Besides recycling? I'm talking about the ones for the portable power tools. We go through several of these battery packs per year and I was wondering if there is any way to use the ones that won't take a charge anymore.
Thanks

There is a hardware store in Dallas, Elliots Hardware, that will open up the cases and install newer higher capacity cells for less than 1/2 the price of a new battery. They rebuilt my Makita cells for me and I am very pleased. You might see if there is a shop in your area that rebuilds cells.

rebuild them, or have them rebuilt. They normally use sub-C flattopped cells, soldered together in series. My experience is that it's cheaper to get a specialist to do it, as they charge about what it costs me to get just the cells, or less. (You can get substantial discounts on cells if you buy them in large quantities.) and I don't have to solder them, or figure out how to non-destructively open the case. If the battery packs are more than a couple years old, they'll be better than new. NiMH battery technology continues to improve, and higher capacity cells are available.

Most DeWalt batteries have a warranty on them of some sort or another. We burn through a couple a year as well. I walk back into the DeWalt store here in town, and every one I've taken in has been replaced without cost. I have two waiting to go back right now actually.