yeah Nimh is something like Nickel-metal hydride which is (im just guessing) one type of acid used in a cell, Lipos, Lithium Polymer batteries are the same, just require much more attention as they need a special charger and they could effectively...blow up your house if not charged correctly, and they cannot...i repeat NOT reach level 0 or they will break, they do last longer though, i dont think it is worth it?