I know what you want, but its not possible, because the ipod can only be charged by the host while its plugged in, even if there is power connected unless the host (CLAS is the host) sends a signal to say its going to charge, the ipod wont accept it, it will accept it for a split second before it realizes and then even though there is power there it will stop charging. there is talk of matt changing the firmware to allow this, but when or if it will happen is unknown.
google is your friend for larger battery mods, but since the charge control program is internal and its a lipoly battery it could be a little risky. as long as its still exactly the same voltage youde probably be ok
Edited by qusp - 10/8/11 at 4:31pm