Yesterday I fully charged both of my Nikon EN-EL3e batteries and this morning I was using it fine, and I just got home and both of them are completely drain? What could be the problem. One of them is only a few months old. It was both in my D200 with the MB-200 grip. I left it on "ON" but I always did and this never happened before. I have a third party charger that was given to me when I bought my D200 from Adorama. It worked fine before.