Hacking DSL Battery Problem

[Lyzard]

I know standard playable time is 10-15 hours. But there is a problem with my battery. It's not too old, but unfortunately i can only play 5-6 hours

I have Acekard2 . I'm playing with lowest brightness. And if i play 3d games, sometimes batter is dieing in 4-5 hours. What should be a problem? And is there anywhere can i get original battery? or quality battery?

Thx, regards.