Batman vs Average Joe

Fight to the death 5 minute timers, the joker has implanted a bomb that will explode if neither of the heartbeats stops within 5 minutes.

No prep.

In character

Full awareness of the situation and no way to circumvent rules. Ie batman cannot knock out average joe and spend the rest of the time preforming surgery to remove and disable the bombs. Batman kills or he dies. let the battle begin.

I'm pretty sure Batman would die before he will kill.

which basically means Batman can't defeat anyone in a fight to the death...

Watch Batman: Under the Red Hood or the comics it was based on. Batman found a way out to solve a problem without killing.

Morals on, no he cant, he never ever ever ever kills.