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.
We have a universal, standardized, cheap power cell. To this day you can use the same type of power cell in any low power device since it was standardized, going all the way back to things made in 1947. We then made it reusable for hundreds or even thousands of uses a piece, and they still only cost a few bucks.
We then replaced it with millions of different single-purpose batteries that are only compatible with one thing each.
People keep trying to gaslight me into thinking this is somehow better.
Make them illegal, and I'm not kidding.