Is that why bunches of these stupid LiIon batteries won't recharge after a very long period of disuse? I know lots of my NiMH and NiCD batteries won't recharge because they've leaked or something, but that's typically obvious from either bulging cases, corrosion, or goo all over everything.
If the LiIon cells haven't burst all over the place, what exactly happens if one tries to recharge an over-discharged battery (assuming that the controller doesn't prevent it)?