Dewalt battery repacking
The size used in these 18v DeWalt batteries is Sub C. At 1.2V each when you put 15 of them in series you get 18v, which is what we'll be doing.
Start off by doing the bottom first. Use the diagram to lineup and make sure you have the correct polarity facing up (or down depending how you want to think about it.) I use a flux I got from the stained glass store just because I had it around. I dipped a Q-tip in the flux and polished the part of the battery I was about to solder too. With my soldering iron on 450°C (HOT HOT HOT!) I made a pool of solder on the battery where then used some tweezers to place my copper wire into. Taking the iron away the solder cools and the copper wire is secured to the battery. Do this around 30 more times and you’ll be done in no time. The diagrams below show the wiring scheme that should be followed.
A good thing about doing this yourself is you get to choose the batteries you use. The 1700mAH NiCad’s I used were on sale and ended up costing me ~$35 total. If I wanted, I could have used 4500mAH NiMH cells for extra performance. But I was just looking for the cheapest possible method to get a working drill again at the time.
I purchased my batteries from http://www.megabatteries.com
Pay attention to which side is Side A when flipping the pack to solder the top.