I'm sure I used the right batteries. Sanyo NiCd Kr 1500-aul 1.2v 1500mah batteries. I also used a charger which was rated to charge my cells. I know I didn't damage them while soldering because I used the cold joint soldering method, which won't stick the best but will not give the cells too much heat. I'm in the process of ordering a new charger for my batteries, so I'll open the charger and watch the resistor this time, if I can feel it getting too hot, I'll try to resolder my battery using battery bars... as soon as I get my charger that is.
P.S. Anyone know where I can pick up some battery bars locally? Ordering online I would have to spend more on S&H than on battery bars.