How can I...."prepare" my ball pythons rats?

I have a half grown ball python and he currently just ate 8 (live) mice over a two day period (so I figure its time to move onto rats). He goes right after them as soon as they go into the tank. I don't want to feed him live rats as I am concerned about them hurting him. Been thinking of staring a small breeding rack and I know how to breed them, but short of sticking in a mouse trap for them to wander into I don't know how to humanly kill them and still have good food for the python. He doesn't like frozen /thawed I'm tired of wasting money on that and no I'm not going to starve him until he just eats the frozen/ thawed.