Help!!! Trying to replace torched battery due to water contamination---IPOD works fine with adapter-not at all with battery. Here is question--batteries available on websites and amazon for this model say 850Ah/3.7v...Back of IPOD says 5.30v-1a max. How to tell the correct size for the 160g. Is it best to pull the battery first for exact match, or is there a way to go by serial # for exact match? ps-haven't opened IPOD yet or ever...Know it will be a bear after watching numerous repair videos but think it will be worth it. Thanks Don