ok, found what I was thinking of:
Originally Posted by ILLusion
Here's a better solution that I did as soon as I opened my MP7...
Chopped the battery connector end of the charger off the wall wart, soldered the leads, figured out which one was positive and which one was negative and now I just stick it in to my Systema battery charger for fuzzy logic computer controlled charging. Infinitely better than the wall-wart solution.
from this thread: