Re: Found the answer.

It's a question of how much energy a battery holds.

You can discharge a battery so fast (shorting) it can explode.

The D C and AA batteries are apparently made safe from this happening.

Make sure you don't try this with a car battery.

The wires getting warm indicate a lot of current is being drawn and/or the wires are to small to handle the amount of current being drawn.

The heat will form where the highest resistance to current is.

Savagegrace