Very few people have ever had good experiences with generic batteries. Either they don't work at all, or work for a short time.

My advice is to make do with one battery until you can afford a real Nikon battery.

If you start out shooting with a full charge, you can normally get several hundred photos out of the original battery. They are very good. One of the main power sucks is the display--go into the menu settings and set it for the shortest automatic off time, and minimize your use of it while shooting.

working on it in Middle TN
Nikon D3100
18-55 mm Nikkor VR
55-200 mm Nikkor VR
55-300 mm Nikkor VR
150-500 mm Sigma OS

Visit my Nikonians gallery.