Either something is wrong with the camera or something is wrong with the batteries you are using.

I have a Moultrie that has been out for over 3 months and the battery is showing to be at 99%. It has taken well over 1,000 pictures in that time. I use the rechargeable 6V lantern battery from Moultrie and a solar panel on it. A while back I switched the solar panel to a different camera for a few weeks and it took 400 pictures and the battery dropped to 85%. Put the solar panel back on and it climbed back to 99%.