So I purchased the Power Cover yesterday. I did all the updates and let the Surface and cover charge all night last night. Now I have it here at work and it's working fine. Just wondering which battery drains first? I see in the indicator, Battery 1 and Battery 2. I assume Battery 1 is the Surface's battery. So do the batteries together works as one big battery or does one drain first and then the next? I did some searches here, but really didn't find the answer or maybe I wasn't using the right keywords to get the answer I'm looking for. Thanks all.