i have found few things !
http://www.ebay.com/itm/Rechargeable-Polymer-Li-ion-battery-3-7V-2000-mAh-for-Mp4-GPS-Tablet-PC-853465-/171835612939?hash=item2802335f0b:g:frQAAOxywh1TDpvs
looks kinda sh*t quality...i have no idea there are soooo many to chose from
also i have found this !
[guide|39737|link]
also this person says that the battery isn't problem in his case....something weird could be going on...