need access to the Mini USB port on the battery itself (connecting an external microphone) and of course a problem arises - you can’t use a sealed box, only an elongated box with an open "back" and "sides" (I don't know what it's called correctly)
I looked carefully - the boxing gum tightly separates the camera and the joint from the battery at the edges => water will not get to the camera. But what will happen to the battery if, for example, it will be in the rain. The weak point (in my opinion) is the LCD with the indicator and the port itself. The rest seems to be well made and without holes. Interested in experience - who brought to what extremes?

Answer 1

I determined it by the method of poke. Not moisture resistant. The rain did not survive, although I notably isolated all the holes