Replacing a Ni-Mh battery to AC input??? Hello, I have a cordless drill which use a 14.4v Mi-MH batter source. The battery does not work anymore. It will costs me $150. Here is my question. Is it possible to replace the power source from the battery to AC adaptor. I mean as a DIY. I have done many DIYs but not with electricity since I am in Electrical Engineering problem. The school teach me a lot of knowledge which I don't know when I can actually apply to. I would like to have this one as the first project. Please help me what I need... Thanks.