Originally Posted by Ashton
Though voltage plays a part on damage done by electrical current, it's really all about amps. Minimum for perception according to Wikipedia (because we all know how reliable it is) is 1 mA. Lethal range is 100 mA and upward.
Not sure about your numbers but you are correct. I'd imagine you could stop somebodies heart using an airsoft battery if you set it up in a manner that the current passed through the heart. THOUGH the likelyhood of anything more than a slight tingly feeling if in the water with a battery is minimal at best.
Main reason to not submerge the battery is that doing so will make the battery very useless very fast.
EDIT: just remembered an important quote I read when learning about batteries (from AAA to car batteries) "Voltage hurts but Amperage kills"