Crisping chicken skin after braising
As some of the commenters have noted, this just might not be possible. Water is the enemy of crispy, and unfortunately for your chicken skin braising is all about moist heat. I would try searing the skin before braising, if you don't already, in order to get some of the fat rendered out and the Maillard reaction on it's way. Braise as you would, but remove the chicken five minutes before it hits doneness and place the thighs on wire rack. Put the thighs under a screaming hot broiler until, god willing, they're crispy. A torch or the searzall could also do the trick.