20 Volt Max Batteries

[The white welder]

Hey y'all this is my first post here, just want to start by saying i love reading all the threads and the knowledge all of y'all have!

Now to the topic: I have a Dewalt 20 Volt drill and impact and was wondering how to make (if feasible) the Black and Decker or Porter Cable 20 volt batteries fit my Dewalt. I imagine they wont fit off the shelf, but with them all being sister companies i would think i could make them fit relatively easily. I was wondering if any of y'all have have found batteries that fit the 20 volt Dewalts or found a way to make them fit? I would like more batteries for my set but also would like to not have to pay for the Dewalt name

 

[mechanical turk]

I remember reading that there was a difference between the DeWalt batteries and the Porter Cable, Black and Decker, etc batteries that made them incompatible, maybe the temperature monitoring.

Actually found the thread, it's the shutoff mechanism being in the tool vs on the battery apparently. Here's that fairly short thread, with links to more info within:

http://www.garagejournal.com/forum/showthread.php?t=294234