So, your power drill battery dies. What now? Fork over 85 bucks for a new one? I don't think so. After searching high and low on the internet for a good price for a replacment battery I found the retail for my Black & Decker 14.4V to range from 35-85 dollars. Riiiight. Time to make your own!
At this point it would be good to mention you should really discharge the pack before you continue. Don't play with electricity unless you know what you are doing!
Step 1: Let's find out what is inside!
I had a little brainstorm and decided to open this thing up and see what makes it tick. It's funny, I always thought there would be some mystical magical component of power tool batteries that justified the outrageous prices...you know, custom made or ethereal glowing lights or little elves or something. Turns out they are just a rip off.
Fortunately for me the internals were looking familiar, a simple set of "Sub C" rechargable NiCd cells from my RC car racing days. I used to build my own racing battery packs so I couldn't help applying that here.
I had visions of using batteries that power world championship RC cars and transform my moderately powered B&D into a drill that would make screws and yet-to-be-drilled holes tremble with unspeakable fear.
When you open the battery you'll need to save some plastic bits detailed below. Don't break them.