Back on topic, I would have to say that it was a rare fluke! I have had more nicad powered devices that you can shake a stick at and nothing has blown up with that kind of an outcome? Actually I don't ever remember even seeing an incident with nicads that severe. I wish I knew more about batteries, the explosion is caused by the expanding gasses being held in check by the plastic wrap of the pack, then by the case itself. As kids we used to build match bombs using a similar practice, electricians tape worked the best, but I digress. What would cause a single nicad cell to go into melt down like that? Opens the door to alot of questions. I still think it's one of those rare things that happen.....similar to an event I had with a new extension cord once....but that's a topic for another thread