The cables are/work the same, but the iPhone cable has a smaller front, and also removed the clips you needed to press in to remove the cord (you can just yank it out without worrying about it)
But yeah, whenever i've stayed at a friends house or my gf's house, i've either a) used their iPod charger that they already have or b) don't charge it, because usually it'll last more than a day (unless i'm watching tons of movies or something)
I don't think the problem is with the cord.