Can a li-on battery explode if you short circuit it accidentally?

I have not had one explode from accidentally short circuiting. I have had problems with the protection circuit failing after a short circuit. It is that circuit that is meant to maintain a safe operation. It limits the peak voltage of each cell during charge and prevents the cell voltage from dropping too low on discharge. Humidity, i.e. water damage etc is far more dangerous since it is the lithium that can react violently with any kind of moisture. Just like anything else, use care and common sense whenever you perform a repair. Hope this helps, good luck.In addition, the cell temperature is monitored to prevent temperature extremes.