Is there a way to use a 3.7v battery as an ipod touch external battery?

i have SEVERAL old cell phone batteries that i thought i could put to use. They are all 3.7 volts with 950 mAh. while that isn't an amazing amount of power, like i said, i have many of them. i can solder (though am not usually very neat with it) and have an extra female und of a usb cable. my plan is to make the female usb end into a case that will hold the batteries in place, then plug the ipod's sync cable into this usb port. the female end will also charge the batteries via a usb male-male cable. i already have the female end soldered onto small alligator clips to start with, using pin 4 as the ground and pin 1 as the power. i know that this rig works to charge the batteries, but i can't seem to get them to have any effect when plugged into the ipod (i haven't done extensive testing). does this seem viable? is the 3.7v just not enough to work? is there anything that i am missing? please help, as i need to extend the battery life for an upcoming trip. (tomorrow)