I found a video review of the Phonak Paradise rechargeable. The review itself is not very interesting. But if you are quick with clicking the video Play/Pause buttons then you can capture some still-images when they show fast moving parts illustrations.
It appears that the battery is encased inside that black container with a cover that screws on. I doubt that it has a wire soldered directly to the battery. At least now we have clues as to what it looks like.
Remaining questions;
- Where to find a replacement Battery?
- What happens to the IP rating for moisture control if we open the case?