Alternative to direct connect to battery
I use a rechargable charger. I can fully recharge my iPhone somewhere in the neighborhood of 3-5 times per charge. I brought it to Bloomsburg for the 2011 rally for my charging needs. I didn't initially buy it for motorcycle riding but find it suits my motorcycle riding needs. Your mileage will vary. Note: the one I bought can NOT recharge an iPad but they do make ones that can.
I also use it during days of heavy iPhone use and for when I travel. That's why I originally bought it. I bought mine Feb 2011 and have been very happy with it.
Here's a link to what I purchased from amazon.com: [URL="http://www.amazon.com/gp/product/B0013G8PTS/ref=oh_o00_s00_i02_details"]Rechargable charger link[/URL]