Lithium polymer protector (LVCO)?
I found a nice collection of lithium polymer cells in a 'dead' laptop battery. Thing is, I don't want to be careful about over draining them and they don't seem to have a low voltage cut off circuit in the individual cells.
Sparkfun sells batteries with a teeny LVCO system built into the cell package like this:
What would be a reliable source of similar reliable boards that protect from over discharge?