Wi-Fi BacPac battery-life:

The Wi-Fi BacPac's internal Li-Ion battery lasts for 3-4 hours of continuous use.

 

Wi-Fi Remote battery-life:

The Wi-Fi Remote's internal Li-Ion battery lasts for 5-6 hours of continuous use.  The remote's battery-life indicator icon always displays on the remote LCD screen when the remote is powered on.  If the remote is paired to more than one camera, the battery-life indicator icon always displays at the bottom of the remote's LCD screen.

 

HERO2 Camera battery-life:

The HD HERO2 camera's battery-life is not affected by the Wi-Fi BacPac.  It lasts for 2-2.5 hours of continuous use.  If the Wi-Fi BacPac's battery is critically low though, the BacPac will run off of the camera's battery.  This reduces the camera's battery-life by about 25%.

 

HERO3 Camera battery-life:

The HERO3 camera has built-in Wi-Fi.  Turning on Wi-Fi reduces battery-life by about 10%.