Portable Dvd Replacement Battery What Is A Good/cheap Battery Replacement For A Portable Dvd Player Audiovox D2010?

What is a good/cheap battery replacement for a portable dvd player audiovox d2010? - portable dvd replacement battery

This is because the original battery does not last longer, I think it's because they stayed in the car during the heat and plan a family vacation and I want to keep kids busy for some time ..