Xmultiple have come up with a battery: X-Power1 USB Rechargeable Battery Backup Cable, this is an iPhone and iPod sync cable with a twist.
With a small lithium ion battery located in the cable’s belly, the X-Power 1 can be used to recharge an iPod or iPhone even when it isn’t plugged into a USB slot.
There are four available models of X-Power1, but the latest model wont be available till August 25.
Read more on the link below.
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