I am going on an 8 hour road trip from Slidell, Louisiana to Hot Springs, Arkansas. I plan on using my iPod a lot, and I have a movie on my iPod to watch on my way there and I want to listen to music. I want the battery to last for a big majority of the time, so what can I do to make it last longer? I usually have the wifi off and the brightness down, which helps a lot, but I like my music LOUD.