Even in BTAS Batman had help with things like fixing the batmobile and people making serums, etc, so I vote no for Batman to build his own weapons. I'm just not buying he can do that. He isn't Tony Stark.
Well, to be fair, the Batsuit is hardly the Iron Man suit, though. I think of Batman as being smart enough to THINK OF most of the stuff, and build some of the smaller things on his own, but with some of the more technically complicated things having to be done by Fox or whatever.