Mophie’s new Juice Pack Air is heaver than Helium, but will carry you farther

Mophie announced its second iPhone 5 battery case, the Juicepack Air for iPhone 5 on Monday. Since it’s been just two weeks since its first iPhone 5(s AAPL) battery case was released, one wonders what it could have possibly improved upon. In a word: power.

The main feature Mophie improved with the Juice Pack Air is the size of the embedded lithium battery. While the Helium comes packed with a 1500 mAh batery, the Air comes with a larger 1700 mAh battery. This is the difference of being able to fully charge the iPhone 5 to 100 percent with the new Air, or bring the iPhone 5 up to an 80 percent charge with the Helium.

So what do you give up to gain so much more battery life? Size. The Juice Pack Air’s dimensions are 2.60 x 5.54 x 0.63 inches and it weighs 2.68 ounces, compared to the Helium’s dimensions which are 2.49 x 5.49 x 0.59 inches at a weight of 2.44 ounces. It does not seem like much, but every little bit matters when you are trying to wrap your hands around the longer screen of the iPhone 5.

The one feature that is still missing from both the Air and the Helium when comapred to other Mophie battery pack cases, is the ability to sync via the attached cable. The Mophie Juicepack Air for the iPhone 4/4S will allow you to both charge and sync via the cable. It’s a feature that may be important to you if you still tether your iPhone to offload photos or sync to your music library on your computer.  Mophie claims that both the Juice Pack Helium and Air cases for the iPhone 5 will only allow you to sync wirelessly when charging, hardly a feature of the case, mind you.

The Juice Pack Air will cost you $99.95 compared to the Helium’s price tag of $79.95. The other main difference that the Air has compared to the Helium is color. The black version of the Mophie Juice Pack Air is available now and will ship in seven to 10 days. If, on the other hand, you are interested in either the red or white version, you will just have to wait until March 22.