Based on the description on their site, the controller includes a built-in battery: "8.39 Wh Li-ion battery, 35+ hours of gameplay... "
That was disappointing for me. Specially condidering the Steam Frame's controllers make use of AA batteries: "One replaceable AA battery per controller, 40hr battery life"
AA Batteries might not be as convenient to use, but being able to replace them is a great advantage. All my Xbox360 controllers still work fine, but none of my PS3' Dualshock 3s.
The official docking station could be used to recharge (rechargables) AA batteries so the functionality could remain the same.
Sounds like your use case is unique and does not match the use case of the vast majority of users. Maybe you should look for another controller that meets your very specific requirements more closely.
I already have one, but thank you for the suggestion.
OP and several others have expressed similar sentiments in this thread so I'm obviously not alone in the "vast minority".
You think you're use case isn't a tiny minority because you found some other people on a thread?
A thread specifically about the use case?
This is how the world gets dumber.