Originally Posted by mdibella
I have this and, unless they've fixed it, there is a small caveat. You really can't use rechargeable batteries with the iPod touch, because they provide (1.2 times 4) 4.8V. The Touch is very fussy about its input voltage, and 4.8 is not quite enough to make it happy. If you use Alkaline batteries, it works just fine (4.5 times 4) 6V..the battery pack takes this down to standard USB 5V before passing it onto the device.
I like using lithium AAs in mine actually, they're more expensive than alkalines but they last FOREVER...and the Touch is happy as a clam with this setup.
And for more good news, they also sell a tip that will charge your Kindle using this battery pack!
Well, according to their site....
• The ONLY product that will work with alkaline or rechargeable batteries.
Does this work with rechargeable batteries?
Solution Yes it does. Our battery charger was specifically designed to work with either alkaline or rechargeable batteries. Please note, however, that all rechargeable batteries are not created equal. In fact, in an attempt to pack more “power” in rechargeable batteries, some vendors are producing AA batteries that exceed the size specifications of the AA standard. If you are running into this type of situation, please contact us and let us know as we have recently come out with a one-off solution which we can send you which will resolve the size issue.