A new snap-on battery that can extend the talk time and power on an iPhone 3G, 3GS or iPod Touch 2G device by around three hours (up to 100 hours standby) has been released by Ethereal Home Theater. No bulky or clumsy cords, and designed to look like an extension to a 3G iPhone, this is one of the better-looking spare batteries going around.

A unique feature of this device is the iXpand 3G’s exclusive TuneLink technology that allows users to enjoy full use of iTunes while the iXpand battery is still attached. The unit recharges using an iPhone 3G AC adapter or USB cable and includes an LED indicator that shows charging status.

The unit is small enough to carry in a pocket or purse and rapidly recharges the internal battery of the Apple device it’s attached to.

The Lithium Polymer 500mA battery took 14 months to develop in conjunction with Apple. It weighs a mere 1.4oz (40g) and measures 6.1 (w) x 3.8 (h) x 1.16cm (t).

We tried out the device (supplied by Sound&Image;) and while it didn’t fully charge the near-flat iPhone, it gave us plenty more talk time. This is in line with the instructions on the pack which say it doesn’t hold as much charge as an iPhone battery but would deliver up to three hours of additional talk.

And, like it promised, it quickly charged the iPhone and we were able to disconnect it shortly after.

To fully charge the iXpand takes around eight hours first up but only about three hours every subsequent recharge.

The iXpand sells for US$69.99 and is available online and through local distributors.

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