Need help on replacing a battery

[gamerz300]

My old MP4's battery has been long gone for a while, which made me buy my new one.

However today i decided to try to find a way of replacing the battery with what i have lying around the house. Now going based on this post any mAh which i already knew along with the same volts...

So i found a PSP battery (not knowing if it was charged or not and stupid enough to not check before proceeding but im sure there was some charge enough to make the screen flicker black like it normally does during boot up) which was 3.6V (PSP-S360 battery not the stand), so i ripped it open removed the board (maybe i went wrong here but it has 3 prongs) and tried to boot the device. Complete failure...

Now if i need that board to possibly boot the player let me know ill try but its too dark to do so for the day.

Also any other ideas? in the topic mentioned above they linked to a DS lite battery which is 3.7V would that really work?

here is the a picture:
http://img217.imageshack.us/img217/138/img1516d.jpg (2.6mb) sorry for how it looks i had didnt have a steady hand today... Also the thing on the player was part of the battery in the yellow wrapping.

Thanks in advance

Oh im also able to get to a place called Pacific Mall within 2 hours which usually sells stuff at discounted prices.

Edit: Oh also would a ipod battery work? Like a nano one or something long those lines which are also 3.7 i think.

[zack247]

ipod batteries could work, the thinner the better. try to get one built for maybe a nano, since they are the thinnest one. it looks like a ds battery way be too thick for your device, but for mp3/4/5's you definitely want 3.7v. go as high as you can with mah's, because the more the merrier, the more mah's, the longer it will stay charged. you should brobably try a thin one from something like a ipod or the sort, you will probably want something that is at least 800mah for this player.