battery life during photo import

During photo imports directly from my camera to my 30 GB iPod Photo, the battery is consumed after 30 - 45 minutes of transfer time. I am going to China and will be taking lots of pictures each day. What should I do if the battery dies in the middle of an import each night? If I recharge the iPod and start the import again, will the iPod start importing from the beginning of the camera card again (and die again before it finishes)? Is there a way to only import photos that have not already been imported? Or will I be in a loop whereby the next iPod import will start back at the beginnng and die again? Is my battery life typical, or is my battery bad? Are there any ways to deal with long downloads using up all of the battery? Thanks for your thoughts.