Mophie has announced the Juice Pack 3G, which is an updated version of its battery extender for the iPhone. This Juice Pack 3G extend the iPhone 3G for an additional 350 hours on standby, while additional 6 hours of talk time and internet, eight hours for video playback, and 28 hours of audio.

The Juice Pack 3G is sold at $100 and will become available in market in September.

Ross Howe, Sales and Product Development Director for mStation/mophie, emphasizes the need of boosted battery by the power user of iPhone 3G. Juice Pack 3G provides superior battery enhancement, and keep the unique style and feel of iPhone intact at the same time.

The Juice Pack 3G ensures the protection from short circuits, over-charging, and excess heat, with smart power management that drains charge from the pack before resorting to the iPhone’s internal battery. How much power remains in the unit is indicated by 4 LED light. It also comes with a USB pass-through that allows users to charge both the Juice Pack 3G and the iPhone simultaneously, as well as synchronizing content.