Hello. I have a 10" coby portable dvd player. Its oem battery is 3500 mAH 7.4v li-on. It lasts about 1 movie. Can I make longer life battery pack with rechargeable AA, each 2000 mAH, 1.2v? To have the player function, which do I need, mAH or volt? That is, do I connect the batteries in series or parallel? Is either option even workable for a player that came with above spec battery? Thank you in advance.