E.I.
did he sputter and cough when he actually drank from the sippy? if so, its likely he scared himself and doesnt want that to happen again.
try a real cup. it wont be something he can do alone for a long time yet, but if he wont take a sippy, try just a regular cup and see. i had a 1 year old in my care that loved that more than a sippy (though he WOULD take a sippy.)
no matter what, wean him off the bottle. he will get the idea quickly that the bottle doesnt exist anymore, and he has to take the sippy to drink. try different kinds of sippies that might slow down the flow. we had a 2 handled cup with a soft spout that we got at target; my son and the boy i had in my care both loved those sippies. they have a plug so the flow is slower.
good luck!