Your kid wants to play wii but you are lazy enough to go and buy batteries for him in Saturday morning. Creativity often comes from lazynnes , and i had some smaller batteries bought from IKEA that could fit in wii controller. Go to your kitchen get some of aluminium. foil and wrap it 7 to 8 times (i dont think you can do more). it will be enough to make a contact between spaces of batteries. Enjoy.