Ive been using the same set of rechargables for a little over 2 years. I would guess I get 8-10 hours detecting on a full charge,have about 20 bucks in them. After reading up about them I learned to never drain them totally dry,try and store them in a warm place and try to keep them charged even if they arent going to be used for awhile. I detect alot and cannot imagine how many batteries I would have bought and thrown away,it always kills me to see people talk about spending the money they found on batteries. If you do feel you have to keep buying batteries and throwing them away please at least keep a shoebox you can throw them in and take to a recycling spot,you will be shocked when you see them start to pile up,HH...Shoot