So far I only found pins which are powered up with 5V when the charger is connected. I have to figure out if there are pins also available only in battery mode. For now nothing is melted. Hope to continue without any problems.
Miix and wireless charging
While testing around to find a 5VDC source inside the Lenovo Miix i stumbled above wireless charging. So i will order a Qi-Universal receiver for charging available at amazon LINK. I am sure it will fit in the back of the Miix. The only thing which makes me thoughtful is the aluminium backcase. I hope that it will work even there is only a 500mA source then. For overnight charging i think this will be enough. Additionally i will try to solder the Qi receiver inside the Miix so the USB port will be free for mobile charging.
—Edit—
There are different sources for 3.3V around. Maybe there are USB 3G sticks available which are working with this voltage. This would be the last hurdle to take for a full mobile internet experience with a non 3G version of our Miix