It takes roughly 50 volts to pierce your skin. AA batteries are 1 1/2 volts so..... if you put 35 to 40 of these little guys in series (end to end) you could get a little poke. I did hear of a guy killing himself with a 9volt battery by wiring a pin to each terminal and then sticking himself in each index finger. I suspect that this is a crock but ........ Essentially, batteries are safe. When touching a 9 volt to your tongue you don't really feel a shock but , if the battery is good, it will taste sour. Be careful with 9volt batteries because you can ignite your pants if you put a good battery in a pocket with some change. I've done it.