"It'll be about the same as the original PSP," Sony's head of its Worldwide Studios Shuhei Yoshida said. Battery life can vary based on how a product is used. According to Sony's knowledge center page, the current model PSP systems average between 3 to 6 hours during gameplay and 3 to 5 hours during video playback.
Factoring in 3G, Bluetooth, and Wi-Fi connectivity, the average life of the battery drops. Of course, UMD playback demanded more juice due to the system's spinning parts, so the NGP's proprietary, card-based media solution [via GameInformer] could help keep it within the 3 to 5 hour range.
Sony Europe boss Andrew House told Eurogamer that the NGP will have a "good, solid battery life because of two factors." The aforementioned proprietary, card-based media and the system's OLED screen [via Joystiq]. However, it's unclear how much juice the system will require as it maintains a connection to perform special tasks as gamers are not playing the latest titles.
Like the Nintendo 3DS' "Street Pass" feature, the NGP will automatically connect and share information between systems as well as provide users info on gaming habits in the area in a feature entitled "Near."