After catching a glimpse of the Wii U's potential at Nintendo’s conference, some of the excitement is tempered by the raw facts on battery life. According to official figures from Nintendo, the Wii U Gamepad will only last for 3-5 hours on battery charge. Since most of its functionality shown at E3 involves players moving it in multiple directions and around the room, it may be tough to charge and play with the controller at the same time.
Potentially making matters worse, Nintendo has commented that various factors such as screen brightness could drop the battery life further. At this time it's not clear if concurrently charging the GamePad while playing will be possible, nor how long such a cable to do so will be.
Update: a NOA tweet has confirmed the GamePad can charge while you play.
Considering the controller functions, this really isn't a surprise. It's about the same as the 3DS. My hope is that Nintendo makes this a moot point by packaging it with a suitably long power/sync chord. Anything under six feet is unacceptable. Ten feet would be preferable.
I'm hoping they use a standard charging cable, like micro-USB. That way we can just buy extenders as necessary and make it a really moot point.
I think the concept of needing to connect a controller to a system via a cable during gameplay is kind of ridiculous in 2012.
Of course, this is the first step to the multi-touch, longer battery life redesign of the gamepad that comes out in a year or two.
Hmmm I think the biggest energy sucker on the gamepad is the wireless video receiver on it. According to the hardware specs the battery weighs 500g (1.1lb). That's a big battery. LCD brightness, accelerometers, gyro, touchscreen functions, and button/sticks usage are the least energy suckers. The camera however should be second to the wireless video receiver in regards to energy consumption. At least that's what I think.