Long story short, I use the Makita 18v tool system and like a moron, I used a battery to hold something down that I was screwing into and put a drywall screw through one of the cells in the battery pack.
I bought a replacement cell and made sure it was an exact match. I pulled the old one and soldered in the new one, but no bueno. The Makita system includes a circuit board and it does smart charging things, so I think that is the issue, but it seems like a direct replacement would be a direct replacement.
